Feb. 26, 2026

Martian Gullies and Inside-Out Planets: Discoveries from the Cosmos

Martian Gullies and Inside-Out Planets: Discoveries from the Cosmos

Sponsor Link: This episode of SpaceTime is brought to you by Squarespace. Create your own exceptional website with ease at https://squarespace.com/spacetime. SpaceTime with Stuart Gary Gary - Series 29 Episode 25 In this episode of SpaceTime, we...

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Season 29
Sponsor Link:
This episode of SpaceTime is brought to you by Squarespace. Create your own exceptional website with ease at squarespace.com/spacetime.

SpaceTime with Stuart Gary Gary - Series 29 Episode 25
In this episode of SpaceTime, we explore the intriguing mysteries of Mars' gullies, uncover a unique inside-out planetary system, and witness the inaugural launch of Europe's most powerful rocket.
Mysterious Martian Gullies Explained
Scientists have made significant strides in understanding the enigmatic gullies on Mars, previously thought to be shaped by unknown forces. A new study published in Geophysical Research Letters reveals that blocks of frozen carbon dioxide are the culprits behind these formations. When the Martian winter sets in, CO2 ice accumulates and, upon warming, sublimates, creating gas pressure that carves deep gullies in the Martian surface. This groundbreaking phenomenon, likened to the sandworms of Dune, showcases a unique geological process not observed on Earth.
Inside-Out Planetary System Discovery
Astronomers have identified a remarkable new planetary system, catalogued as LHS 1903, that defies conventional models of planetary formation. Unlike our solar system, which features rocky planets close to the star and gas giants further out, LHS 1903 has a small rocky planet orbiting outside of two gas giants. This discovery, detailed in Science, suggests that this rocky world may have formed in a gas-depleted environment, challenging existing theories about how planets evolve and raising questions about the nature of planetary systems.
Europe's Powerful Rocket Launch
The European Space Agency has successfully launched the Ariane 64, its most powerful rocket to date, from the Kourou Spaceport in French Guiana. This inaugural mission, VA267, carried 32 satellites into orbit for Amazon's LEO network, marking a significant milestone as the largest number of satellites ever launched by an Ariane rocket. With plans for an average of 10 launches per year, the Ariane 64 is set to play a crucial role in the future of satellite deployment.
www.spacetimewithstuartgary.com
✍️ Episode References
Geophysical Research Letters, Science
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The Astronomy, Space, Technology & Science News Podcast.

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This is Spacetime Series twenty nine, episode twenty five, for

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broadcast on the twenty seventh of February twenty twenty six.

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Coming up on space Time, mysterious gullies on the red

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planet Mars that appeared to have been dug, the discovery

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of a unique inside out planetary system, and Europe's most

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powerful rocket undertakes its first launch. All that and more

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coming up on space Time.

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Welcome to space Time with Stuart Gary.

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Scientists have been studying a set of mysterious gullies on

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the red planet Mars that appear to have been excavated,

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raising questions of how now. A reporting the journal Geophysical

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Research Letters as determined the likely corporates aren't Martians, but

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rather block of frozen carbon dioxide the Steadies. Lead author

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Roneki Rolos from Utrek University says her tests showed how

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these blocks of CO two ice were able to dig

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gullies in a unique way. She says she felt like

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she was watching the sandworms in the movie June Now.

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Other researchers had previously suspected that these blocks could play

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a role in the formation of the gullies, but this

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is the first work to actually prove it. It's a

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phenomenon not seen on Earth, and it's never been observed

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by anyone previously.

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It works like this.

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Ice forms in the Martian Southern Hemisphere desert tunes during

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the winter. That's when temperatures can drop to minus one

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hundred and twenty degrees celsius. At this time, a layer

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of co two ice forms over the entire surface of

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the june field, sometimes up to seventy centimeters thick. Then,

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at the end of winter, the June slopes heat up

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and blocks of ice break off, some of which up

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to a meet along. Now, due to the thin Martian

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atmosphere and the large temperature differences between the warm June

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sand and the ice, the bottom of the ice immediately

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turns into a gas, a process called sublimation. Now, as

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a kilo of gas requires more space than the same

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way of ice, the gas pressure blasts away the sand

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around the block, causing the block itself to dig into

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the slope. It becomes trapped in a hollow surrounded by

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small ridges of settled sand. However, the sublimation process continues,

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and so the sand keeps on being plastered away in

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all directions. As a result, the block gradually moves downhill,

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leaving a long, deep gully behind it, with small sand

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ridges on either side. Once the block reaches the bottom

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of the slope and stops smoothing, the ice continues to

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supplimate until eventually all the seat is evaporated, and so

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all that remains is a hollow in the sand at

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the bottom of the dune. This space time still to

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come discoveries of a unique inside out planetary system, and

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Europe launches its most powerful ever rocket for the first time.

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All that and more still to cart on space time,

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Astronomers have discovered a distant planetary system that's turned scientists

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understanding of planetary formation inside out. Our Sun's planetary system

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consists of four inner terrestrial rocky worlds Mercury, Venus, Earth,

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and Mars, followed by the gas giants Jupiter, Satin. You're

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in a so neptune, but this newly observed system, cataloged

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as LHS nineteen oh three, is inside out, with a distant,

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small rocky planet orbiting outside of two gas giants. Now,

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a fourth planet in the system does all bit closer

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to the hearst Star than the big gas worlds, but

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it's still all very strange. The star LHS nineteen oh

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three is a special type M red dwarf located about

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one hundred and sixteen light years away. Traditional planetary system

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models based on our own Solar system obviously suggest that

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the closest planets to their host stars are rocky worlds

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because still a radiation sweeps away their gases atmospheres, leaving

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behind just dense rocky cores. As for the gas giants,

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they form further out in the cooler regions where gas

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can accumulate and so planets there can hold on to

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their extended atmospheres. Yet, the new findings were reported in

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the journal Science show this distant rocky world orbiting LHS

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nineteen o three, which appears to have either lost its

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gases atmosphere or never formed one in the first place.

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Astronomers made their discovery in data from ESA's KEIOPS characterizing

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Exoplanets satellite. The studies lead author Thomas Wilson from the

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University of Warwick says this strange object makes it a

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unique inside out system. Rocky planets usually don't form far

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away from the home star beyond the gas giants, so

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Wilson and colleagues have set out to explore various possible

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explanations for how this robe rocky planet could have formed.

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Could the rocky planet have simply been flung out there

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through gravitational perturbations, or did it lose its atmosphere in

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some cataclysmic collision. After careful consideration, the authors eventually ruled

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out both these hypotheses. Instead, they found evidence that these

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four planets didn't all form at the same time as

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one would expect, but formed one after the other in

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a process called inside out planetary formation. If LHS nineteen

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oh three gave birth to its four planets one after

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the other, from the inner to the outermost planet, then

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each planet evolves in turn, swooping up nearby gas and

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dust and leaving further out planets to wait and potentially

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evolve in a different environment. Wilson says this means that

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by the time the final outer planet formed, the system

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may simply have already run out of gas, which is

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considered vital for planetary formation. Yet here it is a small,

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rocky world, defying explanations. He says, it seems that we've

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found the first evidence of a planet that's formed in

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a gas deplated environment. So this small rocky outer planet

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simply be an odd exception, or it may be the

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first clue of a new pattern of how planetary systems

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can evolve. Either way, it's a discovery begging for an

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explanation that lies beyond sciences typical understanding of planetary formation.

