Jan. 1, 2026

Stellar Spectacles: January's Night Sky Highlights

SpaceTime with Stuart Gary Gary - Series 29 Episode 1 In this episode of SpaceTime, we delve into extraordinary cosmic phenomena and the ongoing exploration of our solar system. Cosmic Matter Ejected at 20% the Speed of Light Astronomers have made a...

Show Notes
Transcript

SpaceTime with Stuart Gary Gary - Series 29 Episode 1
In this episode of SpaceTime, we delve into extraordinary cosmic phenomena and the ongoing exploration of our solar system.
Cosmic Matter Ejected at 20% the Speed of Light
Astronomers have made a groundbreaking observation of matter being ejected from a supermassive black hole at the center of the barred spiral galaxy NGC 3783, located 135 million light years away. This matter, propelled at an astonishing 20% the speed of light, challenges previously held notions about how such superluminal jets are powered. The findings suggest that a sudden change in the magnetic field, rather than radiation, may be responsible for this high-speed outburst, providing new insights into the mechanisms of black hole dynamics and their impact on galactic evolution.
Wind-Sculpted Landscapes on Mars
NASA's Perseverance Rover continues its exploration of Mars, focusing on megaripples—large sand formations shaped by wind. These megaripples, some reaching up to 2 meters in height, offer scientists a unique opportunity to study current Martian atmospheric processes. As the rover investigates the Honeyguide region, researchers hope to gain insights into the planet's wind patterns and surface chemistry, which will be crucial for future human missions to Mars.
Potential Ocean Beneath Uranus's Moon Ariel
New research suggests that Uranus's moon Ariel may harbor a vast subsurface ocean, potentially more than 170 kilometers deep. This discovery, reported in the journal Icarus, highlights Ariel's unique geological features and raises questions about its past interior structure and orbital dynamics. The study indicates that understanding Ariel's ocean could provide crucial context for the moon's surface fractures and cryovolcanic activity, emphasizing the need for future missions to the Uranian system to confirm these findings.
www.spacetimewithstuartgary.com
✍️ Episode References
Astronomy and Astrophysics
Icarus
NASA Reports
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(00:00:00) This is Space Time Series 29, Episode 1 for broadcast on 2 January 2026
(00:00:47) Cosmic matter ejected from supermassive black hole
(00:12:30) Perseverance Rover studies wind-sculpted megaripples on Mars
(00:20:10) Evidence of a subsurface ocean beneath Uranus's moon Ariel
(00:25:00) Skywatch: January night sky highlights and celestial events

The Astronomy, Space, Technology & Science News Podcast.

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This is Spacetime Series twenty nine, Episode one, for broadcast

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on the second of January twenty twenty six. Coming up

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on space Time, cosmic matter spotted traveling at twenty percent

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the speed of light, studying wind sculpted landscapes on the

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red planet Mars, and could there be a vastation under

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the surface of Uranus's moon Ariel. 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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Astronomers have observed a sudden outburst of matter near a

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super massive black hole, shooting out into deep space at

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some twenty percent the speed of light. The findings reported

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in the journal Astronomy in Astrophysics a demonstration a new

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way of powering these superluminal jets. Astronomers were studying the

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super massive black hole at the center of NGC thirty

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seven eighty three, a barred spiral galaxy some one hundred

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and thirty five million light years away the constellation Centaurus.

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During a ten day observational run primarily using NASA's Chrism

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space telescope. Astronomers witness powerful outbursts of matter being ejected.

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Now they often find that these outbursts are powered by

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strong radiation, But this time the most likely cause isn't radiation,

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but a sudden change in the magnetic field, similar to

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bursts on the Sun caused by solar flares. While super

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massive black holes are known to flicker and X rays,

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this is the first time astronomers have clearly seen a

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high speed ejection accelerated during an X ray burst. During

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this ten day period, scientists saw variations in X ray

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brightness and intensity, especially in the softer X ray bands. Now,

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these changes, including the outbursts that lasted for three days,

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aren't un usual for super massive black holes. However, what

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makes this event so unique is the simple tennis ejection

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of gas from the accretion disc of swirling matter orbiting

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the black hole. This gas was expelled at incredibly high speeds,

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reaching some sixty thousand kilomets per second that's twenty percent

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the speed of light. The gas appear to originate from

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a region at a distance roughly fifty times the size

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of the black hole itself. In this turbulent region, gravity

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and magnetic forces interact in extreme ways. The authors believe

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the ejection was caused by a process called magnetic reconnection.

