June 6, 2026

Earth in a Cosmic Void? Black Holes Before Galaxies and SpaceX's Latest Triumph

Earth in a Cosmic Void? Black Holes Before Galaxies and SpaceX's Latest Triumph
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Season 29
SpaceTime Series 29 Episode 67 *Are we in a cosmic void after all? It’s an hypothesis which has been around for decades and refuses to go away: Are we in a cosmic void? *New study confirms a black hole that formed before its galaxy Astronomers using the Webb Space Telescope have identified a supermassive black hole in the early universe that formed before its host galaxy. *Another win for SpaceX over Boeing NASA has just awarded SpaceX six more crew transfer missions to the International Space Station because Boeing still can't certify its Starliner spacecraft as safe for human operation. *SkyWatch June The June Solstice, the constellation Sagittarius, and the Taurids meteor shower are among the highlights of the June night skies on Sky watch. Our Guests This Week: NASA Administrator Jared Isaacman NASA Associate Administrator Lori Glaze NASA Moon Base executive Carlos García-Galán And our regular guests: Alex Zaharov-Reutt from techadvice.life Tim Mendham from Australian Skeptics And Senior science writer and Sky and Telescope magazine contributor Jonathan Nally 🌏 Get Our Exclusive NordVPN deal here ➼ www.bitesz.com/nordvpn . The discounts and bonuses are incredible! And it’s risk-free with Nord’s 30-day money-back guarantee! ✌ If you’d like to support the podcast and gain access to bonus content by becoming a SpaceTime crew member, you can do just that through The Big Bang editions on Patreon, Spotify and Apple Podcasts. Details on the Support page on our website https://www.bitesz.com/show/spacetime/support/ For more SpaceTime and show links: https://linktr.ee/biteszHQ

The Astronomy, Space, Technology & Science News Podcast.

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This is Spacetime Series twenty nine, episode sixty seven, for

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broadcast on the fifth of June twenty twenty six. Coming

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up on Spacetime is Planet Earth in a cosmic void?

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After all?

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A new study confirms a black hole that formed before

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its galaxy and another wind for SpaceX over Boeing. All

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that and more coming up on space Time.

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Welcome to space Time with Stuart Gary.

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It's an hypothesis which has been around for decades and

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refuses to go away. Are we in a cosmic void?

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Astronomers now know that the ultimate large scale structure of

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the universe is built like a giant web, composed of

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strands of galaxies, galaxy clusters, and supers surrounding vast empty

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voids of almost nothing. The Earth, our Solar System, and

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the entire local galactic group, including the Milky Way and

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its neighboring satellite galaxies, were always thought to be on

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the edge of one of these cosmic strands, but ongoing

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readings have kept challenging that IDEA recent research reported in

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the Journal of the Monthly Notices of the Royal Astronomical

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Society has suggested that Earth main in fact be at

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the center of a two billion light ye white cosmic void.

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If so, it could explain why our local universe appears

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to be expanding faster than expected. Earth in the Milky

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Way might be drifting through a coloss or cosmic void

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spanning two billion light years. This massive region contains significantly

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less matter than the rest of the universe, thereby directly

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challenging the long helded cosmological principle that matter is distributed

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evenly throughout space. The finding suggest that our galactic home

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sits within a rare, low density pocket of the cosmos,

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making our life local neighborhood one of the largest and

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most unusual structures ever identified. And this unique positioning would

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provide a potential solution to the hubble tension that's the

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persistent disagreement between direct measurements of the universe's expansion rate.

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It could explain why our local universe appears to be

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expanding faster than expected. See if we were located in

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an underdense region, the local expansion would naturally appear faster

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to observers on Earth, potentially resolving this cosmic mystery without

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the need for any new physics or exotic energy theories

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like dark energy. In fact, the authors of the study

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now believe it's a hundred times more likely that we

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do reside in such a cosmic void compared to being

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in a region of average density, and that's a discovery

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that could fundamentally shift our perspective on the Big Banks

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after Marth Hubble constant was first proposed by Edwin Hubble

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in nineteen twenty nine to express the rate of the

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universe's expansion. It can be measured by observing the distance

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of celestial objects and how fast they're moving away from us.

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The stumbling block, however, is that extrapulating measurements of the

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distant early universe toy today using the standard cosmological model,

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predicts a slower rate of expansion than measurements of the nearby,

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more recent universe show. This is the Hubble tension. One

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of the studies authors in genal Banique from the University

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of Portsmouth says a potential solution of this inconsistency is

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that our galaxy is close to the center of a

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large cosmic void. It would cause matter to be pulled

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by gravity towards the high density exterior of the void,

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where the filaments are located. That would also lead to

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the void becoming even emptier with time. Now, as the

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void's emptying out, the velocity of objects away from us

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would be larger than if the void weren't there, and

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this would give the appearance of a faster local expansion rate.

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So a local solution like a local void would be

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a promising way to go about solving the problem. For

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the idea to stand up, Earth in our Solar system

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would need to be near the center of a void

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about a billion layers in with a density about twenty

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percent below the average density of the universe, and directly

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counting galaxies does support this theory. That's because the number

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density in our local universe is lower than in neighboring regions. However,

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the existence of such a large, deep void is controversial.

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That's because it doesn't measure specially well with the standard

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model of cosmology that suggests matter today should be far

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more uniformly spread out on such large scales. Despite this,

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the new data shows that baryon acoustic oscillations pressure waves

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generated by the Big Bang support the idea of a

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local void. These sound waves traveled for only a short

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time before becoming frozen in place. Once the universe cooled

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enough for neutral atoms to form, and they act as

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a sort of standard ruler whose angular size can be

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used to chart cosmic expansion history. A local void slightly

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distorts the relation between the bary on acoustic ostellations angular

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scale and the red shift because the velocity is induced

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by local void at its gravitational effect slightly increase the

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red shift. On top of that due to cosmic expansion.

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Redshift is the rate at which an object moves away

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from you because of the expansion of the universe. By

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considering all available barrier on acoustic oscillation measurements over the

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last twenty years, the authors showed that avoid model is

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about one hundred million times more likely than avoid free

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model with parameters designed to fit the cosmic microwave background

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radiation observations taken by the Plank satellite, so called homogeneous

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Plank cosmology. The cosmic microwave background radiation is the leftover

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energy from the Big Bang, generated when the universe cooled

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enough for the first atoms to form some trendred and

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eighty thousand years after singularity. The next step for researchers

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is to compare their local void model with other methods

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in order to estimate the history of the universe's expansion.

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This involves looking at galaxies that are no longer forming stars.

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By observing their spectra, it's possible to find what kinds

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of stars they have and in white proportion. Since more

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massive stars have shorter lives, they're absent from the older galaxies,

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thereby providing a way to establish a galaxy's age. Astronomers

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can then combine this age with the galaxy's redshift, how

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much the wavelength of light has been stretched, to tell

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us how much the universe has expanded while light from

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the galaxy was traveling towards us, and this will shed

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new light on the universe's expansion history. This is space

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time still to come. A new study confirms a black

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hole that formed before its galaxy, and another wind for

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SpaceX overbowing all that and more still to come on

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space time. Astronomers using the Web Space telescope have identified

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a super massive black hole in the early universe that

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must have formed before its host galaxy. For years, scientists

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have been debating the question of which comes first, the

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galaxy or its central black hole, and the truth is

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we don't really know for sure, but scientists have long

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thought it could be much easier for the galaxy to

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form first, with large stars within the galaxy consuming their

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fuel and collapsing, the form black holes, which can then

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gobble up surrounding material and merge with other black holes

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over time to form more.

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And more massive entities.

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But it's been hard to figure out how black holes

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millions to billions of times the mass of our Sun,

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thousands of which have now been detected in the early universe,

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could have grown so quickly from such small seeds. Now

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are reporting the journal Nature and in the Monthly Notices

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of the Royal Astronomical Society claims the new web observations

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have detected clear evidence that at least some super massive

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black holes were enormous from their very beginning, forming without

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a stellar collapse phase and without a significantly more massive

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host galaxy to feed them.

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One of the studies the authors, ROBERTA.

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Meelino from Cambridge University, says it's a paradigm shift, a

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turtle revisit of the classical scenarios of how black holes

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form and grow. The author's conclusions are based on detailed

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observations of Able twenty seven forty four QSO one, a

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pretatypical little red dot that existed just seven hundred million

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years after the Big Bang. Although ABLE twenty seven forty

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four QSO one is only thirteen hundred light years wide

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and its lightest been traveling for some thirteen point one

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billion years, it's easier to study the most other little

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red dots because it's been gravitationally lensed by galxy cluster.

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Able twenty seven forty four also earnest Pandora's cluster, so

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it's both magnified and triply imaged, appearing in three different

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locations across the sky. Initial studies revealed compilling evidence that

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it may be little more than a cloud of glowing

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hydrogen and helium gas circling a super massive black hole

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estimated at some forty million times the mass of our Sun.

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But as with other early black holes, the scis covered

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by web there was uncertainty about whether it really was

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that massive. See before now, all the mass measurements of

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black holes in the early universe have been indirect based

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on assumptions of what we know about super massive black

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holes in the local universe, and we didn't really know

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if these assumptions also applied to the distant universe. So

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the authors recognize that if this black hole is as

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massive as it looks, they should be able to use

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the integral field unit on webs needing for its spectrograph

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to trace the effects of its gravity on the gas

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swelling around it, while also mapping the distribution of various

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elements in the gas. So the authors use these observations

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to map motions of hydrogen gas around the black hole.