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This is space Time.

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Still to com Europe's most powerful rocket undertakes its first launch,

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and the March Equinox, the constellations of tourists, The Bull

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and Leo, the Lion, and three point one four one

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five nine Pie Day are among the highlights of the

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March Night skies on SkyWatch. This episode of Space Time

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is brought to you by square Space, the platform that

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the scheduling crumbs, the unpaid invoices under the couch, and

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actually answers the door when customers knock. If you offer services, insulting, classes, events,

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whatever you call your expertise. Square space maxbooking and getting

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paid straightforward, built in appointment scheduling, professional invoices and secure

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will actually find you. Square space is built in SEO

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slash space time and the promo code space time and

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remember you'll find the links in our show notes. Arion

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Space is undertaking the inaugural launch of the new Arian

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sixty four, Europe's most powerful ever rocket. Mission VA two

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sixty seven from the European Space Agency's Spaceport in Front

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carried thirty two satellites into orbit for the Amazon Leo network,

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which aims to eventually rival Elon Musk Starlink. It's the

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largest number of satellites ever carried by an Ariane rocket

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and it carries such a massive load. The Arian six

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was fitted with four strap on solid rocket boosters rather

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than the two used on the six previous flights of

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the new launch vehicle. Amazon now has one hundred and

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seventy five broadband satellites in orbit, with plans to eventually

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expand the constellation to some three thousand, two hundred now

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rival Starlink already has nine four hundred satellites orbiting the planet.

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After its initial launch in twenty twenty four, the new

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Arian six rocket undertook five flights last year. Arian Space

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and the European Space Agency eventually planned to have Arian

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six undertake an average of ten launches a year. This

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is space time, and time that'd turn our eyes to

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the skies and check out the celestial sphere for March

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on SkyWatch. Happy New Year, Well it would be if

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this was ancient Mesopotamia or Rome. That's because March was

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the first month of the new year. Going back to

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the earliest concept of celebrating New Year's Day at the

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time of the vernal equinox around two thousand BCE. See

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the ancient Roman calendar, which had just ten months, designated

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March first as the new year. That ten month calendar

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is still reflected today, with the name September or septemb

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being Latin for seven October Octo, meaning eight November and

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November nine and December of DECI meaning ten who wasn't

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really until the Gregorian calendar that January first mark the

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start of the new year, But in the beginning it

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was mostly Catholic countries that adopted it. Protestant nations only

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gradually moved across, with the British, for examp, not adopting

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the reformed calendar until seventeen fifty two. Prior to that date,

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the British Empire and its American colonies still celebrated New

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Year's Day on March twenty fifth. The heart of the

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month is the March equinox, which will take place at

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one forty six in the morning of Saturday March the

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twenty first Australian Eastern daylight time. That's ten forty six

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in the morning of Friday, March the twentieth the US

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Eastern daylight time, and two forty six in the afternoon

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Greenwich meantime. For our listeners in the northern Hemisphere, it

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means the vernal equinox, the start of spring, although south

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of the equator it's the autumnel equinox, meaning a move

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into autumn. The day marks the point in orbit around

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the Sun when the planet's rotational axis means the Sun

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will appear to rise exactly due east and set exactly

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due west to someone standing on the equator, it means

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almost equal hours of darkness and light. In fact, the

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very word equinox is derived from the Latin meaning qwie

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or equal, and knox meaning night. It all comes about

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because Earth's rotational axis is tilted at an angle of

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around twenty three point four degrees in relation to the ecliptic,

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the plane created by Earth's orbit around the Sun. That

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axial tilt is always pointed at the same position in

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the sky, regardless of Earth's orbit position around the Sun,

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so on any other day of the year, either the

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northern or southern hemisphere it tilted more towards the Sun,

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But on the two equinoxes, usually around March twenty first

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and September twenty thirty each year, the tilt of Earth's

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axis is directly perpendicular to the Sun's rays. However, there's

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a complication called procession. This causes Earth's spin axis to

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wobble ever so slightly, just like the axle of a

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spinning top. The rate of procession is only about half

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a degree per century. So people don't notice it on

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human timescales. And because the direction of Earth's axis of

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rotation determines at which point in Earth's orbit the seasons occur,

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precession will cause a particular season, for example, the southern

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Hemisphere autumn to occur at a slightly different place from

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year to year over a twenty one thousand year cycle.

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At the same time, Earth's orbit itself is subjected to

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small changes called perturbations see Earth's orbits and the lips,

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and there's a slow change in its orientation which gradually

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shifts the point of perihelion, Earth's closest dobital position to

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the Sun. Now, these two effects, the procession of the

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axis of rotation and the change in the orbit's orientation,

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work together to shift the seasons with respect to perihelion.

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And because we use a calendar year that's aligned to

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the occurrence of the seasons, the date of perihelion gradually

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regresses through a twenty one thousand year cycle. And there's

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another complication. Australia and some of the other Commonwealth countries

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start their seasons on the first day of the month,

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what are referred to as meteorological seasons. Rather than on

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the solstice season equinoxes, which are referred to as astronomical seasons,

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so that means Australia's autumn officially began on March first,

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rather than on the day of the March equinox. Meteorological

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seasons are used because it makes it easier for meteorologists

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and climatologists to break the seasons down into more exact

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three month calendar groupings for comparing seasonal and monthly statistics.

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The moment of the March equinox is also important in

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astronomy because it's used to define the celestial coordinate system

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of right ascension and declination. In astronomy, the celestial coordinate

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system is the astronomical equivalent to the latitude and longitudinal

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coordinates used on Earth's surface. It's used to specify the

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position of objects in three dimensional space and the direction

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of those objects on the celestial sphere, the imaginary globe

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surrounding the Earth. In other words, it lets scientists determine

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the position of a celestial object such as a satellite,

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are planet, stars, galaxies, and so on. Right ascension, which

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uses the symbol alpha, is the angular distance measure eastwards

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along the celestial equator from the vernal equinox on the

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celestial sphere. Its analogous to terrestrial longitude declination, which uses

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the symbol delta measures the angle north or south of

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the celestial equator, and so it's the celestial equivalent to

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terrestrial latitude markie. The vernal equinoxen setting in the western

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evening sky this time of year is one of the

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oldest recognized constellations in the heavens. Taurus the Bull, so

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named around six thousand years ago in Greek mythology, Taurus

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represents the king of the god Zeus. Zeus lasted after

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King Ajino's daughter Europa, who was looking after a herd

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of cattle. Now, being a god and with god like powers,

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Zeus decided to transform himself into a powerful white ball

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so that he could get closer to the beautiful Europa.

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Now once transformed into a ball, Zeus convinced Europe to

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climb on his back, and he then carried her off

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to the island of Crete. Taurus has said is represented

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by a dominant V shaped grouping of stars. The bright

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ready star in the group is Aldebaran, an orange giant

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00:14:55.799 --> 00:14:57.559
one and a half times the mass of the Sun,

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located sixty.