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The sudden reconfiguration of magnetic fields, releasing huge amounts of

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energy in the process. The Steadies lead author Lay Ego

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from the Netherlands Institute of Space Research says these observations

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are providing a unique opportunity to study the launch mechanism

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for ultrafast outbursts. The data suggested the acceleration of the

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outflow is being driven by magnetic forces, similar to chronal

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mass ejection from the Sun.

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Now.

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Coronal mass ejection on the Sun happens when larch blobs

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of hot plasma and magnetic field are hurled into space

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during a solar flare event, and a super massive black

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hole can do the same, only the eruptions that tens

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of billions of times more powerful, dwarfing anything everything blasting

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out from our sun doing. Colleagues propose that the observed

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black hole event, just like its solar counterpart, is being

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fueled by sudden bursts of magnetic energy, but that contradicts

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the hypothesis that black holes expel matter through intense radiation

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or extreme heat. The results therefore often new insights into

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how black holes not only pull matter in and under

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the right conditions, can also shoot it back out again

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into space. The process has been dubbed feedback, and it

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may play a key role in how galaxies grow and

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change over time, influencing the stars and gas around the

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black hole and helping shape the universe as we see

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it today. This is space time still to come studying

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the wind sculpted landscapes of the red planet Mars, and

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could there be a vast ocean under the surface of

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Uranus' moon Ariel. All that and more still to come

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on space time. While much of NASA's Mars Perseverance Rover's

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work focuses on ancient rocks that record the red planet's

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long lost rivers and lakes, mega ripples are offering a

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rare opportunity to examine processes which are still shaping the

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Martian surface today. Mega ripples are sand ripples, some up

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to two meters tall, that are mainly built and modified

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by wind. However, when water in the atmosphere interacts with

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dust on the ripple surface, a salty, dusty crust can

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often form, and when this happens, it's much harder for

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the wind to move or reshape the mega ripple. As such,

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mega ripples on Mars are largely considered inactive, standing as

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records of past wind regimes and atmospheric water interactions. Over time. However,

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some have shown signs of movement, and it's possible that

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periods of high wind speeds may erode or even reactivate

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these deposits. Again. Despite within Martian atmosphere today, which is

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just two percent that of Earth's atmosphere density, wind remains

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one of the main drivers of change on the Martian surface,

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eroding local bedrock into sand sized grains and transporting these

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grains across the ripple field. As a result, Mega Ripple

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studies and help scientists better understand how wind reshapes the

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Martian surface, how it changes the planet's recent history, and

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in the process, it will help scientists plan for future

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human missions to the Red planet, because the chemistry and

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cohesion of Martian soils will influence everything that people do

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on Mars, from mobility through the resource extraction. Following the

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successful investigation of the does the inactive mega ripple at

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Kurla Guna, the cas sized Perseverance Rover, which is traveling

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along the rim of Jezrot Crater, has now begun exploring

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a new, more expansive field of mega ripples known as Honeyguide.

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This region boasts some of the largest mega ripples ever

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seen along the rover's journey so far. That makes it

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an ideal location for a comprehensive study of these features.

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The mega ripples at Honeyguide are larger and extend further,

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and have sharply defined crests with more uniform orientation compared

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to those at Kerla Guna. The consistent orientation of the

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mega ripples that Honeyguide suggests that the winds in this

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area have been blowing predominantly from the same direction, that's

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north to south, for a long, long period of time.

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At honey Guide, Perseverance has been studying the Hazy View

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mega ripple, where more than fifty observations have now been taken,

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looking for grain movement, signs of early morning frost, and

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for changes in mineralogy from crest to trough. The investigation

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of the Hazy View bed form builds the directly on

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the results from Kerlaguna and represents the most detailed study

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yet of these intriguing wind form deposits this space time

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still to come. Could there be a vast ocean deep

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under the surface of Uranus's moon Ariel and planet earth

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richest Perihelian serious, the brightest star in the night sky.

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The missing constellation of Argo Navis and the Quadranted's meteor

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showers are among the celestial highlights of the January night

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skies on SkyWatch. There's growing evidence suggesting that a vast

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subsurface ocean could be lurking beneath the icy surface of

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Uranus' moon Ariel. The findings reported in the journal Icarus,

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looks at the possible evolution of this ocean, finding that

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it may once have been more than one hundred and

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seventy kilometers deep. Now, by comparison, Earth's largest ocean, the

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Pacific average, is just four kilometers in depth. One of

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the studies authors, Alex Padder from the Planetary Science Institute,

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says Ariel is unique in terms of icy moons. It's

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the brightest and second closest moon to Uranus, and at

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just one one hundred and fifty nine kilometers in diameter,

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it's the fourth largest moon in the entire Uranian System.