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When they plotted the rotation velocity as a function of

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distance from the center, they found that the gas has

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capellarian motion, in other words, at orbits a central point,

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in the same way as the planet's or but our

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sun in our Solar system. That's important because it tells

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the authors that most of the mass in the super

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massive black hole is concentrated at the center. If the

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mass were more distributed, as it would be if there

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were lots of nearby stars, the gas would not have

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this perfect Keplarian rotation. Since keplari immersion is governed by

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the simple laws of gravity, the authors were able to

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use this gas velocity measurement to calculate the black hole's

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mass directly, a feat that had not previously been possible.

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They found that not only was the super massive black

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hole immense roughly fifty million solar masses in size, It

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makes up, at a minimum at astonishing two thirds of

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the system's total mass, and this proportion is thousands of

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times greater than in nearby galaxies, where super massive black

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holes make up only a tiny fraction of a host

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galaxy's total mass. The where observation supported these results, showing

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that the gas throughout ABLE twenty seven forty four qso

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one is almost entirely hydrogen and helium, with very little

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of the heavier elements like oxygen that would be expected

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in a galaxy rich in stars and stellar debris with

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a metallicity less than zero point five percent that of

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the Sun. Able twenty seven forty four qso one is

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also one of the most pristine galactic environments ever measured.

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It's the first direct measurement of a black hole mass

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within the first billion years after the Big Bang, and

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it's consistent with previous measurements. The outsized mass of ABLE

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twenty seven forty four qso one relative to its host

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galaxy suggests that it could not have formed gradually from

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much smaller stellar mass black holes merging together, So it

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seems the authors have found a black hole that does

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not have a substantial host galaxy and that has pre

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dated stellar processes. This is evidence of primordial black holes

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or direct collapse black holes, which have been theorized but

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until now not confirmed whether able twenty seven forty four

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qso once black hole evolved from a heavy sea that

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formed within the first seconds of the Big Bang, or

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somewhat later from the collapse of a giant cloud of gas.

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It was almost certainly born big and may still be

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in the early stages of building up a galaxy around it.

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This is space time still to come. Another win for

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SpaceX over Boeing and the June solstice. The constellation Sagittarius

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and the towards Medial shower are among the highlights of

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the June night skies on SkyWatch. NASA's just awarded SpaceX

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six more crew transfer missions to the International Space Station

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because Boeing still can't certify it Styleliner spacecraft as safe

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for human operation. Ongoing problems with Starliner has seen Boeing

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spend a decade and billions of dollars on the spacecraft,

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which couldn't even safely return its own astronauts back to

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Worth on its first man mission. When Boeing did finally

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fly its first and so far only man flight aboard

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the CST one hundred Styliner to the space station, problems

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with a vehicles proportion system and persistent healing leaks forced

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NASA to abandon plans to use the same vehicle to

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return the crew back to Earth. Instead, they will have

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stranded on the space station for nine months until rival

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company SpaceX were able to set a Dragon spacecraft there

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on a rescue mission. Unlike Boeing, SpaceX has been reliably

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transporting people to and from the orbiting up post since

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twenty twenty. It's now successfully launched nineteen man missions using Dragon,

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including thirteen for NASA and six for private companies. Even

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more embarrassing for Boeing, NASA gave them four point two

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billion dollars to develop Stylner, they only gave SpaceX around

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half that amount two point six billion, to develop its

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crew Dragon. Of course, Dragon first began flying for NASA

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on cargo emissions to the space station years earlier, but

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SpaceX always intended Dragon to eventually carry people. Now, making

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the scene even more interesting is a third player, Sera

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space which has been quietly developing its dream Chaser lifting

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buddy spaceplane design. Although originally developed as a manned space

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transport vehicle for journeys to and from the space station,

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dream Chaser is now being evolved into a third cargo

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and resupply ship as part of NASA's commercial resupply Services

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to program for space station operations that zero space insists.

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Future man missions for dream Chaser are further down the line.

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As it is, dream Chaser will join SpaceX's Cargo Dragon

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and Orbital Sciences Signus cargo ships in the space station

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supply role. The first of the dream Chaser space plane's Tenacity,

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has already completed a series of milestones, including electromagnetic interference testing,

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high speed ground tow tests, recovery rehearsals, following landing, communications

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testing with mission control using NASA tracking and data relay systems,

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and acoustic testing at the Kennedy Space Center. Tenacity is

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now back at Sierra Space's Louisville, Colorado factory for flight

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software qualification and final thermal protection system closeouts. It will

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then move into final mission specific paylert integration target completion

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by December. Its maiden test flight won't be to the

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space station, just to Loweth orbit, it'll undertake its orbital

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test four NASA aboard a United Launch Alliance Vulcan Centaur

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rocket from the Cape Canaveral Space Force Space in Florida.

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Once in orbit, it'll be taken through a series of

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control and inflight maneuvers it tests its orbital reaction systems

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and atmosphere re entry capabilities, ultimately gliding to a controlled

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landing on the former Space Shuttle runway at the Kennedy

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Space Center.

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This is space.

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Time, Okay, time that out to turn our eves to

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the skies as we check out the celestious sphere for

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the month of June on SkyWatch. June is the fourth

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month of the year in the Old Roman calendar. It's

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named after Juno, who was the wife of Jupiter and

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is also the equivalent of the Greek goddess Hera.

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Another belief is that the.

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Month's name comes from the Latin word Junorees, which means

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the younger ones. June also marks the windness solstice in

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the Southern Hemisphere, and of course it means the arrival

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of summer for our lucky listeners north of the equator.

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It will happen at six twenty four in the evening

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of Sunday June the twenty first Australian Eastern Standard time.

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That's four twenty four in the morning Sunday June twenty first,

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US Eastern daylight time and eight twenty four in the

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morning Greenwich meantime. The June solstice occurs when the Sun

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reaches its most northerly point in the sky is seen

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from Earth Zenith, appearing to be directly over the Tropic

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of Cancer. It all happens because the seasons are governed

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by the tilt of Earth's axis as it journeys around

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the Sun. Every year, on the day of the June solstice,

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the earth south pole is tilted by twenty three and

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a half degrees away from the Sun, so the Sun

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rises north of east and sets north of west. When

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the south pole is tilted towards the Sun, it's the

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southern hemispheres summer. Between these two we have the autumn

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and spring Equinox. Variations in temperatures on Earth aren't determined

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by the Earth's orbital distance from the Sun, but rather

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the angle of the Sun's ray striking the Earth. In

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the summer, the suns high in the sky and the

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rays hit the Earth at a steep angle, but in winter,

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the sun's lower down in the sky and the rays

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strike the Earth at a more shallow angle. In most

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parts of the world, seasons begin on the day of

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the equinox and solstice. However, in Australia, seasons begin on

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the first day of a specific calendar month March for autumn,

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June for winter, September for spring, and December for summer. Okay,

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let's turn to the constellations, and almost directly overhead this

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time of the year, we have the spectacular constellation Virgo.

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The constellation Virgo is named after Virgo, the goddess of

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justice and the harvest in ancient Greek mythology, who used

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his scales to weigh good and evil. However, she became

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so disenchanted with the dear of evil men she threw

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away his scales and retreated to the heavens. They're Interestingly,

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the ancient Egyptians also associate Virgo with agriculture. There she

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was the goddess Isis, who sprinkled heads of wheat across

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the sky.

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Forming the Milky Way.

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To science, Virgos a tightly packed region at space containing

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some two thousand galaxies, all gravitationally bound into a giant

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galaxy cluster located some sixty million light years away.

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Now our own.

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Local group of galaxies, which is primarily bound by the

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Milky Way, and Andromeda are an outlying member of this cluster. Now,

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the Virgo cluster is the heart of the Virgo Supercluster,

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one of the largest known structures in the universe, a

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massive galactic node in the large scale, cosmic web like structure.

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Of the universe.

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The mass of the Virgo supercluster is so great that

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its gravity generates the Virgo centric flow, causing our Milky

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Way galaxies, all as Andromeda, and all the other members

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of the local group to move towards the supercluster at

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about four hundred kilometres per second. That's despite the accelerated

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expansion of the universe over cosmic timescales. The Virgo Supercluster

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is now thought, in turn, to be simply a lobe

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of an even bigger galaxy supercluster called Laniakia, the center

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of which is known as the Great Attractor. Despite the

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Virgo cluster size, it's so far away it's hard to

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see without a decently sized backyard telescope. You'll need something

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at least one hundred millimeters in diameter or larger. Directly

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overhead right now is the constellation Corvus.

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The crow.

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Greek mythology tells us that Corvus could talk to humans,

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that he was a lazy bird, and so Apollo took

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away his ability to speak and banished into the heavens.

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One of the highlights and the constellations Virgo and Corvus

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is the spectacular Sombrero galaxy M one o four. Visible

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with a good pair of binoculars or a small telescope,

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there stunning spiral galaxy you've seen almost their john, providing

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audiences with a spectacular back lit view of its galactic

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bold stars and the molecular gas and dust lanes in

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its arms. M one zero four is located some thirty

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one million light years away, and it's moving away from

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our Milky Way galaxy at about one thousand kilometas per second.

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A light year is ten trillion kilometers the distance of

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photon can travel in a year at the speed of light,

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which is about three hundred thousand kilometas per second in

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a vacuum and the ultimate speed limit of the universe.

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The Sombrero galaxy has a diameter of about fifty thousand

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light years, about thirty percent the size of our Milky Way.

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It's surrounded by around two thousand globular clusters and has

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an active central super massive black hole at least a

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billion times the mass of the Sun.

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Now.

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By comparison, the Sagittarius, a star that's the super massive

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black hole at the center of our Milky Way galaxy,

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is just four point.

359
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Three million times the mass of the Sun.