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Five light years away.

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A light year is about ten trillion kilometers, the distance

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of Perdon can travel in a year at three hundred

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00:15:05.679 --> 00:15:08.960
thousand kilometers per second, the speed of light in a vacuum,

251
00:15:09.000 --> 00:15:12.440
and the ultimate speed limit of the universe. Alibran is

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the fourteenth brightest star in the night sky and the

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00:15:15.080 --> 00:15:17.960
closest bright star at the point of the vernal equinox.

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00:15:18.559 --> 00:15:21.879
In ancient Arabic, Order Bran's name means the follower, as

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it appears to follow the seven sisters of the Plates.

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00:15:25.399 --> 00:15:27.799
It's also the first of the four royal or guardian

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stars identified by the ancient Mesopotamians. Now, that v shaped

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00:15:32.440 --> 00:15:35.559
grouping of stars knee Alibaran is known as the Hyades.

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00:15:36.240 --> 00:15:39.480
It's the nearest young open star cluster to Earth, Located

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just one hundred and fifty three light years away. Between

261
00:15:42.840 --> 00:15:46.360
Orderbran and the Orian constellation, you'll see a bright red

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star that's Bettlegoes, the ninth brightest star in the night

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00:15:49.600 --> 00:15:53.159
sky these days, more commonly called Beetlejuice.

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00:15:53.240 --> 00:15:54.039
If you turn to the.

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00:15:54.000 --> 00:15:57.440
North now, you'll see the two bright stars Pollux and Casta,

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00:15:57.639 --> 00:16:01.799
which represent the northern constellation. Of Gemini, the twins. In

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Greek mythology, they were brothers who traveled with Jason aboard

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00:16:05.000 --> 00:16:08.240
the ship Argo in search of the Golden Fleece. Poul

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00:16:08.320 --> 00:16:11.840
Axe is an orange hued evolved giant star located thirty

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00:16:11.840 --> 00:16:15.120
four light years away. It has about twice the Sun's

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00:16:15.200 --> 00:16:18.039
mass and has bloated out to around eleven times the

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00:16:18.120 --> 00:16:21.600
Sun's diameter. In two thousand and six, an extra solar

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planet or exoplanet, designated Polax B was discovered orbiting the star.

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00:16:26.679 --> 00:16:29.519
The planet is a gas giant, orbiting its host star

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00:16:29.639 --> 00:16:33.320
every one point sixty one earth years. The other star, Casta,

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00:16:33.559 --> 00:16:36.159
is located some fifty one light years away, and it's

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00:16:36.240 --> 00:16:40.159
actually a system of six stars comprising three eclipsing binaries.

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00:16:40.720 --> 00:16:44.240
Eclipsing binaries the binary star systems, in which the orbital

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00:16:44.279 --> 00:16:46.519
plane of the two stars and the system lies so

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00:16:46.759 --> 00:16:49.279
nearly along the line of sight from the observer here

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00:16:49.320 --> 00:16:51.840
on Earth that the stars appear to eclipse each other.

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00:16:52.840 --> 00:16:55.000
Looking to the northeast now, and you'll see the star

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00:16:55.120 --> 00:16:58.679
Regulus or Little King, the brightest star. The constellation Leo.

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00:16:58.799 --> 00:17:02.559
The Lion is mentioned by Homer in his famous eighth

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00:17:02.559 --> 00:17:06.839
century BCE polm the Odyssey. According to Greek mythology, Leo

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00:17:07.039 --> 00:17:10.319
was killed by Hercules as the first of his twelve labors.

287
00:17:10.880 --> 00:17:14.039
Located some seventy nine light years away, Regulus is a

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00:17:14.119 --> 00:17:18.400
modible star system composed of at least four stars. Regulus,

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00:17:18.440 --> 00:17:22.759
a designated Alpha Liernus, is a spectroscopic binary comprising a

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00:17:22.839 --> 00:17:26.279
rapidly spinning spectral type B blue white star around three

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00:17:26.279 --> 00:17:28.319
and a half times more massive than the Sun with

292
00:17:28.440 --> 00:17:31.079
some two hundred and eighty eight times the Sun's luminosity,

293
00:17:31.640 --> 00:17:35.119
and a small companion star, most likely a white dwarf.

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00:17:35.319 --> 00:17:37.519
There's still a corpse of what once would have been

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00:17:37.559 --> 00:17:40.920
a Sun like star. The pair take about forty days

296
00:17:40.960 --> 00:17:44.920
to orbit each other. Spectroscopic binaries a double star systems

297
00:17:45.039 --> 00:17:47.519
orbiting each other so closely and at such an angle

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00:17:47.599 --> 00:17:50.720
that they can only be visually separated from our viewpoint

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00:17:50.720 --> 00:17:55.079
here on Earth, at least by their spectroscopic signatures. Astronomers

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00:17:55.079 --> 00:17:58.920
describe stars in terms of spectral types. It's a classification

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00:17:59.039 --> 00:18:02.359
system based on ten which are and characteristics. The hottest,

302
00:18:02.440 --> 00:18:05.640
most massive, and most luminous stars are known as spectual

303
00:18:05.720 --> 00:18:09.359
type O blue stars. They're followed by spectual type B

304
00:18:09.359 --> 00:18:13.240
blue white stars, then specual type A white stars, spectual

305
00:18:13.319 --> 00:18:17.440
type F whitish yellow stars, then spectual type G yellow stars.

306
00:18:17.559 --> 00:18:20.559
That's where our sun fits in. Then there's spectual type

307
00:18:20.640 --> 00:18:23.599
K orange stars, and the coolest and least massive of

308
00:18:23.640 --> 00:18:27.640
all stars are specual type M red stars, commonly referred

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00:18:27.640 --> 00:18:31.319
to as red dwarfs. Each specual classification system is further

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00:18:31.400 --> 00:18:35.359
subdivided using a numeric digit to represent temperature, with zero

311
00:18:35.480 --> 00:18:38.000
being the hottest and nine the coolest, and then you

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00:18:38.039 --> 00:18:42.640
add a Roman numeral to represent luminosity. So our Sun

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00:18:42.759 --> 00:18:46.079
technically is a G two val G two five.

314
00:18:46.079 --> 00:18:47.039
Yellow dwarf star.

315
00:18:47.839 --> 00:18:51.319
Also included in the stellar classification system are special types

316
00:18:51.480 --> 00:18:54.799
LT and Y, which are assigned to feldstars known as

317
00:18:54.839 --> 00:18:57.880
brown dwarves, some of which were born as specual type

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00:18:58.000 --> 00:19:01.240
M red dwarf stars but became brown dwarfs after losing

319
00:19:01.240 --> 00:19:04.359
some of their mass. Brown dwarves fit into a unique

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00:19:04.359 --> 00:19:07.599
category between the largest planets, which can have around thirteen

321
00:19:07.599 --> 00:19:10.400
times the mass of Jupiter, and the smallest spectual type

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00:19:10.480 --> 00:19:13.440
M red dwarf stars, which are around seventy five to

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00:19:13.480 --> 00:19:16.359
eighty times the mass of Jupiter or about zero point

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00:19:16.440 --> 00:19:20.039
zero eight solar masses. The primary star in now for

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00:19:20.119 --> 00:19:23.240
the earnest, completes a full rotation around its axis in

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00:19:23.319 --> 00:19:27.039
under sixteen hours. That's incredibly quick, especially when compared to

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00:19:27.039 --> 00:19:30.519
our Sun's thirty day rotational period. Now this gives the

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00:19:30.519 --> 00:19:33.640
primary star an oblate appearance, and it causes what's known

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00:19:33.640 --> 00:19:37.319
as gravity darkening, meaning its poles are considerably hotter and

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00:19:37.440 --> 00:19:41.359
five times brighter per unit surface area than its equatorial region.