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From the little astronomers can see, it has some very

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old geological features like craters, which are right next to

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some very young features like smooth terrain of the type

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possibly created by cryovolcanism. Ariel has fractures, ridges and grabon.

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That's crust that's dropped lower than its surroundings, and it

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has these its scales larger than almost anything anywhere else

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in our solar system. It's this dramatic landscape that's prompted

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the study. The authors want to understand Ariel's past interior

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structure as well as its orbit eccentricity, that is, how

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much the Moon's orbit deviates from s circular, which would

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help define how features on Arial's surface have evolved today.

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Both characteristics can contribute to how much stress can be

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applied to the surface, causing it the fracture under the

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push and pull gravity that's exerted on the small Moon

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as it orbits around its ice giant host. To work

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out what's going on, the authors first mapped out the

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large structures which we're able to see on the Moon's surface.

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They then use a computer program the model the tidal

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stresses on the surface, which result from the distortion of

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ariol from a soccer ball shaped object a slightly more

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elongated rugby league or gridiron shaped ball, which then moves

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back to around soccer ball shape and back to an

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elongated shape as it moves closer and further from Urinus

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during its orbit around the planet. Platov says, by combining

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the model with what can be seen on the surface,

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Heed his colleagues were able to make some inferences about

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Ario's past eccentricity and how thick the ocean beneath the

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surface must have been. They found that in the past,

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Ariol needed to have an eccentricity of about zero point

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zero four. That's about forty times higher than its current value.

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While zero point zero four may not sound very dramatic,

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eccentricity can strengthen the effects of tidal stresses, and Ariel's

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orbit would have been four times more eccentric than that

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of Jupiter's moon Europa, which is racked by tidal forces

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pushing and pulling on it, creating its cracked and broken surface.

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Patov says, in order to create these fractures, the body

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has to have either really thin ice on a really

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big ocean, or a higher eccentricity and a smaller ocean,

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but either way, one still needs an ocean to create

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the sorts of fractures seen on ariel surface. These new

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findings represent the second in a series of studies investigating

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the moons of Uranus. Back in twenty twenty four, the

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same set of authors published a paper on Miranda with

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similar results. Of course, the problem is astronomers have only

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seen the southern hemispheres of both Aril and Miranda. Ultimately,

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astronomers will need to send a mission there studying the

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Urinus system in order to find out what's really going on.

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This is space time, and time that to turn our

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eyes to the skies and check out the celestious sphere

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for January on SkyWatch. January is the first month of

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the year in the Julian Angagorian calendars. The name originates

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in the Latin word for door. That's because January is

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the door to the new year and an opening to

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new beginnings. The month is conventionally thought of as being

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named after Janus, the mythical Roman god of beginnings in transitions,

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but according to the ancient Roman Farmer's Almanac, it was

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actually Juno, who was the traditional god of January. Of course,

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from an astronomical point of view, January marks Earth's closest

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orbital position to the Sun perihelion, which occurs of two

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weeks after the descent of solstice. Planets, including the Earth,

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don't orbit the Sun in perfect circles, but rather in

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ever changing elliptical orbits. The shape of these orbits vary

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due to gravitational influences from other planetary objects, and in

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Earth's case, that especially includes the Moon, which is almost

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massive enough to be considered a binary partner. So over

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a roughly one hundred thousand year cycle, Earth's orbit changes

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in shape from almost circular to far more elliptical. This

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difference is known as eccentricity, and the nearest point in

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Earth's orbit around the Sun is called perihelium. This year,

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perihelium will occur on Sunday, the fourth of January, at

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four fifteen in the morning Australian Eastern daylight time. That's

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when the Earth will be just one hundred and forty

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seven million, ninety nine thousand and eight hundred and ninety

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four kilometers from the Sun. That's a quarter past twelve

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in the afternoon of Saturday, January the third US Eastern

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Standard time, and five point fifteen in the afternoon of

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January the third Gretitch meantime. Around six months later, and

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about two weeks after the June solstice, Earth will be

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at its furthest orbital position from the Sun, a location

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known as Appelian. Okay, let's start our tour of the

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January night sky by looking to the northeast, right next

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to the constellation of Ryan, where you'll see the brightest

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star in the night sky, the Dog Star Serious, so

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called because it's the brightest star at the constellation Canis Major,

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the Big Dog. The name Sirius actually meets scorching or brilliant,

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a clear reference to its spectacular brightness in the sky.