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The globular clusters are tight stellar balls comprising millions to billions

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of stars which were either the central remnants of a

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smaller galaxy cannibalized by a larger one, or they were

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originally all part of the same stellar nursery, formed at

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the same time in the same collapsing molecular gas in

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dust cloud. The brightest star in the constellation Virgo is Spiker,

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a spectroscopic binary located some two hundred and fifty light

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years away. Spectroscopic binaries are pairs of stars so close

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to each other that they could only be separated using

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a spectrograph to determine the individual chemical makeup of each component.

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Looking about twenty degrees above the western horizon in the

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early evening this time of the year, you'll find the

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brightest star in the night sky, the Dog Star. Serious

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only the Sun, the moon, and the planet Venus looked brighter.

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To the northwest or right of Sirius from the southern

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hemisphere is another fairly bright star called Procion, the brightest

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star in Canis minor, the lesser dog. In Greek mythology,

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Canis Major and Canis Minor were Orion's two hunting dogs.

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Prosion is another binary star system, this one comprising a

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spectral type F main sequence white yellow star Proceeon A,

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and a faint white dwarf companion Proteon B. Main Sequence

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stars are those undergoing core hydrogen fusion to helium. Astronomers

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00:22:18.000 --> 00:22:21.720
describe stars in terms of spectual types, a classification system

383
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based on temperature and characteristics. The hottest, the most massive,

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most luminous stars in the sky are known as special

385
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type O blue stars. They're followed by spectro type B

386
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blue white stars, then spectual type A white stars, spectral

387
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type F white yellowish stars, followed by spectrotype G yellow

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stars that's where our sun fits in, then spectrotype K

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irene stars, and the coolest and least massive stars known

390
00:22:47.799 --> 00:22:52.319
are spectual type M red dwarf stars. Each specual classification

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00:22:52.440 --> 00:22:56.359
can further be subdivided using a numerical digit to represent temperature,

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with zero being the hottest denying the coolest, and then

393
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you can out a Roman numeral to represent luminosity. Now

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put that all together, and our own local star as Sun,

395
00:23:06.359 --> 00:23:09.720
becomes a G two V or G two five yellow

396
00:23:09.799 --> 00:23:14.039
dwarf star. Also included in the stellar classification system are

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spectrotypes LT and Y, which are assigned to failed stars

398
00:23:17.839 --> 00:23:20.519
known as brown dwarves, some of which were born as

399
00:23:20.559 --> 00:23:23.839
spectual type M red dwarf stars but became brown dwarfs

400
00:23:23.920 --> 00:23:27.400
after burning off some of their mass. Brown dwarves fit

401
00:23:27.440 --> 00:23:30.319
into a category between the largest planets, which are around

402
00:23:30.319 --> 00:23:33.359
thirteen times the mass of Jupiter, and the smaller spectual

403
00:23:33.440 --> 00:23:36.440
type M red dwarf stars, which are between seventy five

404
00:23:36.480 --> 00:23:39.480
and eighty times the mass of Jupiter or zero point

405
00:23:39.599 --> 00:23:44.039
zero eight solar masses. White dwarves are the stellar corpses

406
00:23:44.079 --> 00:23:47.759
of Sun like stars, having used up their nuclear fuel

407
00:23:47.799 --> 00:23:51.319
supply fusing hydrogen into helium in their core. These stars

408
00:23:51.359 --> 00:23:55.079
expand into red giants as they begin fusing helium into

409
00:23:55.119 --> 00:23:59.319
carbon and oxygen. However, some like stars aren't massive enough

410
00:23:59.359 --> 00:24:02.759
to fuse carbon and oxygen into heavier elements, and so

411
00:24:02.880 --> 00:24:06.880
they turn off. They're outer gaseous envelopes then float off

412
00:24:06.880 --> 00:24:11.519
into space as spectacular objects known as planetary nebulae. What's

413
00:24:11.640 --> 00:24:15.039
left behind is a super dense, white outstellar core about

414
00:24:15.039 --> 00:24:18.079
the size of the Earth, a white dwarf, which will

415
00:24:18.079 --> 00:24:22.480
slowly cool over the eons. The white dwarf, Procion B

416
00:24:22.799 --> 00:24:24.880
is about zero point six times the mass of the

417
00:24:24.920 --> 00:24:28.799
Sun and has a diameter of around eighty six hundred kilometers.

418
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Located some eleven point six light years away. Prosion A

419
00:24:32.880 --> 00:24:34.759
has about one and a half times the mass and

420
00:24:34.799 --> 00:24:38.799
twice the radius of our Sun. Interestingly, Prosion A has

421
00:24:38.839 --> 00:24:42.440
about seven times the Sun's luminosity. It makes it unusually

422
00:24:42.480 --> 00:24:45.240
bright for this type of star, and that suggests that

423
00:24:45.279 --> 00:24:48.039
it's starting to evolve off the main sequence. After having

424
00:24:48.160 --> 00:24:51.799
fused nearly all of its care hydrogen into helium. It's

425
00:24:51.880 --> 00:24:55.359
expanding out to become a subgiant as it begins fusing

426
00:24:55.440 --> 00:24:59.200
core helium into oxygen and carbon, and burning hydrogen into

427
00:24:59.240 --> 00:25:01.960
helium in the sh shell around the core. As it

428
00:25:02.000 --> 00:25:06.079
continues to expand. The star will eventually swell somewhere between

429
00:25:06.119 --> 00:25:08.640
eighty and one hundred and fifty times its current diameter,

430
00:25:08.920 --> 00:25:13.039
becoming a bloated red or orange giant. That'll probably happen

431
00:25:13.079 --> 00:25:16.119
within the next ten to one hundred million years. The

432
00:25:16.160 --> 00:25:18.960
two stars press on A and B all but each

433
00:25:18.960 --> 00:25:21.680
other every forty point eight to earth years, at an

434
00:25:21.680 --> 00:25:25.799
average distance of fifteen astronomical units. That's about the distance

435
00:25:25.839 --> 00:25:29.680
of Mercury's orbit around the Sun. An astronomical unit is

436
00:25:29.680 --> 00:25:32.279
the average distance between the Earth and the Sun, about

437
00:25:32.279 --> 00:25:35.319
one hundred and fifty million kilometers or eight point three

438
00:25:35.400 --> 00:25:38.880
light minutes. Looking to the north northwest from the southern

439
00:25:38.920 --> 00:25:41.680
hemisphere this time of year, and you'll see the constellation

440
00:25:41.880 --> 00:25:44.440
Leo the Lion, looking more like a bunch of stars

441
00:25:44.480 --> 00:25:48.119
shaped like an upside down question mark, located thirty six

442
00:25:48.160 --> 00:25:51.200
point seven light years away. A Tourists is a bloated,

443
00:25:51.279 --> 00:25:54.839
aging red giant about seven point one billion years old

444
00:25:54.960 --> 00:25:58.200
and nearing the end of its life. Having used up

445
00:25:58.200 --> 00:26:01.480
all its core hydrogen, it's now using helium into carbon

446
00:26:01.559 --> 00:26:04.920
and oxygen. This has caused the start, which is only

447
00:26:04.960 --> 00:26:07.480
slightly more massive than our Sun, to expand out to

448
00:26:07.519 --> 00:26:10.759
around twenty five times the Sun's diameter, becoming about one

449
00:26:10.839 --> 00:26:12.680
hundred and seventy times as luminous.

450
00:26:13.319 --> 00:26:14.440
It'll soon puff.

451
00:26:14.240 --> 00:26:17.759
Off its outer gaseous envelope as a planetary nebulae, exposing

452
00:26:17.839 --> 00:26:21.119
its white hot stellar core and becoming a white dwarf.

453
00:26:21.839 --> 00:26:25.119
In Greek mythology, Acturus was the guardian of the bear.

454
00:26:25.920 --> 00:26:27.680
This is a reference to it being next to the

455
00:26:27.720 --> 00:26:31.599
constellations Ursa Major and Ursa Minor, the greater and lesser bears.

456
00:26:32.359 --> 00:26:36.279
There's some indications that Arcturus could have a binary stellar companion,

457
00:26:36.359 --> 00:26:39.599
but the results are inconclusive at the stage. There's also

458
00:26:39.680 --> 00:26:43.119
speculation that it could have a large planet or substellar

459
00:26:43.160 --> 00:26:46.279
object about twelve Jupiter masses orbiting it. Now that's close

460
00:26:46.319 --> 00:26:49.920
to brown dwarf size, but again the research remains inconclusive.

461
00:26:50.559 --> 00:26:52.839
To the east, when viewing from the southern hemisphere this

462
00:26:52.920 --> 00:26:55.319
time of year, are the three bright stars and the

463
00:26:55.359 --> 00:26:59.960
constellation Libra, the scales of Justice. They're visible about halfway

464
00:27:00.000 --> 00:27:03.200
They are about forty degrees above the horizon. Now, these

465
00:27:03.240 --> 00:27:06.559
also represent the claws of Scorpius, the scorpion which is

466
00:27:06.640 --> 00:27:10.200
chasing a rin across the sky. The brightest star in

467
00:27:10.240 --> 00:27:15.000
the constellation Scorpius is Alpha Scorpii, or Antaries, the scorpion's

468
00:27:15.039 --> 00:27:18.880
heart easily seen with the unaided eye. The red super

469
00:27:18.920 --> 00:27:22.400
giant Antares is located some five hundred and fifty light

470
00:27:22.480 --> 00:27:25.440
years away, and it's one of the largest known stars

471
00:27:25.480 --> 00:27:28.880
in the universe. It has about eighteen times the mass,

472
00:27:29.000 --> 00:27:31.480
about eight hundred and eighty three times the diameter of

473
00:27:31.519 --> 00:27:35.400
our sun, and Tara's is also around ten thousand times

474
00:27:35.519 --> 00:27:38.920
more luminous than our Sun. Now looking to the southeast

475
00:27:38.920 --> 00:27:42.359
from the southern hemisphere and you'll see the constellation Sagittarius.