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00:19:42.000 --> 00:19:45.599
Scientists estimate that if it were rotating just fifteen percent faster,

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00:19:45.839 --> 00:19:48.799
the star's gravity would be insufficient to hold it together

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00:19:48.960 --> 00:19:53.240
and it would literally spin itself apart. Located further away

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00:19:53.319 --> 00:19:57.480
at Regulus BCND, which are all dim main sequence stars.

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Main Sequence stars are those undergo showing hydrogen fusion into

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00:20:01.599 --> 00:20:04.400
heal him in their core, like the Sun's currently doing.

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00:20:05.039 --> 00:20:07.519
Regulus B and C are thought to orbit each other

338
00:20:07.559 --> 00:20:10.440
every six hundred earth years and are located around five

339
00:20:10.519 --> 00:20:15.279
thousand astronomical units away from Regular SA. An astronomical unit

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00:20:15.359 --> 00:20:17.640
is the average distance between the Earth and the Sun,

341
00:20:17.839 --> 00:20:20.880
around one hundred and fifty million kilometers or eight point

342
00:20:20.920 --> 00:20:24.480
three light minutes. Regular SP is a spectrol type F

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00:20:24.559 --> 00:20:28.000
white yellow star, while its companion Regular C is a

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00:20:28.000 --> 00:20:31.680
small spectral type M red dwarf star. Regulus D is

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00:20:31.720 --> 00:20:33.920
a bit more of a question mark. It's a dim star,

346
00:20:34.319 --> 00:20:36.319
and at least from our point of view, it appears

347
00:20:36.319 --> 00:20:38.440
to be sharing motion across the sky with.

348
00:20:38.480 --> 00:20:39.599
Other members in the group.

349
00:20:40.279 --> 00:20:43.000
At the opposite end of the constellation of Regulus is

350
00:20:43.039 --> 00:20:47.119
the star Beatterleerness or Dinebola, the Horse's Tail. It's a

351
00:20:47.200 --> 00:20:50.559
luminous white star thought to be spectual type A, about

352
00:20:50.559 --> 00:20:53.039
half as bright as Regulus and the third brightest star

353
00:20:53.119 --> 00:20:56.839
in the constellation Leo. Bitter Leona says about one point

354
00:20:56.880 --> 00:20:59.400
eight times the mass of the Sun and about fifteen

355
00:20:59.440 --> 00:21:03.200
times the Sun's luminosity. It's suspected of being a dwarf

356
00:21:03.240 --> 00:21:07.160
cepide or Deeta scuty type variable star, meaning its luminosity

357
00:21:07.319 --> 00:21:09.960
varies very slightly over a period of several hours due

358
00:21:09.960 --> 00:21:13.000
to pulsations on its surface. Also at the other end

359
00:21:13.039 --> 00:21:16.839
of Leo other stars theater and loterlyoners the loins of

360
00:21:16.880 --> 00:21:20.200
the lion. Theaterlyess is about one hundred and sixty five

361
00:21:20.279 --> 00:21:23.960
light years away. It's a very young spectrotype a white

362
00:21:24.039 --> 00:21:26.319
star about two and a half times the mass of

363
00:21:26.319 --> 00:21:28.880
the Sun, with an age of just five hundred and

364
00:21:28.960 --> 00:21:33.000
fifty million years. Theatreally eerness a spectra shows enhanced absorption

365
00:21:33.119 --> 00:21:36.759
lines for metals, that is, elements other than hydrogen and helium.

366
00:21:37.119 --> 00:21:40.559
This increased metallicity appears around twelve percent higher than the Sun,

367
00:21:40.839 --> 00:21:43.160
allowing the star to radiate with some one hundred and

368
00:21:43.160 --> 00:21:45.599
forty one times the luminosity of the Sun from its

369
00:21:45.599 --> 00:21:48.599
outer atmosphere at an effective temperature of nine thy three

370
00:21:48.640 --> 00:21:51.839
hundred and fifty keelven, literally giving it a white hot glow.

371
00:21:52.559 --> 00:21:55.839
Located some seventy nine light years away, lotally Onness is

372
00:21:55.880 --> 00:21:59.480
another spectroscopic binary consisting of two stars orbiting each other

373
00:21:59.559 --> 00:22:02.400
every one one hundred and eighty three earth years. The

374
00:22:02.440 --> 00:22:05.960
primary star is a spectrotype F yellow dwarf star, a

375
00:22:05.960 --> 00:22:06.799
little hotter.

376
00:22:06.559 --> 00:22:07.839
And more massive than the Sun.

377
00:22:08.519 --> 00:22:11.599
Algebra or gammily Ernest is a binary star system with

378
00:22:11.640 --> 00:22:15.279
a visible third component. The two primary stars are located

379
00:22:15.319 --> 00:22:17.480
one hundred and twenty six light years away and can

380
00:22:17.519 --> 00:22:21.519
be resolved in a backyard telescope. Both are yellow giants,

381
00:22:21.720 --> 00:22:25.279
orbiting each other every six hundred earth days. The unrelated

382
00:22:25.359 --> 00:22:28.839
tertiary star named fortyle Earns is a yellow tin star

383
00:22:28.920 --> 00:22:32.720
which can be seen through binoculars. Its traditional name Algebra,

384
00:22:32.920 --> 00:22:36.720
means the forehead. Other stars in the system include Diltterleerness

385
00:22:36.759 --> 00:22:39.200
or Zosma, which is a blue white star fifty eight

386
00:22:39.279 --> 00:22:42.200
light years from Earth, Epsilonly Earnest, a yellow giants some

387
00:22:42.200 --> 00:22:44.279
two hundred and fifty one light years from Earth, and

388
00:22:44.400 --> 00:22:48.200
Zeally Earnes and optical triple Star. The brightest component is

389
00:22:48.200 --> 00:22:50.400
a white giant about two hundred and sixty light years

390
00:22:50.400 --> 00:22:53.319
from Earth, while the second brighter star, thirty nine Earnest,

391
00:22:53.480 --> 00:22:56.079
is widely spaced and is located to the south of

392
00:22:56.119 --> 00:22:59.079
the primary, with the third and faintest star in the system,

393
00:22:59.200 --> 00:23:03.079
thirty five Lye, located to the north. Also located in

394
00:23:03.160 --> 00:23:06.960
Leo is Taulenus, visible as a double star through binoculars.