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As well as being one of the nearest stars to

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the Sun at just eight point seven light years, it's

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also intrinsically bright and almost twice as bright as the

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second brightest star in the night skies, Canopus. A light

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year is about ten trillion kilometers, the distance a photon

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can travel in a year at three hundred thousand kilometers

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per second, the speed of light in a vacuum, and

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the ultimate speed limit of the universe. Sirius is the

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fifth closest start of the Sun, and it's gradually moving

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closer to the Soul system, so it will steadily increase

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in brightness over the next sixty thousand years, after which

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time it will begin moving away again, and it will

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gradually become fainter and fainter, but it will still continue

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to be the brightest star in Earth's night sky for

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at least the next one hundred and ten thousand years.

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Sirius is a binary star system comprising a spectro type

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A main sequence white star called Serious A, and a

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small white dwarf companion, Serious B, which orbits between eight

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point two and thirty one point five astronomical units away

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from the primary star. An astronomical unit is the average

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distance between the Earth and the Sun, about one hundred

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and fifty million kilometers. Main Sequence stars are those undergoing

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hydrogen fusion into heal him in their core. Astronomers describe

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stars in terms of spectro types, a classification system based

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on temperature and characteristics. The hottest, most massive, and most

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luminous stars are not a spectro type of blue stars.

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They follow by spectual type B blue white stars and

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spectrotype A white stars, spectual type F whitish yellow stars,

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specual type G yellow stars. That's where our Sun fits

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in spectrotype K orange stars, and the coolest and least

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massive stars known are spectrotype M red stars. Each spectral

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classification can also be subdivided using a numeric digit to

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represent temperature, with zero being the hottest and nine the coolest,

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and a Roman numeral to represent luminosity. Now put all

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that together, and our Sun becomes a G two v

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G two five yellow dwarf star. Also included in the

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spectral classification system are spectrotypes LT and Y, which are

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assigned to feldstars known as brown dwarves, some of which

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were born as spectual type M red stars but became

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brown dwarves after losing some of their mass. Brown dwarves

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fit into a category between the largest planets, which are

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about thirteen times the mass of Jupiter, and the smallest stars,

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those spectro type M red dwarfs we talked about before,

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which are about seventy five to eighty times the mass

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of Jupiter or around zero point zero eight solar masses.

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Brown dwarves don't have enough mass to build up the

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sorts of temperatures and pressures in their cores needed to

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trigger the nuclear fusion process which makes stars like our

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sun shine. Serious A has at least twice the mass

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of the Sun and is about twenty five times more luminous.

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The serious binary system is between two hundred three hundred

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million years old, quite young by astronomical standards, and it

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originally consisted of two bright spectral type A white stars.

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The more massive of these two stars, Serious B, consumed

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its resources and became a red giant before shedding off

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its outer layers and collapsing into its current state as

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a white dwarf around one hundred and twenty million years ago.

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A white dwarf is the stolar corpse of a Sun

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like star, having used up its nuclear fuel supply of

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fusing hydrogen to helium and its core, it expands into

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a red giant as it fuses helie him into carbon

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and oxygen. Now biggest stars confused progressively heavier and heavier elements,

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but lo maas stars like the Sun simply aren't big

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enough to fuse carbon and oxygen into heavier elements, and

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so they turn off their outer Gas's envelope separates and

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floats off into space as a spectacular object called a

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planetary nebula. What's left behind is a super dense, white

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hot stellar core about the size of the Earth, called

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a white dwarf, which will slowly cool down over the

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eons of time. Our Sun will become a white dwarf

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in about seven billion years from now five thousand years ago.

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The ancient Egyptians looked at Sirius and they saw it

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as the god of Nebis, lord of the underworld, who

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had the head of a dog, and who invented him

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balming the funeral rites, and who guided one through the

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underworld to judgment, where he attended the scales during the

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weighing of the heart to determine one's fate in the afterlife.

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And Nubis was later replaced in Egyptian mythology by Assiris

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as the lord of the underworld, and Sirius became the

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goddess Isis. By carefully watching Sirius's movements across the sky,

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the ancient Egyptians determined that it would be visible every

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night for two hundred and ninety five and a quarter nights,

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followed by seventy nights of absence, and this allowed them

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to determine that a year was three hundred and sixty

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five and a quarter days long. Their calculations were accurate

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to within eleven minutes. The hell call rising of Sirius

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also marked the annual flooding of the river Nayle in

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ancient Egypt, and the hot, sultry dog days of summer

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for the ancient Greeks. In Greek mythology, Sirius was the

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dog star and the canine companion of Orian, the hunter.