476
00:27:42.400 --> 00:27:42.920
The archer.

477
00:27:43.640 --> 00:27:46.960
Sagittarius is important because it marks the direction towards the

478
00:27:47.000 --> 00:27:50.200
center of our Milky Way galaxy. In fact, located just

479
00:27:50.240 --> 00:27:53.720
twenty seven thousand light years away in the direction of Sagittarius,

480
00:27:53.799 --> 00:27:56.880
is the home of the galaxy's central super massive black hole.

481
00:27:57.079 --> 00:28:01.960
Sagittarius a star to the engine Babylonians, Sagetarius was the

482
00:28:02.000 --> 00:28:05.839
god Nrgle the Centaur, a creature half man and half horse.

483
00:28:06.440 --> 00:28:09.839
By the time Greek mythology took over, Sagittarius was also

484
00:28:09.920 --> 00:28:14.079
carrying a bow loaded with an arrow, pouring directly towards Antares.

485
00:28:14.319 --> 00:28:17.559
At the heart of Scorpius, the scorpion, the center of

486
00:28:17.559 --> 00:28:20.559
the Milky Way, and its supermassive black hole. Sagittarius, a

487
00:28:20.680 --> 00:28:25.880
star lie in the westernmost part of Sagittarius. Sagittarius has

488
00:28:25.960 --> 00:28:30.559
many spectacular highlights. Alpha Sagittaria or rook Bat meaning the

489
00:28:30.680 --> 00:28:34.559
Archer's Knee, is a special type beat blue star located

490
00:28:34.559 --> 00:28:36.759
some one hundred and eighty two light years away. It

491
00:28:36.839 --> 00:28:38.480
is two and a half times that I am of

492
00:28:38.519 --> 00:28:42.599
the Sun and is about forty times as luminous. Astronomers think.

493
00:28:42.640 --> 00:28:45.000
It's surrounded by a dense debris disk and as a

494
00:28:45.039 --> 00:28:48.200
newborn companion star which is only just starting to join

495
00:28:48.240 --> 00:28:52.279
the main sequence. The brightest star in Sagittarius is Epsilon

496
00:28:52.400 --> 00:28:57.240
Sagittary or Calcistrallas, the southern part of the bow. Epsilon

497
00:28:57.319 --> 00:29:00.359
Sagittari is a binary system located some one undred and

498
00:29:00.359 --> 00:29:03.839
forty three light years from Earth. The primary star is

499
00:29:03.880 --> 00:29:06.839
an evolved spectual type B blue giant nearing the end

500
00:29:06.839 --> 00:29:09.759
of its life on the main sequence. It has about

501
00:29:09.759 --> 00:29:11.640
three and a half times the mass of the Sun,

502
00:29:11.799 --> 00:29:15.400
almost seven times the Sun's radius, and he's radiating around

503
00:29:15.400 --> 00:29:19.240
three hundred and sixty three times the Sun's luminosity. It's

504
00:29:19.279 --> 00:29:22.559
also a strong X ray source, and he's spinning very rapidly,

505
00:29:22.599 --> 00:29:25.359
with an estimated radio velocity of some two hundred and

506
00:29:25.440 --> 00:29:29.359
thirty six kilmetus per second. The system also displays an

507
00:29:29.359 --> 00:29:33.160
excess of infrared radiation emissions, suggesting the presence of a

508
00:29:33.160 --> 00:29:36.880
circumstellar disc of dust. The second star in the system

509
00:29:37.000 --> 00:29:41.039
appears to be inside this debris disc. Astronomers think it's

510
00:29:41.039 --> 00:29:43.519
going to be a spectrotype G yellow dwarf star with

511
00:29:43.559 --> 00:29:46.799
about ninety five percent the mass of the Sun. Sigma

512
00:29:46.799 --> 00:29:51.039
Sagittari or Nunkey, is the constellation's second brighter star. The

513
00:29:51.119 --> 00:29:54.759
name Nunkey's Babylonian. However, its meaning has been lost through

514
00:29:54.839 --> 00:29:58.079
the sunds of time. It's thought to represent the ancient

515
00:29:58.119 --> 00:30:01.559
Babylonian sacred city of Urd two on the Euphrates River.

516
00:30:02.240 --> 00:30:05.119
Now if correct, they would make Donkey the oldest stellar

517
00:30:05.200 --> 00:30:09.359
name currently in use. It's another spectrotype B blue star

518
00:30:09.599 --> 00:30:12.799
located's some two hundred and sixty light years away. It

519
00:30:12.799 --> 00:30:15.440
has about eight times the Sun's mass, about four and

520
00:30:15.480 --> 00:30:18.319
a half times it's radius, and some three thousand, three

521
00:30:18.400 --> 00:30:22.759
hundred times the Sun's luminosity. Zetas Sagittaria, or a cellar

522
00:30:22.880 --> 00:30:26.119
the Armpit is a binary star system located some eighty

523
00:30:26.119 --> 00:30:29.079
eight light years away, and it's currently speeding away from

524
00:30:29.119 --> 00:30:32.480
our Solar system. Astronomers think that it may have been

525
00:30:32.519 --> 00:30:34.319
as near as one and a half light years from

526
00:30:34.319 --> 00:30:36.960
the Sun around one point four million years ago. That

527
00:30:37.000 --> 00:30:40.680
would have made it an extremely close former neighbor. One

528
00:30:40.680 --> 00:30:43.000
of the stars in the system is a spectrotype a

529
00:30:43.200 --> 00:30:47.039
white giant, while the other is a spectrotype a white supergiant.

530
00:30:47.279 --> 00:30:50.119
The pair orbiting each other every twenty one earth years.

531
00:30:50.680 --> 00:30:53.839
The system's combined mass is about five point two six

532
00:30:53.960 --> 00:30:57.519
times the mass of the Sun. Delta Sagittaria or cals

533
00:30:57.599 --> 00:31:01.200
Meridianalys appears to be a double star system located three

534
00:31:01.240 --> 00:31:03.720
hundred and forty eight light years away and listed as

535
00:31:03.759 --> 00:31:08.440
an orange giant. Then there's Ether Sagittary, another double star system.

536
00:31:08.519 --> 00:31:10.799
It's one located one hundred and forty six light years

537
00:31:10.799 --> 00:31:14.279
from Earth. The primary star is an aging, bloated red

538
00:31:14.319 --> 00:31:17.680
giant on the asyntopic giant branch. That means it's no

539
00:31:17.759 --> 00:31:20.599
longer fusing hydrogen or helium in its core and as

540
00:31:20.680 --> 00:31:24.440
instead fusing heavier elements in the core and burning hydrogen

541
00:31:24.480 --> 00:31:28.000
and helium in its shell. It's already expanded out to

542
00:31:28.039 --> 00:31:30.319
some fifty seven times the radius of the Sun and

543
00:31:30.440 --> 00:31:33.440
is now nearing the end of its life. The second

544
00:31:33.440 --> 00:31:36.680
star in the system is a spectrotype F main sequence

545
00:31:36.759 --> 00:31:39.519
white yellow dwarf, which appears to be in a binary

546
00:31:39.559 --> 00:31:42.799
system with a primary star orbiting it every one two

547
00:31:42.839 --> 00:31:47.000
hundred and seventy earth years. PI Sagittary or Albalder is

548
00:31:47.039 --> 00:31:50.079
a triple star system located around five hundred and ten

549
00:31:50.160 --> 00:31:53.480
light years away. The primary star appears to be another

550
00:31:53.559 --> 00:31:56.880
spectrotype F white yellow giant, and it looks like it's

551
00:31:56.960 --> 00:32:00.000
just about exhausted its core hydrogen and he's now moved

552
00:32:00.200 --> 00:32:03.279
off the main sequence and evolving into a red giant.

553
00:32:03.799 --> 00:32:06.960
PI Sagittary has two nearby companions, but we know little

554
00:32:06.960 --> 00:32:10.799
about them. Beta Sagittary, or our Cab the Achilles tendon,

555
00:32:11.039 --> 00:32:14.400
is a designation shared by two separate star systems, one

556
00:32:14.440 --> 00:32:16.839
around three hundred and seventy eight light years from Earth,

557
00:32:16.960 --> 00:32:19.279
the other on three hundred and seventy nine light years away.

558
00:32:19.720 --> 00:32:23.319
Beta Sagittary A is a spectrotype B blue dwarf star

559
00:32:23.599 --> 00:32:27.319
or Beta Sagittary B, is a white yellow giant lying

560
00:32:27.359 --> 00:32:30.119
in the very center of the constellation is Nervous Sagittary,

561
00:32:30.240 --> 00:32:32.960
which was only discovered in twenty fifteen, and as the

562
00:32:33.079 --> 00:32:36.039
name suggests, is a nerva, a white dwarf in a

563
00:32:36.079 --> 00:32:39.519
binary system which is constantly drawing material off a close

564
00:32:39.640 --> 00:32:43.640
orbiting companion star. Once enough mass reaches the surface of

565
00:32:43.680 --> 00:32:46.480
the white dwarf, the added mass will undergo a thermo

566
00:32:46.640 --> 00:32:50.359
nuclear explosion, causing the star to briefly light up like

567
00:32:50.400 --> 00:32:53.519
a beacon and then slowly fade again over the following

568
00:32:53.559 --> 00:32:54.599
few weeks or months.

569
00:32:55.200 --> 00:32:56.519
The blast isn't enough.

570
00:32:56.319 --> 00:32:59.119
To destroy the white dwarf, only the additional material it's

571
00:32:59.160 --> 00:32:59.720
picked up.

572
00:33:00.240 --> 00:33:00.400
Now.