395
00:23:07.480 --> 00:23:09.960
It includes a yellow giant located some six hundred and

396
00:23:09.960 --> 00:23:12.839
twenty one light years from Earth, and a binary secondary

397
00:23:12.880 --> 00:23:15.759
star fifty four Learners, a pair of blue white stars,

398
00:23:15.799 --> 00:23:18.519
the visible in small telescopes and located two hundred and

399
00:23:18.559 --> 00:23:22.519
eighty nine light years from Earth. Also in the constellation Leo,

400
00:23:22.799 --> 00:23:26.039
you'll find the Leo triplet, a group of three galaxies

401
00:23:26.160 --> 00:23:30.559
Messia sixty five, Messia sixty six, and NNGC thirty six

402
00:23:30.680 --> 00:23:35.200
twenty eight, all appearing relatively close together. Messia sixty five,

403
00:23:35.279 --> 00:23:38.279
also known as MNGC thirty six twenty three, is an

404
00:23:38.279 --> 00:23:43.160
intermediate spiral, possibly barred spiral galaxy about thirty seven million

405
00:23:43.240 --> 00:23:46.519
light years away. M sixty five disc appears to be

406
00:23:46.559 --> 00:23:50.400
slightly warped, and a relatively recent burst of star formation

407
00:23:50.720 --> 00:23:53.559
is suggestive for some gravitational interaction with the other two

408
00:23:53.599 --> 00:23:56.599
galaxies in the Leo triplet, possibly around eight hundred million

409
00:23:56.720 --> 00:24:01.519
years ago. Nearby is MESSI sixty six NNGC thirty six

410
00:24:01.599 --> 00:24:05.720
twenty seven, another intermediate spiral galaxy some ninety five thousand

411
00:24:05.759 --> 00:24:08.920
light years wide and about thirty six million light years away.

412
00:24:09.559 --> 00:24:13.119
Gravitational interaction from its passing carters with the neighboring galaxies

413
00:24:13.119 --> 00:24:17.279
in the triplet has resulted in extremely high central mass concentration,

414
00:24:17.599 --> 00:24:20.880
a high molecular to atomic mass ratio, and a resolved,

415
00:24:20.880 --> 00:24:24.640
non rotating clump of neutral atomic hydrogen apparently removed from

416
00:24:24.680 --> 00:24:27.559
one of its spiral arms. The third member in the

417
00:24:27.599 --> 00:24:31.559
group is NGC thirty six twenty eight. The Hamburger Galaxy,

418
00:24:31.839 --> 00:24:35.200
a spiral galaxy with a spectacular three hundred thousand light

419
00:24:35.240 --> 00:24:39.440
year long tidal trail of gas and stars. MGC thirty

420
00:24:39.440 --> 00:24:42.599
six twenty eight is located thirty five million light years away.

421
00:24:43.200 --> 00:24:46.599
Its most conspicuous feature is the broad and obscuring band

422
00:24:46.640 --> 00:24:49.519
of dust located along the outer edge of its spiral arms,

423
00:24:49.519 --> 00:24:54.720
effectively transsecting the galaxy to the view from Earth. Other bright,

424
00:24:54.759 --> 00:24:59.119
well known galaxies in LEO include Messia ninety five, Messia

425
00:24:59.200 --> 00:25:03.279
ninety six, mess one hundred and five, and NGC twenty

426
00:25:03.359 --> 00:25:06.759
nine oh three. M ninety five and M ninety six

427
00:25:06.799 --> 00:25:10.319
are both spiral galaxies, each about twenty million light years

428
00:25:10.319 --> 00:25:14.799
from Earth. M ninety five is a bad spiral. Another

429
00:25:14.880 --> 00:25:18.799
bad spiral galaxy is NNGC twenty nine oh three, which

430
00:25:18.839 --> 00:25:21.559
is thought to be very similar in size and structure

431
00:25:21.720 --> 00:25:25.279
to our own Milky Way galaxy. It was discovered by

432
00:25:25.359 --> 00:25:29.079
William Herschel in seventeen eighty four. Close to the M

433
00:25:29.200 --> 00:25:32.559
ninety five M ninety six pair is the elliptical galaxy

434
00:25:32.759 --> 00:25:35.559
M one oh five, which is also around twenty million

435
00:25:35.640 --> 00:25:38.839
light years from Earth. Okay, let's turn to the east

436
00:25:38.880 --> 00:25:43.000
now and the constellation of Corvus the crow in Greek mythology.

437
00:25:43.160 --> 00:25:45.480
Corvs was a really clever crow. In fact, he could

438
00:25:45.519 --> 00:25:48.640
talk to people. However, after refusing to speak to the

439
00:25:48.680 --> 00:25:51.960
god Apollo, he was banished to the sky together with

440
00:25:52.079 --> 00:25:55.400
Creter the carpet Hydra the snake. One of the brightest

441
00:25:55.400 --> 00:25:58.559
stars in Hydra is al Fad, the solitary one, so

442
00:25:58.799 --> 00:26:03.079
named because it appear is all alone in the sky. Okay,

443
00:26:03.160 --> 00:26:05.519
turning to the western horizon now, and you'll see the

444
00:26:05.559 --> 00:26:08.759
star Akina in the southern tip of the constellation Eridanus.

445
00:26:08.839 --> 00:26:11.799
The river Eridanus is one of the largest and longest

446
00:26:11.839 --> 00:26:15.319
constellations in the sky. Akina means the river's end, as

447
00:26:15.359 --> 00:26:19.039
it marks the end of the River Eridanus, located around

448
00:26:19.039 --> 00:26:21.599
one hundred and thirty nine light years away. Akina is

449
00:26:21.599 --> 00:26:25.359
a binary star system comprising two stars, Alpha Ridney A

450
00:26:25.519 --> 00:26:28.920
and Alpha Rhydney B, one of the ten apparent brightest

451
00:26:28.960 --> 00:26:32.079
stars in the night sky. Alpha Orridney A is a young,

452
00:26:32.240 --> 00:26:35.480
hot spectual type B blue star about six point seven

453
00:26:35.519 --> 00:26:37.920
times the mass of the Sun with a stunning three

454
00:26:38.400 --> 00:26:41.960
one hundred and fifty times the Sun's luminosity. Akina is

455
00:26:42.039 --> 00:26:45.559
extremely high rotational velocity of over sixteen kilometres per second

456
00:26:45.680 --> 00:26:48.079
gives it an oblate shape, making it one of the

457
00:26:48.119 --> 00:26:51.000
least veherical stars in the Milky Way, with an equatorial

458
00:26:51.000 --> 00:26:54.400
diameter some fifty six percent greater than its polar diameter.

459
00:26:54.960 --> 00:26:59.680
This distorted shape means the star displays significant latitudinal temperature variations,

460
00:27:00.119 --> 00:27:03.200
its polar temperature being above twenty thousand kelvin, while its

461
00:27:03.240 --> 00:27:06.680
equatorial temperature, being much further away from the stollar core,

462
00:27:06.839 --> 00:27:10.480
is only around ten thousand kelvin. Those high polar temperatures

463
00:27:10.480 --> 00:27:13.759
are generating a fast polar wind, ejecting matter from the

464
00:27:13.799 --> 00:27:17.559
star and generating a polar envelope of hot gas and plasma.