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Helly call Rising refers to the first time of the

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year when it star becomes visible above the eastern horizon

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for a brief moment just before sunrise. It's been claimed

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that the Dogon people in Mali and Western Africa have

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ancient stories describing the fifty orbital period of Sirius and

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its companion White Dwarf, which pre date the White Dwarf's

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discovery by modern astronomers. Also claimed that these legends were

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handed to the Dogon people by ancient aquatic space travelers

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who told them of the third star accompanying Serius A

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and B. However, a report in the journal Current Anthropology

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raised serious doubts about whether the stars referred to by

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the Dogon people were in fact serious A and its

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White Dwarf companion. That's because Senior Dogon claimed the story

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actually refers to a different grouping of stars. Also, other

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researchers have pointed out that the Dogon could have heard

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about the discovery of Sirius's companion and then simply incorporated

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into their mythology. In eighteen ninety three, when a French

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expedition arrived in Central West Africa to observe in April

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sixteen total eclipse, and were overheard discussing the discovery. Looking

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due north just above the horizon this time of year,

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and you'll see the bright yellowish star Capella, the brightest star,

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and the constellation Riga the charioteer. Capella is the Latin

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term for a small female gar got. The star's alternative

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name is Capra, which is more commonly used in classical times.

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Although it appears to be a single start of the

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unaided eye, Capeller is actually a system of four stars

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in two binary pairs. The first pair comprises two bright

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yellow giant stars, both of which were around two and

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a half times the mass of the Sun. Having exhausted

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their core hydrogen supplies, both stars have cooled and expanded

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out to become giants, moving off the main sequence. Designated

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Capella AA and Capeller AB. They're in a very tight

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circular orbit, some zero point seven to six astronomical units apart,

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orbiting each other every one hundred and four earth days.

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Capella AA is the cooler and more luminous of the two,

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with some seventy eight times the luminosity and twelve times

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the radius of the Sun. Known as an aging red clumpstar,

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Capeller AA is fusing helium into carbon and oxygen in

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its core. Capella AB is a slightly smaller but hotter

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subgiant about seventy three times is luminous and almost nine

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times the radius of the Sun, and it's in the

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process of expanding out to become a red giant. The

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Capella system is one of the brightest sources of X

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rays in the sky, thought to come primarily from the

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corona of the more massive giant. The second pair of

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stars and Capella are located about ten thousand astronomical units

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from the first pair. They consist of two faint, small,

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relatively cool spectral type M main sequence red dwarf stars.

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The two red dwarfs have been designated Capella H and

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Capella L. Now almost directly overhead this time of year,

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a position in the sky known as Zenith, we find Canopus,

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the second brightest star in the night sky after Sirius,

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located some three hundred and thirteen light years away in

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the constellation Careen. Of the keel. Canopus looks incredibly bright

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because it is huge. It's a giant spiritual type, a

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white star with some ten times the mass, seventy one

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times the diameter, and ten thousand times the luminosity of

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the sun. Canopus is another bright X ray source, also

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most likely produced by its corona, magnetically headed to several

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million kelvin. The temperature is also likely to be stimulated

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by fast rotation combined with strong internal convection currents percolating

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through the stars out of layers. No star in our

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night sky closer than Canopus is more luminous than it,

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and it's been the brightest star on earth night sky

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during three different epochs over the past four million years.

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Other stars appear brighter only during relatively temporary periods during

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which they're passing the Solar System at much closer distances

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than Canopus. About ninety thousand years ago, serious move close

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enough that it appeared to be brighter in our night

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sky than Canopus, and as we mentioned earlier, that'll remain

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the case for another two hundred and ten thousand years,

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But in four hundred and eighty thousand years from now,

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Canopus will once again be the brightest star in the

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night sky, and it will remain so for a period

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of about five hundred and ten thousand years. In Greek mythology,

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Canopis was a helmsman and the navigator for the fleet

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of Menelaus, king of Sparta, which was sailing back from

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the Battle of Troy. Canopus is said to have died

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when the fleet arrived to the port of Alexandria in Egypt,

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and so a star which was visible on the horizon

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was named in his honor. Now, as we said, it's

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the brightest star in the constellation Carina, which represents the

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keel of the boat Argo, used by Jason the Argonauts

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in their quest for the Golden Fleece, located nearby other

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vessels sails represented by the constellation Vila, and the roof

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00:23:35.160 --> 00:23:37.480
of the Bert's rear cabin or poop deck, which is

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represented by the constellation Pappis. Combined Karina, Villa and Pappas

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used to form the constellation Argo Navis, representing the ship

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Argo skimming along the river of the Milky Way. But

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moderday astronomers considered the constellation simply too big, as it

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was twenty eight percent larger and the next largest constellation

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