573
00:33:00.440 --> 00:33:02.960
Once the star's gone other and the additional mass has

574
00:33:03.000 --> 00:33:06.039
been burnt off, the same cycle starts over again, and

575
00:33:06.079 --> 00:33:09.359
the process repeats itself and time scars ranging from every

576
00:33:09.440 --> 00:33:13.559
few years to tens of thousands of years. The Sagittarius

577
00:33:13.640 --> 00:33:17.720
constellation also hosts many star clusters and nebulae, including some

578
00:33:17.759 --> 00:33:21.160
of the best known astronomical objects in the sky. These

579
00:33:21.200 --> 00:33:25.240
include the spectacular lagoon Nebula Messier eight, a stunning pink

580
00:33:25.240 --> 00:33:28.640
emission Nebula that's located five thousand light years away and

581
00:33:28.720 --> 00:33:31.440
measures one hundred and forty light years by sixty light

582
00:33:31.519 --> 00:33:35.119
years across. The central area of the Lagoon nebula is

583
00:33:35.200 --> 00:33:38.480
also known as the hourglass nebula. That's because of its

584
00:33:38.480 --> 00:33:41.599
distinctive shape because of matter propelled by a massive star

585
00:33:41.720 --> 00:33:45.119
forming region called Herschel thirty six. It's one of the

586
00:33:45.160 --> 00:33:48.880
few star forming nebulae possible to see with the unaided eye.

587
00:33:49.400 --> 00:33:53.039
The Lagoon nebula was instrumental in the discovery of Boch globules,

588
00:33:53.160 --> 00:33:55.799
more than seventeen thousand of which have now been found

589
00:33:55.839 --> 00:34:00.000
in the nebula. Astronomers believe these globules contain embryonic press

590
00:34:00.000 --> 00:34:05.039
phido stars destined to eventually become new stellar generations. Probably

591
00:34:05.079 --> 00:34:08.880
the most famous nebula in Sagittarius is messi As seventeen,

592
00:34:09.159 --> 00:34:13.079
better known as the Horsehaed nebula. It's located some eight

593
00:34:13.119 --> 00:34:15.880
hundred ninety light years away in a dense region of

594
00:34:15.960 --> 00:34:20.719
ironized atomic hydrogen, also known as the Amiga or Swan nebula.

595
00:34:20.800 --> 00:34:23.679
It spans some fifteen light years in diameter and as

596
00:34:23.719 --> 00:34:26.639
some eight hundred times the mass of our Sun. It's

597
00:34:26.719 --> 00:34:29.400
considered one of the brightest and most massive star forming

598
00:34:29.440 --> 00:34:32.079
regions in our galaxy, with a geometry similar to the

599
00:34:32.119 --> 00:34:35.039
Iryon nebula, except that we're seeing it edge on rather

600
00:34:35.079 --> 00:34:39.239
than face on. The open star cluster NGC sixty six

601
00:34:39.360 --> 00:34:43.519
eighteen lies embedded in the nebulosity and causes gases from

602
00:34:43.559 --> 00:34:46.840
the nebula to shine due to intense radiation from all

603
00:34:46.840 --> 00:34:50.920
the hot yang stars. Open star clusters are loosely bound

604
00:34:50.920 --> 00:34:53.679
groups of a few thousand stars which were originally all

605
00:34:53.719 --> 00:34:56.719
formed in the same molecular gas and dust cloud, but

606
00:34:56.800 --> 00:34:59.960
they're not as densely bound gravitationally.

607
00:34:59.159 --> 00:35:00.400
As globular cloud lusters.

608
00:35:01.119 --> 00:35:04.360
Open clusters generally survive for a few hundred million years,

609
00:35:04.400 --> 00:35:07.320
with the most massive ones surviving for maybe a few billion.

610
00:35:08.039 --> 00:35:11.519
In contrast, the more massive globular clusters exert so much

611
00:35:11.559 --> 00:35:14.920
stronger gravitational attraction on their members that they can survive

612
00:35:15.039 --> 00:35:18.960
for much longer billions and billions of years. The nebula's

613
00:35:19.000 --> 00:35:22.280
thought to contain around eight hundred stars, including over one

614
00:35:22.320 --> 00:35:25.519
hundred of the largest most massive spectrotype O and B

615
00:35:25.519 --> 00:35:29.559
blue stars. More than one thousand additional stars are also

616
00:35:29.639 --> 00:35:33.000
being formed in the surrounding molecular gas and dust clouds,

617
00:35:33.599 --> 00:35:35.840
and with an age of just a million years, it's

618
00:35:35.880 --> 00:35:38.519
also one of the youngest clusters known in the galaxy.

619
00:35:39.119 --> 00:35:42.400
The cloud of interstellar material which formed the nebula is

620
00:35:42.480 --> 00:35:46.280
roughly forty light years across and contains some thirty thousand

621
00:35:46.400 --> 00:35:51.239
solar masses. Another spectacular site worth searching for in Sagittarius

622
00:35:51.360 --> 00:35:55.239
is the Trifford nebula Messi twenty. It's another large star

623
00:35:55.360 --> 00:35:58.679
forming a mission nebula containing many very young hot stars.

624
00:35:59.320 --> 00:36:02.400
Located between two thousand and nine thousand light years away.

625
00:36:02.480 --> 00:36:06.039
The Triffid nebula has a diameter of approximately fifty light years.

626
00:36:06.599 --> 00:36:09.760
The outside of the Triffid is a bluish reflection nebula,

627
00:36:09.840 --> 00:36:13.320
while the inner region is glowing pink thanks to ionized hydrogen.

628
00:36:13.840 --> 00:36:17.079
There are two dark bands dividing the Triffid nebula into

629
00:36:17.079 --> 00:36:21.440
three regions or lobes. Hydrogen in the nebula's ionized by

630
00:36:21.480 --> 00:36:24.719
a central triple star, which formed in the intersection between

631
00:36:24.760 --> 00:36:29.079
the two dark bands, creating its characteristic pink color. Another

632
00:36:29.159 --> 00:36:32.719
star forming region NGC six double five nine, located some

633
00:36:32.840 --> 00:36:36.199
five thousand light years away, contains both red emission and

634
00:36:36.239 --> 00:36:40.400
blue reflection regions. The grouping of the Lago nebula, the

635
00:36:40.440 --> 00:36:44.039
Triffid nebula, and NGC six double five nine are known

636
00:36:44.119 --> 00:36:47.800
as the Sagittarius triple and are a spectacular site to

637
00:36:47.840 --> 00:36:50.840
go searching for it in the night skies, but it

638
00:36:50.880 --> 00:36:54.800
doesn't end there. Another stunning object easily worth a look

639
00:36:54.960 --> 00:36:58.480
is the Red Spider nebula n GC sixty five three seven.

640
00:36:59.000 --> 00:37:02.159
It's a planetary nebul about eight thousand light years from Earth.

641
00:37:02.760 --> 00:37:05.360
It has a prominent two lobe shape, possibly due to

642
00:37:05.360 --> 00:37:08.159
a binary companion of magnetic fields and as an S

643
00:37:08.159 --> 00:37:11.400
shaped symmetry, with the lobes opposite each other appearing similar.

644
00:37:12.079 --> 00:37:14.760
This is believed due to the central companion to the

645
00:37:14.760 --> 00:37:18.639
central white dwarf. The central white dwarf, the remnant of

646
00:37:18.679 --> 00:37:22.159
the original star, produces a powerful and ten thousand degree

647
00:37:22.199 --> 00:37:25.159
hot three thousand killing meter a second stellar wind, which

648
00:37:25.199 --> 00:37:27.280
is generating one hundred billion killed me at a high

649
00:37:27.320 --> 00:37:30.559
waves of supersonic sharks formed as the local gas is

650
00:37:30.599 --> 00:37:34.079
being compressed and heated in front of the rapidly expanding lobes.

651
00:37:34.719 --> 00:37:37.639
Atoms caught in the shock waves are radiating invisible light,

652
00:37:37.800 --> 00:37:40.800
giving the nebula its unique spida like shape and also

653
00:37:40.840 --> 00:37:43.880
contributing to the expansion of the nebula. A star at

654
00:37:43.920 --> 00:37:46.119
the center of the red Spider nebula surrounded by a

655
00:37:46.199 --> 00:37:49.360
dust shell, making its exact prop but he's hard to determine.

656
00:37:49.719 --> 00:37:52.920
We think its surface temperatures probably somewhere around two hundred

657
00:37:52.920 --> 00:37:55.760
and fifty thousand degrees, although a temperature of up to

658
00:37:55.800 --> 00:37:58.559
five hundred thousand degrees can't be ruled out, and that

659
00:37:58.599 --> 00:38:00.079
would make it among the hottest one.

660
00:38:00.159 --> 00:38:01.079
Dwarf stars known.

661
00:38:01.800 --> 00:38:05.760
Looking directly south is the star Polaris Astrallus, or more

662
00:38:05.800 --> 00:38:09.079
accurately Sigma Octantius, the nearest star we have in the

663
00:38:09.119 --> 00:38:12.880
southern hemisphere to the south celestial pole, and consequently the

664
00:38:12.920 --> 00:38:17.159
closest counterpart we have to the north star Polaris. However,

665
00:38:17.360 --> 00:38:20.519
Sigma Octantus is far harder to see than Polaris because

666
00:38:20.559 --> 00:38:23.840
it's much fainter. Located some two hundred and seventy light

667
00:38:23.920 --> 00:38:26.679
years away, it's an orange giant reaching the end of

668
00:38:26.719 --> 00:38:29.880
its life. Turning to the southwest and just above the

669
00:38:29.920 --> 00:38:32.559
horizon this time of the year, we find Canopus, the

670
00:38:32.639 --> 00:38:36.159
second brighter star in the night sky after Sirius. It's

671
00:38:36.239 --> 00:38:38.599
located three hundred and ten light years away and is

672
00:38:38.639 --> 00:38:42.639
the brightest star in the constellation Carena. The kiel Canopus

673
00:38:42.719 --> 00:38:45.239
is a super giant some nine times the mass of

674
00:38:45.280 --> 00:38:47.880
the Sun and seventy one times its diameter.