465
00:27:18.119 --> 00:27:21.079
The companion star Alfur Ridney B appears to be a

466
00:27:21.119 --> 00:27:24.000
spectro type, a white star with about twice the mass

467
00:27:24.000 --> 00:27:26.880
of the Sun. The two stars orbit each other at

468
00:27:26.880 --> 00:27:32.799
an average distance of roughly twelve point three astronomical units. Now,

469
00:27:32.839 --> 00:27:36.119
just a quick reminder that March fourteenth marks the yearly

470
00:27:36.200 --> 00:27:40.519
celebration of the mathematical constant pi. Pi is the ratio

471
00:27:40.599 --> 00:27:44.039
of a circle's circumference to its diameter, but it's also

472
00:27:44.160 --> 00:27:48.039
an irrational number, meaning its decimal representation never ends and

473
00:27:48.160 --> 00:27:51.880
never repeats more than just a number. Pi has important

474
00:27:51.880 --> 00:27:56.160
applications in astrophysics. Orbital mechanics and other fields of astronomy.

475
00:27:56.720 --> 00:27:59.680
It's been calculated to over a trillion digits, and the

476
00:28:00.200 --> 00:28:03.039
record for a sighting part from memory is over seventy

477
00:28:03.200 --> 00:28:06.400
thousand digits. Imagine sitting next to that person at a

478
00:28:06.440 --> 00:28:09.519
dinner party. As for me three point one four one

479
00:28:09.640 --> 00:28:12.920
five nines about it, of course, as well as pie day.

480
00:28:13.200 --> 00:28:16.519
March fourteen is also the birthday of the great professor

481
00:28:16.559 --> 00:28:20.440
doctor Albert Einstein. And joining us now for the risk

482
00:28:20.480 --> 00:28:22.839
of our tour of the March night skies. You're seeing

483
00:28:22.839 --> 00:28:27.079
your science writer and Sky and Telescot Magazine contributor Jonathan Nally.

484
00:28:26.839 --> 00:28:29.480
Today, Stuart Yet March night Sky. Now, we normally start

485
00:28:29.519 --> 00:28:31.400
our tour of the night sky by looking to the shout,

486
00:28:31.400 --> 00:28:33.079
but this time I thought we'd start with the new

487
00:28:33.160 --> 00:28:35.000
to the north, at least as we see it from

488
00:28:35.000 --> 00:28:36.960
down here where I live within the mid mid latitudes

489
00:28:36.960 --> 00:28:38.559
of the Southern Hemisphere. So as I look to the

490
00:28:38.599 --> 00:28:41.279
north during March evenings, low down in the northern sky,

491
00:28:41.359 --> 00:28:44.440
we've got four constellations of the zodiac. We've got Taurus, Gemini,

492
00:28:44.680 --> 00:28:47.960
Cancer and Leo. Famous constellations Cancer and Leo. They're a

493
00:28:48.000 --> 00:28:50.400
bit bare for the Naked Eye star games, there's not

494
00:28:50.400 --> 00:28:52.599
a lot to see. But Gemini and Taurus, these ones

495
00:28:52.599 --> 00:28:55.720
are really really good, great constellations primarily because they've got

496
00:28:55.720 --> 00:28:57.960
a couple of really really good while his Taurus had

497
00:28:58.000 --> 00:28:59.960
a couple of really really good the starclofters in it.

498
00:29:00.079 --> 00:29:02.400
So in Taurus you've got one called the Hyades, which

499
00:29:02.440 --> 00:29:04.720
is a V shape or wedge shaped group is stars

500
00:29:04.799 --> 00:29:08.319
quite large, it's really quite noticeable. It stands out. And

501
00:29:08.319 --> 00:29:11.160
there's another one that's a little way away and it's

502
00:29:11.200 --> 00:29:13.599
smaller though quite stunning. It's called the Pleiades all the

503
00:29:13.640 --> 00:29:16.000
Seven Sisters, which we've spoken about many many times on

504
00:29:16.039 --> 00:29:18.519
the program. That's when I first mentioned the Hyades cluster.

505
00:29:18.759 --> 00:29:21.680
It has a fairly bright reddish, really dark reddish sort

506
00:29:21.720 --> 00:29:23.759
of star at its head, and that's the star called

507
00:29:23.759 --> 00:29:26.240
al Deboron or Aldi Barron or some people call it.

508
00:29:26.400 --> 00:29:29.240
That's in Taurus. In Gemini. Gemini also does have some

509
00:29:29.319 --> 00:29:31.480
nice star clusters, but you really need a para monoculars

510
00:29:31.519 --> 00:29:33.200
to get a good view of those at least and

511
00:29:33.279 --> 00:29:35.359
a telescopeia and better. But you can always tell the

512
00:29:35.359 --> 00:29:38.440
constellation Gemini because it has two bright stars quite close

513
00:29:38.480 --> 00:29:41.119
together and they're both pretty much the same brightness as well.

514
00:29:41.160 --> 00:29:43.799
One's called Castor and one is called Pollux, which is

515
00:29:44.119 --> 00:29:47.559
two bright stars close to get a similar brightness. Obviously

516
00:29:47.680 --> 00:29:50.400
Gemini the twins. So still in the north for us

517
00:29:50.400 --> 00:29:52.480
in the southern hemisphere, at least the higher up than

518
00:29:52.519 --> 00:29:55.720
those Zodier constellations, we've got the mighty Orion, which is

519
00:29:55.720 --> 00:29:57.599
one of the best knownab all the constellations. Of course,

520
00:29:57.599 --> 00:29:59.039
we talk about it all the time on the show.

521
00:29:59.119 --> 00:30:01.599
Grab the chance to see now during March, because a

522
00:30:01.640 --> 00:30:03.880
couple of months time it will have dropped below the

523
00:30:03.920 --> 00:30:06.359
western horizon and we won't see it again until the

524
00:30:06.440 --> 00:30:08.200
end of the year. This is the thing with constellations

525
00:30:08.240 --> 00:30:10.839
this season because for us at this time of year,

526
00:30:11.039 --> 00:30:14.279
when it's nighttime, we're looking in one particular direction in space,

527
00:30:14.440 --> 00:30:16.839
out into space. Right six months from now we'll be

528
00:30:16.839 --> 00:30:18.559
around on the other side of the sun and the

529
00:30:18.640 --> 00:30:20.960
night time there will be looking in the opposite direction

530
00:30:21.160 --> 00:30:24.480
out into space. So as months go by, constellations drop

531
00:30:24.519 --> 00:30:26.200
over the western horizon, they come up in the east,

532
00:30:26.240 --> 00:30:29.000
and they just go this repeating pattern every year, every year.

533
00:30:29.039 --> 00:30:31.319
Every year, so Orion and the sort of ones crowd

534
00:30:31.359 --> 00:30:33.640
the chance to see. And now before the weather we're

535
00:30:33.640 --> 00:30:35.359
heading into winter down here in the South, so before

536
00:30:35.400 --> 00:30:37.279
the weather gets bad and then we get lots of

537
00:30:37.279 --> 00:30:39.920
cloudy weather and you can't see anything. So yeah, another words,

538
00:30:39.920 --> 00:30:41.200
to look at it now, because it's going to be

539
00:30:41.200 --> 00:30:43.880
going a couple months time now high overhead for us

540
00:30:43.920 --> 00:30:46.279
in the South. At least we've got the two brighter

541
00:30:46.359 --> 00:30:50.079
stars in the night sky. We've got Serious and Canopus.