675
00:38:49.039 --> 00:38:49.599
The month of.

676
00:38:49.599 --> 00:38:52.800
June also marks the first of two annual encounters with

677
00:38:52.920 --> 00:38:56.760
the Torred's meteor shower. The taureads are generated as the

678
00:38:56.760 --> 00:38:59.719
Earth passes through the debris stream created by the comet

679
00:38:59.719 --> 00:39:02.599
two Panche, which itself is thought to be a piece

680
00:39:02.599 --> 00:39:05.480
of a larger comet that broke apart somewhere between twenty

681
00:39:05.559 --> 00:39:09.119
thousand and thirty thousand years ago, most likely following numerous

682
00:39:09.119 --> 00:39:12.320
interactions with a powerful gravitational field of the king of

683
00:39:12.400 --> 00:39:16.880
planet Jupiter. As their name suggests, the Tourred's radiant, or

684
00:39:16.920 --> 00:39:20.039
apparent point of origin is in the direction of tourists.

685
00:39:20.079 --> 00:39:23.280
The ball the Turret's media shows unique in that it's

686
00:39:23.320 --> 00:39:26.320
made up of larger, more massive material pebbles instead of

687
00:39:26.440 --> 00:39:30.199
dust grains. Earth passes through the stream twice every year,

688
00:39:30.360 --> 00:39:34.159
once now in June, then again in October, called Halloween fireballs.

689
00:39:34.800 --> 00:39:38.280
The turreds release material birth by normal cometary activity and

690
00:39:38.360 --> 00:39:42.199
also occasionally by close encounters with the gravitational tidal force

691
00:39:42.280 --> 00:39:45.000
of the Earth and other planets, and this makes the

692
00:39:45.039 --> 00:39:49.320
Tourred stream of material the largest in the Inner Solar System. Now,

693
00:39:49.360 --> 00:39:52.000
since this stream of materials rather spread out in space,

694
00:39:52.119 --> 00:39:54.679
Earth will take several weeks to pass through it, causing

695
00:39:54.679 --> 00:39:57.480
an extended period of meta activity compared to the much

696
00:39:57.519 --> 00:40:02.079
smaller periods of activity associated with other meteor showers. Included

697
00:40:02.159 --> 00:40:05.519
in the stream is a denser flow of gravelly meteoroids

698
00:40:05.559 --> 00:40:08.599
called the Taurred Swarm, thought to be a ribbon of

699
00:40:08.719 --> 00:40:11.639
rocks roughly seventy five million by one hundred and fifty

700
00:40:11.639 --> 00:40:15.639
million kilometers across. Occasionally one hundred Earth passes through the

701
00:40:15.719 --> 00:40:19.320
larger meteoroids in the denser Taurred Swarm. In fact, one

702
00:40:19.320 --> 00:40:21.800
of the larger chunks of the Turret Swarm is now

703
00:40:21.880 --> 00:40:24.639
thought to have caused the infamous Tunguska event in the

704
00:40:24.639 --> 00:40:28.280
skies over Siberia back on June thirtieth, nineteen o eight.

705
00:40:28.880 --> 00:40:31.920
Astronomers believe the Tannguska event was the air burst of

706
00:40:31.960 --> 00:40:35.320
one hundred meters wide meteor over the Tannguska River region

707
00:40:35.320 --> 00:40:39.360
of Russia, causing mass devastation and flighttening over two thousand

708
00:40:39.400 --> 00:40:43.159
square kilometers of forest in the mattsticks. The blast was

709
00:40:43.280 --> 00:40:45.599
so bright it was enough to light up the night

710
00:40:45.639 --> 00:40:48.280
sky in London, a third of the way around the planet.

711
00:40:48.880 --> 00:40:53.639
Tuanguska remains the largest known Earth impact event in recorded history.

712
00:40:54.239 --> 00:40:56.679
It was considered a one in one thousand year event

713
00:40:56.760 --> 00:41:00.400
assuming a random distribution of events over time, but the

714
00:41:00.519 --> 00:41:03.119
new studies suggesting the event may have been caused by

715
00:41:03.119 --> 00:41:06.000
a turret swarm meteor and with the Earth passing through

716
00:41:06.039 --> 00:41:10.000
that swarm periodically, this tends to change those odds quite significantly.

717
00:41:10.800 --> 00:41:13.880
If the study is correct, this swarm heightens the possibility

718
00:41:13.880 --> 00:41:16.199
of a cluster of large impacts on the Earth over

719
00:41:16.239 --> 00:41:19.719
a very short period of time. For the complicating matters,

720
00:41:19.800 --> 00:41:23.559
the June Tourreds are actually two separate showers. The Southern

721
00:41:23.599 --> 00:41:26.360
Tourreds associated with the comet two p Nke or the

722
00:41:26.440 --> 00:41:29.920
Northern Tourrets originate from the asteroid two thousand and forty

723
00:41:30.079 --> 00:41:34.039
G ten and eccentric kilomet a wide asteroid plassified as

724
00:41:34.039 --> 00:41:37.719
an Earth object and potentially hazardous asteroid of the Apollo

725
00:41:37.760 --> 00:41:41.119
Group and joining us now for the rest of our

726
00:41:41.159 --> 00:41:43.840
tour of the June night skies. Seeing your science writer

727
00:41:43.960 --> 00:41:47.480
and Sky and Telescope magazine contributor Jonathan Nale, a student.

728
00:41:47.559 --> 00:41:49.800
Yet, well, we're almost midway through the year, and the

729
00:41:49.840 --> 00:41:52.199
sky has changed quite a lotically of the last few months,

730
00:41:52.239 --> 00:41:55.079
because you know, the constations of summer and lea, the

731
00:41:55.079 --> 00:41:57.880
southern summer had disappeared and northern winter had disappeared. And

732
00:41:57.880 --> 00:42:00.280
as the sun is shitting one of those constellations since

733
00:42:00.280 --> 00:42:02.920
Oryon is very low on the western horizon now and

734
00:42:02.960 --> 00:42:06.880
it's vanished and from view as each night passes nearby.

735
00:42:07.159 --> 00:42:08.519
A little bit higher in the sky, you've got the

736
00:42:08.519 --> 00:42:11.840
constellation Canus Major, but it's bright Stars series, the brightest

737
00:42:11.880 --> 00:42:14.440
star of the sky. That's still reasonably higher in the

738
00:42:14.440 --> 00:42:17.480
western sky, but it's sinking lower and lower night After that,

739
00:42:17.559 --> 00:42:20.039
that's it until the seasons are changing to its north.

740
00:42:20.320 --> 00:42:23.239
North from Canus Major, you've got a smaller cousin Canus Minor.

741
00:42:23.880 --> 00:42:27.199
There's the smaller dog it's still visible, and further north

742
00:42:27.320 --> 00:42:29.719
still from that, you've got the constellation Gemini, which is

743
00:42:29.760 --> 00:42:32.280
really easy to spot because it's got these two bright

744
00:42:32.320 --> 00:42:35.679
stars fairly close to each other, twin stars Castor and Pollus.

745
00:42:35.719 --> 00:42:38.039
That's where the Yea constellation gets the name for it

746
00:42:38.079 --> 00:42:40.320
that'll soon be gone as the weeks go by as well.

747
00:42:40.840 --> 00:42:43.480
On the pluff side though, with those constellations disappearing, but

748
00:42:43.519 --> 00:42:45.800
other ones are coming up in the eastern sky night

749
00:42:45.840 --> 00:42:48.480
after night as we roll further towards the middle of

750
00:42:48.519 --> 00:42:50.320
the year, and so we've got some of these really

751
00:42:50.320 --> 00:42:54.480
impressive constellations coming up, such as Scorpious and Sangittarius. Scorpius

752
00:42:54.559 --> 00:42:56.599
is a huge constellation that looks like its name, like

753
00:42:56.639 --> 00:42:59.960
a scorpion. Sagittarius is the constellation that's around the region

754
00:43:00.159 --> 00:43:02.239
of the center of our galaxies. So there are plenty

755
00:43:02.239 --> 00:43:03.920
of things to see there because we're looking into the

756
00:43:04.039 --> 00:43:06.199
thickest part of the Milky Way. And in the middle

757
00:43:06.199 --> 00:43:09.000
of the sky again towards the south, we've got other

758
00:43:09.239 --> 00:43:12.679
mighty constellations such as Centaurus. We've got Cruts or Cooks,

759
00:43:12.719 --> 00:43:16.159
the Southern Cross. You've got Veela, Karina, Lupas, and others. Now,

760
00:43:16.280 --> 00:43:18.159
a lot of people have never heard of those constellations,

761
00:43:18.199 --> 00:43:21.480
but regular stargaze is recognize them because all of those,

762
00:43:21.519 --> 00:43:23.920
in fact, all of the constellations I've mentioned, they live

763
00:43:24.039 --> 00:43:26.559
along the extent of the Milky Way, all very close

764
00:43:26.599 --> 00:43:28.800
to it. The Milky way, being that sort of fuzzy

765
00:43:28.920 --> 00:43:31.159
band of light you can see stretching across the night

766
00:43:31.199 --> 00:43:34.039
sky if you have dark enough sky conditions. So looking

767
00:43:34.079 --> 00:43:36.519
to the south, for us in the southern hemisphere, at

768
00:43:36.599 --> 00:43:38.519
least we've got the Southern Cross. Everyone wants to see

769
00:43:38.559 --> 00:43:40.760
the Southern Cross. It's about two thirds of the way

770
00:43:40.840 --> 00:43:43.119
up from the southern horizon at the moment. For once,

771
00:43:43.159 --> 00:43:45.039
it's standing upright, and it looks a bit like a

772
00:43:45.079 --> 00:43:47.159
Kite's got the shape of the kite, and it's quite small.

773
00:43:47.239 --> 00:43:50.559
The stars that comprise the Southern Cross, they're actually quite bright,

774
00:43:50.920 --> 00:43:53.519
So bear that in mind. I trying to have a

775
00:43:53.559 --> 00:43:56.239
look for it. It's small and it looks like a kite.

776
00:43:56.239 --> 00:43:58.119
And I wouldn't wait too long either, because as light

777
00:43:58.199 --> 00:44:00.880
delusion gets worse, we're seeing less and less of those

778
00:44:01.079 --> 00:44:01.840
five stars.

779
00:44:02.079 --> 00:44:04.360
The kite shape was made up of four bright stars,

780
00:44:04.360 --> 00:44:06.440
and there the fifth star that's in there as well,

781
00:44:06.639 --> 00:44:08.079
And for a lot of people in a lot of

782
00:44:08.119 --> 00:44:10.119
places now you can't see the fifth star anymore because

783
00:44:10.159 --> 00:44:13.280
it's the fainter of those five, and it's gone gone

784
00:44:13.320 --> 00:44:16.000
from view from the naked eye, which is really quite

785
00:44:16.079 --> 00:44:19.960
telling about the state of light pollution. Where most people live,

786
00:44:20.039 --> 00:44:23.079
particularly in a country like Australia where the vast majority

787
00:44:23.119 --> 00:44:25.199
of people living in what half a dozen big cities.

788
00:44:25.360 --> 00:44:28.519
So the light pollution is now so bad that we

789
00:44:28.559 --> 00:44:30.800
can't see one of the stars at Southern Cross, which

790
00:44:30.840 --> 00:44:33.519
is pretty disappointing if you asked me, and you're quite

791
00:44:33.599 --> 00:44:36.559
right that as it gets worse, even the brighter stars

792
00:44:36.599 --> 00:44:38.320
may one day gear. In fact, I saw a comment

793
00:44:38.360 --> 00:44:41.719
from someone recently on social media, someone visiting from Australia

794
00:44:41.760 --> 00:44:43.480
from China, i think, and they were saying, oh, ten

795
00:44:43.559 --> 00:44:45.320
things I've noticed about living in Australia, and one of

796
00:44:45.360 --> 00:44:47.880
them was I can see stars. I can actually see stars.

797
00:44:47.960 --> 00:44:51.719
That takes me right back to when the TV program Cosmos,

798
00:44:51.719 --> 00:44:53.960
presented by Carl Sagan back at right at the beginning

799
00:44:54.000 --> 00:44:56.039
of the nineteen eighty I remember reading that when that

800
00:44:56.119 --> 00:44:58.840
was shown around the world that producers of that program

801
00:44:59.000 --> 00:45:02.159
received lots of fanily. There's including fan letters from people

802
00:45:02.199 --> 00:45:05.840
in huge cities like Tokyo or pressures like that, and

803
00:45:06.800 --> 00:45:08.920
these people are saying, they're literally saying they didn't know

804
00:45:08.920 --> 00:45:10.719
the stars are real. They thought they had made up

805
00:45:10.719 --> 00:45:12.760
for science fiction because they had never seen stars.

806
00:45:12.800 --> 00:45:15.360
Well, there's that famous anecdote of people in New York

807
00:45:15.480 --> 00:45:19.039
during a major blackout ringing up emergency services and complaining

808
00:45:19.239 --> 00:45:21.400
because they can see all these stars in the sky

809
00:45:21.440 --> 00:45:22.360
and they didn't know what they were.

810
00:45:23.280 --> 00:45:24.800
This is the thing, This is the thing. People who

811
00:45:24.840 --> 00:45:27.920
live in the most massive cities are so much light pollution. Look,

812
00:45:28.039 --> 00:45:29.639
even where I live, there are knights. When I go

813
00:45:29.679 --> 00:45:30.760
out and I look up and I can see you

814
00:45:30.760 --> 00:45:34.239
have like a dozen stars, which is ridiculous when there

815
00:45:34.280 --> 00:45:38.039
are over the entire globe of the sky North More

816
00:45:38.039 --> 00:45:39.960
Southern Ministry at the whole life, only half of which

817
00:45:39.960 --> 00:45:41.800
you can see at any one time. Of course, over

818
00:45:41.840 --> 00:45:44.760
the entire globe, there's I think about five seven hundred

819
00:45:44.760 --> 00:45:47.440
stars that are bright enough to be made out individually

820
00:45:47.480 --> 00:45:50.440
binding by average eye sight, not counting all the medi

821
00:45:50.599 --> 00:45:52.440
billions of stars that make up the nookie way, which

822
00:45:52.480 --> 00:45:54.960
is that fuzzy glow that you can't you can't make

823
00:45:54.960 --> 00:45:57.480
out individual stars in there with just your own eyes,

824
00:45:57.599 --> 00:45:59.440
which and which you can do if you get out

825
00:45:59.440 --> 00:46:01.400
into a dead that were somewhere where there's no light

826
00:46:01.440 --> 00:46:04.840
around it. Oh yes, it's the most amazing. Yeah, that's

827
00:46:04.840 --> 00:46:05.559
that's what we're missing.

828
00:46:05.960 --> 00:46:08.400
That is what I used to work at a radio

829
00:46:08.440 --> 00:46:11.880
station in Darwin and would regularly commute between Darwen and Sydney,

830
00:46:11.880 --> 00:46:13.559
about a three thousand kilometer run.

831
00:46:13.599 --> 00:46:15.639
But do it over a couple of days and.

832
00:46:15.719 --> 00:46:18.199
The night skies as you drive up the Stuart Highway

833
00:46:18.280 --> 00:46:19.920
or absolutely brilliant.

834
00:46:19.920 --> 00:46:21.920
The sky is just a carpet of color.

835
00:46:22.079 --> 00:46:24.000
You know, this is this is one of the real

836
00:46:24.079 --> 00:46:28.320
tragedies of modern life that there's all sorts of fantastic

837
00:46:28.360 --> 00:46:31.920
things done in the environmental sector to preserve the lands

838
00:46:31.920 --> 00:46:34.000
and the waters and the forests and the trees and

839
00:46:34.320 --> 00:46:36.719
all that sort of stuff, which is fantastic, but not

840
00:46:36.880 --> 00:46:39.599
enough is yet being done to preserve our view of

841
00:46:39.639 --> 00:46:41.800
the night's dye, which sadly we're losing. There are a

842
00:46:41.840 --> 00:46:43.320
lot of good people doing a lot of good work

843
00:46:43.360 --> 00:46:45.800
on this, and there are dark sky regions and sights

844
00:46:45.800 --> 00:46:47.599
and things that have been set up all around the place,

845
00:46:47.639 --> 00:46:50.039
But for where the majority of people live, there's really

846
00:46:50.039 --> 00:46:52.119
not much hope at the moment, and I really can't

847
00:46:52.159 --> 00:46:54.960
see much changing. You go out into a desert and

848
00:46:55.079 --> 00:46:56.639
it's night time and you can see all the stars,

849
00:46:56.679 --> 00:46:59.679
and a cloud drifts by. You'll see a big black patch.

850
00:47:00.079 --> 00:47:03.280
The cloud will be a big black patch sliding above

851
00:47:03.320 --> 00:47:05.960
your head right and to block out the stars above.

852
00:47:06.000 --> 00:47:08.000
But in the city you see a cloud go past

853
00:47:08.000 --> 00:47:10.199
at nighttime and it's lit up like daylight. You can

854
00:47:10.239 --> 00:47:12.480
see the cloud, you know, like with a light gray

855
00:47:12.519 --> 00:47:14.920
color because it's picking up all this light that's coming

856
00:47:15.000 --> 00:47:16.920
up from all these lights on the ground below.

857
00:47:17.039 --> 00:47:18.119
And it's not just the cities.

858
00:47:18.239 --> 00:47:21.719
The Sighting Spring Observatory, for example, which is what seven

859
00:47:21.760 --> 00:47:25.679
hundred kilometers away nick knebarabran need Dubbo in the far

860
00:47:25.760 --> 00:47:28.719
west of New South Wales. The astronomers there can't turn

861
00:47:28.719 --> 00:47:32.199
the telescope east without seeing the lights of Sydney reflect

862
00:47:32.239 --> 00:47:34.079
off the clouds and off the air yep.

863
00:47:34.320 --> 00:47:37.000
And for quite a few decades now it's been the case. Anyway,

864
00:47:37.039 --> 00:47:38.800
back to those little points of light in the sky

865
00:47:38.840 --> 00:47:41.639
where was I was mentioned serious earlier, the brightest star

866
00:47:41.719 --> 00:47:43.760
in the sky, and the brightest star in the constellation

867
00:47:43.840 --> 00:47:47.039
came as major. The next brightest star in the United

868
00:47:47.079 --> 00:47:50.719
Sky is Canopus. That's the brightest star in Consternation Carina.

869
00:47:50.760 --> 00:47:52.760
And you can find this very low down in the

870
00:47:52.760 --> 00:47:54.880
south where if you're down here in the Southern hemisphere

871
00:47:54.960 --> 00:47:58.559
now compared to our sun Canopus is a superstar. It's

872
00:47:58.599 --> 00:48:01.079
about ten times as massive. Massive in the sense of

873
00:48:01.159 --> 00:48:04.480
its mass, not size in terms of size. It's about

874
00:48:04.519 --> 00:48:07.320
seventy times wider than our Sun, and it's about ten

875
00:48:07.559 --> 00:48:11.119
thousand times brighter than our Sun. Serious on the other hand,

876
00:48:11.360 --> 00:48:13.440
which is the brightest star we can see the night sky.