542
00:30:50.319 --> 00:30:52.920
Serious is actually a binary star system made up of

543
00:30:52.960 --> 00:30:55.240
two stars, one a really bright one and the other

544
00:30:55.279 --> 00:30:57.599
one you can't see. So the larger of its two

545
00:30:57.640 --> 00:31:00.480
stars is about twice as massive as the sun, very bright,

546
00:31:00.559 --> 00:31:03.359
and the other one is a very tiny, unseen white

547
00:31:03.400 --> 00:31:06.039
dwarf star. You've got no over seeing it. It's really small,

548
00:31:06.200 --> 00:31:09.079
very close to its primary star, and just gets drowned

549
00:31:09.079 --> 00:31:11.799
out by the light of the main star in Serious. Now,

550
00:31:11.839 --> 00:31:14.359
Serious is about twice as bright as Canopus as we

551
00:31:14.400 --> 00:31:17.519
see them in the night sky, even though Canopus itself,

552
00:31:17.880 --> 00:31:19.960
the second brightest star in the night sky, is four

553
00:31:20.079 --> 00:31:24.279
times as massive as Serious, and intrinsically it's much much

554
00:31:24.319 --> 00:31:27.079
and brighter. It's a brighter star, but it seems dinner

555
00:31:27.119 --> 00:31:29.720
because it's a lot further away. Canopus is three hundred

556
00:31:29.759 --> 00:31:33.160
and ten light years from Earth, where Serious is very nearby,

557
00:31:33.240 --> 00:31:35.480
it only about eight and a half light years. So

558
00:31:35.559 --> 00:31:38.160
if you put Sirius at the same distance as Canopus,

559
00:31:38.200 --> 00:31:40.720
it'd be it'll be a nothing sort of star, and

560
00:31:40.799 --> 00:31:43.160
Canopus would be the brightest. So this is the thing

561
00:31:43.200 --> 00:31:44.640
you need to sort of remember when you're looking up

562
00:31:44.640 --> 00:31:46.119
there in the night sky and see all these dark

563
00:31:46.160 --> 00:31:48.039
and some are bright and some are dim. Some are

564
00:31:48.039 --> 00:31:50.880
bright because they are intrinsically bright, but sometimes it's just

565
00:31:50.880 --> 00:31:54.119
because they're close. And stars that are dim may be

566
00:31:54.480 --> 00:31:57.119
actually really bright stars, but they're just a long way away.

567
00:31:57.200 --> 00:32:00.200
That's the way things go. Now, sweeping south along the

568
00:32:00.240 --> 00:32:02.240
way past Serious and format has become to the far

569
00:32:02.400 --> 00:32:06.440
southern constellations. That does the shoven Cross or Crux or Crooks,

570
00:32:06.440 --> 00:32:09.440
so I'm told it should be properly pronounced in Latin.

571
00:32:09.680 --> 00:32:11.799
And another one called Karna, which is a really great

572
00:32:12.079 --> 00:32:14.279
constellation to see down there, lots of great stuff to

573
00:32:14.279 --> 00:32:17.400
see whether pair of binoculars. The Southern Cross is hard

574
00:32:17.440 --> 00:32:19.279
to see at the beginning of the year, of the

575
00:32:19.359 --> 00:32:20.559
end of the year. In the beginning of the year,

576
00:32:20.640 --> 00:32:23.359
but by by March it's actually quite easy to see.

577
00:32:23.440 --> 00:32:25.720
As the months go on and the Earth is rotating.

578
00:32:25.920 --> 00:32:28.160
The Southern Cross, which during the end of the year

579
00:32:28.200 --> 00:32:30.839
period is way down on the southern horizon and is

580
00:32:30.839 --> 00:32:34.079
often below the horizon for many stargazers. It's now up

581
00:32:34.079 --> 00:32:35.720
a bit higher, so you should be able to see

582
00:32:35.720 --> 00:32:38.559
it no matter what. Just remember that this time of

583
00:32:38.640 --> 00:32:41.400
year it's on its left hand side, sort of kite shape, right,

584
00:32:41.440 --> 00:32:43.599
So imagine a kite lying on its left hand side

585
00:32:43.759 --> 00:32:46.440
and probably about a further way up from the horizon.

586
00:32:46.680 --> 00:32:48.720
That's in the mid evening at least. Now, if you're

587
00:32:48.960 --> 00:32:51.400
up past midnight, then the Earth will have turned a

588
00:32:51.400 --> 00:32:53.599
bit more and therefore the Southern Cross full and risen

589
00:32:53.680 --> 00:32:55.720
the higher in the start, and you'll see it standing

590
00:32:56.039 --> 00:32:58.599
much higher and standing straight up, which is the way

591
00:32:58.640 --> 00:33:00.960
most people imagine it to be. Now, it's God of

592
00:33:00.960 --> 00:33:04.119
the planets what we've got. As the evening falls, as

593
00:33:04.119 --> 00:33:06.759
there's the darkness starts to fall. This month, only two

594
00:33:06.799 --> 00:33:09.519
of the planets visible to naked eye are up and visible,

595
00:33:09.559 --> 00:33:11.359
and one of them won't be visible for very long,

596
00:33:11.599 --> 00:33:13.720
and that one is Saturn. In the first week of

597
00:33:13.759 --> 00:33:15.559
the month, you might just be able to see it

598
00:33:15.599 --> 00:33:18.359
as a pin prick of light in the twilight glow

599
00:33:18.440 --> 00:33:20.599
out of the west after the sun has set. It

600
00:33:20.640 --> 00:33:23.119
will be in the orange blow of sunset after the

601
00:33:23.119 --> 00:33:25.160
sun has gone down, but by about the second week

602
00:33:25.200 --> 00:33:27.359
of March it will be lost in the Sun's glare.

603
00:33:27.400 --> 00:33:28.839
It's going to be around the other side of the

604
00:33:28.839 --> 00:33:30.759
Sun and we won't see it for a while. On

605
00:33:30.799 --> 00:33:34.000
the other hand, perfectly visible is Jupiter, the biggest planet

606
00:33:34.039 --> 00:33:36.119
in the Solar System, and you'll see this one about

607
00:33:36.160 --> 00:33:38.799
halfway up from the northern horizon for those where I

608
00:33:38.839 --> 00:33:41.359
live in mid latitudes in southern hemisphere, or it'll be

609
00:33:41.400 --> 00:33:43.359
to the south, directly to the south if you live

610
00:33:43.400 --> 00:33:45.880
in a country north of the equator. Now, Jupiter is

611
00:33:46.000 --> 00:33:48.480
pretty hard to miss because, apart from the Moon, it's

612
00:33:48.519 --> 00:33:50.480
the brightest thing in the late evening spy at this

613
00:33:50.559 --> 00:33:53.640
time of the year. Now I specify late evening sky

614
00:33:53.839 --> 00:33:55.920
because there is a third planet that's about to make

615
00:33:55.960 --> 00:33:58.599
its appearance, the one that's even brighter than Jupiter, and

616
00:33:58.599 --> 00:34:01.599
that's Venus. I mentioned Saturn before, and that it's going

617
00:34:01.599 --> 00:34:03.440
to be visible in the first week or so. The

618
00:34:03.680 --> 00:34:07.079
tiny pin prick of light in the western twilight glow,

619
00:34:07.279 --> 00:34:10.760
while as it disappears, Venus will appear up above the

620
00:34:10.800 --> 00:34:14.280
horizon in the west in that sort of glowing orange twilight,

621
00:34:14.519 --> 00:34:16.880
and it'll poka set up and it's spasically stay there

622
00:34:16.920 --> 00:34:19.559
hugging the horizon for all the rest of the month.

623
00:34:19.639 --> 00:34:21.559
So you should be able to see it because Venus

624
00:34:21.840 --> 00:34:24.559
is really big and bright, So even though it's in

625
00:34:24.599 --> 00:34:27.880
the glare, if you like of the twilight glow, because

626
00:34:27.880 --> 00:34:29.440
it's so big and right, you should be able to

627
00:34:29.480 --> 00:34:32.599
see it. Now, switching to the hours before sunrise, if

628
00:34:32.599 --> 00:34:35.519
you're up early or you're very very late, if you

629
00:34:35.559 --> 00:34:38.199
take a look into the dawn blow this time, before

630
00:34:38.239 --> 00:34:40.280
the sun peeps up over the horizon, you should see

631
00:34:40.320 --> 00:34:42.880
what looks like a small reddish star. Well, that's the

632
00:34:42.920 --> 00:34:45.719
planet Mars. And just like Venus, Mars is going to

633
00:34:45.800 --> 00:34:49.159
hug the eastern horizon before sunrise for the rest of

634
00:34:49.199 --> 00:34:51.559
this month, so you should be able to hear it

635
00:34:51.679 --> 00:34:54.199
roughly the same what astronomer is called altitude, but the

636
00:34:54.239 --> 00:34:56.760
distance above the horizon for most of the month. Now,

637
00:34:56.760 --> 00:34:59.159
if you keep watch, if you're up early at six

638
00:34:59.199 --> 00:35:02.239
o'clock or whatever early and you're watching the before the

639
00:35:02.239 --> 00:35:04.000
sun rise in the second half of the month, you'll

640
00:35:04.000 --> 00:35:06.159
see the planet Mercury. Day by day. It'll just see

641
00:35:06.400 --> 00:35:08.440
higher and higher and higher in the sky and it

642
00:35:08.480 --> 00:35:10.480
will be very easy to see. Mercury is one of

643
00:35:10.519 --> 00:35:13.119
those planets actually that very often is hard to see

644
00:35:13.159 --> 00:35:15.320
because of the way angles and things are working out

645
00:35:15.320 --> 00:35:18.079
between the Earth's orbit and planet's orbits, and what time

646
00:35:18.119 --> 00:35:20.880
of year it is and everything. Sometimes, even though Mercury

647
00:35:21.159 --> 00:35:24.199
might be at its greatest distance away from the Sun

648
00:35:24.320 --> 00:35:26.760
as seen in the sky, what astronomy is called elongation,

649
00:35:27.000 --> 00:35:29.079
and therefore you think of it's just fairly long way

650
00:35:29.079 --> 00:35:31.719
away from the Sun as seen in the sky, then

651
00:35:31.960 --> 00:35:34.159
it should be easy to see. But sometimes no, even

652
00:35:34.199 --> 00:35:36.039
though it could have a large elongation, it can be

653
00:35:36.280 --> 00:35:39.239
angled down to hoards or horizon, so it never rises

654
00:35:39.320 --> 00:35:41.719
very high those times. But this time it's going to

655
00:35:41.719 --> 00:35:43.360
come up sort of straight up, and it's going to

656
00:35:43.360 --> 00:35:45.159
be very very easy to see. The last thing for

657
00:35:45.280 --> 00:35:47.440
March Stuart is that, of course this time of the year,

658
00:35:47.519 --> 00:35:49.920
it's the equinops. So the equinops is going to happen

659
00:35:49.960 --> 00:35:52.239
on the twenty first of March or I am in

660
00:35:52.280 --> 00:35:54.480
Australia and some parts of the world will still be

661
00:35:54.519 --> 00:35:56.920
the twentieth of March, depending on what your time is

662
00:35:56.920 --> 00:35:59.159
on it is. The equinox, of course, is the time

663
00:35:59.199 --> 00:36:02.239
when the sun is rippy over the equator. In this instance,

664
00:36:02.320 --> 00:36:05.599
the siny is moving northwards over the equator, so that

665
00:36:05.760 --> 00:36:08.360
the northern hemisphere is moving towards summer and the southern

666
00:36:08.400 --> 00:36:11.800
hemisphere is moving towards winter. And the equinoxes the day

667
00:36:11.880 --> 00:36:14.800
when we get roughly equal hours of darkness and daylight.

668
00:36:14.840 --> 00:36:17.239
And of course we get two equinoxes, one when the

669
00:36:17.280 --> 00:36:19.880
SNY is moving towards the north over the equator and

670
00:36:20.000 --> 00:36:22.199
one six months later when it's moving out of the south.

671
00:36:22.360 --> 00:36:24.719
So this one in March crossing the southern hemisphere is

672
00:36:24.760 --> 00:36:26.960
indicates that winter's on the tway while they're friends in

673
00:36:27.000 --> 00:36:28.880
the north and they've got summer coming along and all

674
00:36:28.920 --> 00:36:30.840
their horrible snow and stuff is going to go away.

675
00:36:30.920 --> 00:36:33.039
And that's Stewart is the Blacker March.

676
00:36:33.039 --> 00:36:35.679
That senior science writer and Skyne tell Us atout the

677
00:36:35.679 --> 00:36:39.480
magazine contributed Jonathan Nelly and this Space.

678
00:36:39.199 --> 00:36:56.559
Time and that's the show for now.

679
00:36:57.119 --> 00:37:00.559
The Space Time is available every Monday Wednesday and through

680
00:37:00.679 --> 00:37:05.679
bytes dot com, SoundCloud, YouTube, your favorite podcast download provider

681
00:37:05.880 --> 00:37:09.480
and from space Time with Stuart Gary dot com. Space

682
00:37:09.559 --> 00:37:12.960
Time's also broadcast through the National Science Foundation, on Science

683
00:37:13.000 --> 00:37:16.760
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684
00:37:17.320 --> 00:37:19.679
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685
00:37:19.679 --> 00:37:23.360
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686
00:37:23.800 --> 00:37:27.000
or by becoming a Spacetime Patron, which gives you access

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to triple episode commercial free versions of the show, as

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well as lots of burnus audio content which doesn't go

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to wear, access to our exclusive Facebook group, and other rewards.

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Just go to space Time with Stuart Gary dot com

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for full details.

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00:37:41.559 --> 00:37:44.800
You've been listening to space Time with Stuart Gary. This

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00:37:44.880 --> 00:37:51.320
has been another quality podcast production from bytes dot com