877
00:48:13.639 --> 00:48:15.639
It's only twenty five times as bright as the Sun,

878
00:48:15.760 --> 00:48:18.280
not ten thousand times, But it is much brighter in

879
00:48:18.280 --> 00:48:20.679
our sky than Canopus because it's a lot closer. It's

880
00:48:20.719 --> 00:48:22.599
only about eight and a half light years away, whereas

881
00:48:22.639 --> 00:48:24.840
Canopus is about three hundred and ten light years away.

882
00:48:24.920 --> 00:48:26.719
So a lot of these stars up there, you can't

883
00:48:26.719 --> 00:48:28.639
really tell from their brightness how far away they are,

884
00:48:28.719 --> 00:48:30.400
for some of them might be dim and close, and

885
00:48:30.400 --> 00:48:32.960
those might be bright but far away. In the northern

886
00:48:33.000 --> 00:48:34.639
part of the sky the moment of scenes from the

887
00:48:34.639 --> 00:48:37.079
Southern Hemist release, there are a couple of interesting bright stars.

888
00:48:37.119 --> 00:48:39.639
We've got Arkturists, which is about halfway up from our

889
00:48:39.639 --> 00:48:42.239
northern horizon and higher still in the night sky is

890
00:48:42.239 --> 00:48:45.079
one called Spiker. Ark Tourists is a red giant star.

891
00:48:45.119 --> 00:48:47.559
There's a couple of billion years older than our Sun.

892
00:48:47.639 --> 00:48:49.480
It's about the same mass as our Sun, but it's

893
00:48:49.519 --> 00:48:51.920
ballooned up to be about twenty five times bigger as well.

894
00:48:51.920 --> 00:48:55.079
If it's a big big star. Spiker is a binary

895
00:48:55.079 --> 00:48:57.440
star system who's just gone through to the interesting Spikeer's

896
00:48:57.440 --> 00:48:59.840
a binary star system who's pair of stars. They all

897
00:49:00.079 --> 00:49:02.800
each other so close to they're so close together, and

898
00:49:02.840 --> 00:49:05.039
they go around each other every four days. Mind you,

899
00:49:05.119 --> 00:49:07.840
they're so close together that their gravity, they're neutral gravity

900
00:49:07.880 --> 00:49:09.719
has pulled each of them out of shape, and so

901
00:49:09.800 --> 00:49:11.559
each of them is sort of like an egg shape

902
00:49:11.639 --> 00:49:14.320
rather than being traditional round star. Isn't it amazing? You

903
00:49:14.320 --> 00:49:16.639
can think that an entire star has been pulled out

904
00:49:16.639 --> 00:49:18.960
of shape by the gravity of another star right in

905
00:49:19.000 --> 00:49:21.679
next door, and they've spin around each other every four days.

906
00:49:21.679 --> 00:49:24.199
It's just mind bulb. Anyhow, as the night goes on,

907
00:49:24.480 --> 00:49:28.280
you'll see that things have changed. By midnight, Serious that's gone.

908
00:49:28.320 --> 00:49:30.000
That's set in the west, but not a couple of

909
00:49:30.000 --> 00:49:32.199
bright stars. They've got Viga and old Aar have appeared

910
00:49:32.199 --> 00:49:34.599
in the north way way way down in the southeast.

911
00:49:34.599 --> 00:49:37.440
We've got another star called Akana, another bright star that's

912
00:49:37.440 --> 00:49:39.360
turned up, that's come up over the east of horizon.

913
00:49:39.480 --> 00:49:42.159
All these changes of course occurred because the Earth is

914
00:49:42.199 --> 00:49:44.480
turning on a taxis and things that were below the

915
00:49:44.519 --> 00:49:47.320
horizon in the east have now come up into view,

916
00:49:47.480 --> 00:49:49.320
and the ones over in the west they're gone down

917
00:49:49.400 --> 00:49:52.079
out of you. Now, let's look at what the planets

918
00:49:52.079 --> 00:49:55.000
are doing this month. It's really quite interesting. At sunset

919
00:49:55.079 --> 00:49:56.800
at the beginning of the month, we've got Venus and

920
00:49:56.880 --> 00:49:59.559
Jupiter really prominent in the northwest, about a third of

921
00:49:59.599 --> 00:50:01.559
the way up on the horizon. Venus is the one

922
00:50:01.599 --> 00:50:03.639
that took down a bit lower and is brighter. Now,

923
00:50:03.719 --> 00:50:06.119
keep an eye on them, because night by night you'll

924
00:50:06.119 --> 00:50:08.760
see them appearing to move closer and closer to each other,

925
00:50:09.079 --> 00:50:12.000
and by the tenth of June they'll be side by

926
00:50:12.119 --> 00:50:13.840
side when you look on a star map. At least

927
00:50:13.840 --> 00:50:15.880
when you look on the real sky, there'll be several

928
00:50:15.880 --> 00:50:18.159
degrees apart. And then we can tell how much a

929
00:50:18.159 --> 00:50:20.199
degree is because the width of the moon is half

930
00:50:20.199 --> 00:50:23.079
a degree, so one degree is two moon wis apart,

931
00:50:23.159 --> 00:50:26.639
and you sat with several degrees apart. But also low

932
00:50:26.760 --> 00:50:29.639
down in the northwest there's another planet, Mercury, which starts

933
00:50:29.639 --> 00:50:31.920
the month quite low, but it's rising a little higher

934
00:50:31.960 --> 00:50:33.760
and higher ed to night and so by the time

935
00:50:33.880 --> 00:50:38.079
we get to the seventeenth, we'll have Mercury, Venus and

936
00:50:38.159 --> 00:50:40.360
Jupiter pretty much all together in the same part of

937
00:50:40.360 --> 00:50:43.079
the sky, and the Moon will have come along as well,

938
00:50:43.199 --> 00:50:45.519
so you'll have Mercury, Venus, the Moon, and Jupiter all

939
00:50:45.559 --> 00:50:47.440
arranged in the sort of the diamond shape. And on

940
00:50:47.480 --> 00:50:49.440
the following night, the Moon will have moved a bit

941
00:50:49.480 --> 00:50:51.880
in its orbit again, so the diamond samp will now

942
00:50:51.880 --> 00:50:54.119
have changed to a straight line. About all the four

943
00:50:54.239 --> 00:50:55.760
is things in a straight line, so that should be

944
00:50:55.800 --> 00:50:58.039
really impressive to see if you've got nice clear skies

945
00:50:58.159 --> 00:51:00.239
on the seventeenth and the eighteenth of the month. Now

946
00:51:00.280 --> 00:51:01.880
to see the other two bright planets, you're going to

947
00:51:01.920 --> 00:51:04.360
have to be up early because Shatun rises over the

948
00:51:04.360 --> 00:51:06.960
eastern horizon about two point thirty in the morning, followed

949
00:51:06.960 --> 00:51:09.079
by Mars a couple of hours later, So if you're

950
00:51:09.079 --> 00:51:10.719
an early riser to go to work for something, can

951
00:51:10.719 --> 00:51:12.800
get up a sixth prove or whatever before dawn when

952
00:51:12.800 --> 00:51:14.280
it's still dark, you should be able to see them

953
00:51:14.360 --> 00:51:16.679
quite easily. And finally Stewart on the twenty first bit,

954
00:51:16.760 --> 00:51:19.840
but the mid year salstice, it's the winter solstice for

955
00:51:19.920 --> 00:51:21.719
us in the southern Hemisphere and the summer solstice for

956
00:51:21.840 --> 00:51:23.400
our friends up in the North. So on this day

957
00:51:23.440 --> 00:51:25.760
the sun is at its most northerly point in the

958
00:51:25.800 --> 00:51:29.000
sky and the hours of darkness will be roughly longest

959
00:51:29.079 --> 00:51:30.639
on that day for us. You're in the shout and

960
00:51:30.760 --> 00:51:32.639
short stuff there in the North. And that's do. It's

961
00:51:32.639 --> 00:51:34.119
the night's stay forardon.

962
00:51:34.360 --> 00:51:37.199
That's senior science writer and skytte tell us Acout Magazine,

963
00:51:37.239 --> 00:51:56.239
contributed Jonathan Nelly, And this is space Time, and that's

964
00:51:56.280 --> 00:51:59.760
the show for now. Space Time is available every Monday,

965
00:51:59.760 --> 00:52:04.440
Wheay and Friday through bytes dot com, SoundCloud, YouTube, your

966
00:52:04.480 --> 00:52:08.199
favorite podcast download provider, and from space Time with Stuart

967
00:52:08.280 --> 00:52:12.079
Gary dot com. Space Time's also broadcast through the National

968
00:52:12.119 --> 00:52:16.119
Science Foundation, on Science Own Radio and on both iHeartRadio

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00:52:16.280 --> 00:52:19.159
and tune In Radio. And you can help to support

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00:52:19.199 --> 00:52:22.119
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00:52:22.159 --> 00:52:26.480
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972
00:52:26.599 --> 00:52:29.760
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973
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00:52:32.159 --> 00:52:35.079
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976
00:52:38.880 --> 00:52:41.440
with Stuart Gary dot com for full details.

977
00:52:42.239 --> 00:52:44.760
You've been listening to space Time with Stuart Gary.

978
00:52:45.400 --> 00:52:48.880
This has been another quality podcast production from bytes dot

979
00:52:48.880 --> 00:52:51.920
com