Dec. 5, 2025

Lightning Strikes Mars: The First Detection of Electrical Discharges and NASA's New Look at Comet 3I Atlas

Show Notes
Transcript

In this episode of SpaceTime, we explore groundbreaking discoveries and intriguing phenomena from Mars to the depths of space.
Lightning Strikes on Mars: A Historic Discovery
NASA's Perseverance Rover has made a remarkable find by detecting lightning in the Martian atmosphere for the first time. Recorded within two dust devils in Jezero Crater, the rover's Supercam microphone captured electromagnetic and acoustic signals indicative of electrical discharges. This discovery not only confirms long-held theories about Martian electrical activity but also reveals significant implications for the planet's atmospheric chemistry and potential hazards for future missions.
NASA's Observations of Interstellar Comet 3I Atlas
Following the European Space Agency's observations, NASA has released stunning images of interstellar comet 3I Atlas. As the comet passed close to Mars, NASA's MAVEN and Mars Reconnaissance Orbiter provided crucial data on its trajectory and chemical composition. These insights are helping astronomers piece together the comet's journey and origins, revealing potential clues about water in other star systems.
Moss in Space: Resilience Against the Void
A new study has shown that moss can survive the harsh conditions of space for up to 15 years. Researchers sent moss spores to the International Space Station, where they thrived despite exposure to the vacuum and extreme temperatures. This remarkable resilience could have implications for understanding life's potential to endure in extreme environments beyond Earth.
Skywatch: December Highlights
As the December solstice approaches, we take a look at the night sky's highlights, including the Geminids meteor shower and the ticking time bomb of Eta Carina. We also discuss the significance of the December solstice and the celestial events that define this time of year.
www.spacetimewithstuartgary.com
✍️ Episode References
Journal of Nature
NASA Reports
Journal of Eye Science
Become a supporter of this podcast: https://www.spreaker.com/podcast/spacetime-your-guide-to-space-astronomy--2458531/support.
(00:00:00) NASA's Mars Perseverance Rover has captured evidence of electrical discharges
(00:03:47) NASA publishes its own observations of the Interstellar Comet 3I Atlas
(00:07:26) Moss spores survive exposure to vacuum of space for up to 15 years
(00:09:40) The December solstice marks the beginning of winter in both hemispheres
(00:11:54) Axial precession causes a slow and continuous change in Earth's rotational axis
(00:15:11) Astronomers describe stars in terms of spectral types based on temperature and characteristics
(00:19:04) Two blue stars nearing end of their lives before exploding massive core collapse supernovae
(00:24:23) Just above the horizon is the constellation of Orion the Hunter
(00:34:04) Canopus talks about the effect of the Moon on stargazing
(00:37:03) The Southern Cross starts near the celestial equator and wanders far south
(00:39:06) There are two star clusters that we speak about quite often on the show
(00:41:50) The only planet that's up in the early evening is Saturn

The Astronomy, Space, Technology & Science News Podcast.

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This is Spacetime Series twenty eight, episode one hundred and

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forty three for broadcasts on the fifth of December twenty

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twenty five. Coming up on Space Time, lightning detected on

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Mars for the first time, NASA's new images of interstellar

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Comet three I Atlas, and scientists discover that moss can

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survive in the vacuum of space. All that and more

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coming up on space Time.

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Welcome to space Time With Stuart.

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Gary, NASA's Mars Perseverance rover has captured evidence of electrical discharges,

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that is, lightning in the red planet's atmosphere. The findings,

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reported in the journal Nature, were recorded in two dust

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devil whirlwinds. Inside Jests wrote Crater on Mars, winds occasionally

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stir up fine dust, and it was at the center

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of two of these dust devils that the six world

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car sized Rovers supercam microphone recorded some especially strong signals.

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Analysis showed there were electromagnetic and acoustic signatures of electric

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disccharges comparable to the small static electricity shocks that can

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be experienced on Earth when touching a door handle in

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dry weather. Although long theorized, this is the first confirmation

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of the existence of electrical discharges in the Martian atmosphere.

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The phenomena can be explained by friction between tiny dust particles.

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They become charged with electrons, then release their charges in

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the form of electric arcs a few centimeters long, accompanied

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by a loud, audible shock wave. On Earth, that's well

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known that dust particles can become electrically charged, especially in

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desert regions, although this rarely results in actual discharges. But

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on Mars, the thin atmosphere, mostly made up of carbon

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dioxide makes this phenomenon much more likely to occur. See

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the amount of charge needed to form sparks is much

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lower than on Earth. The discovery of these electrical discharges

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profoundly changes sciences understanding of Martian atmospheric chemistry. These phenomenas

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show that the Martian atmosphere can reach significant levels of charge,

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speed up the formation of highly oxidizing compounds, and these

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substances can destroy organic molecules on the surface as well

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as numerous atmospheric compounds, thereby profoundly upsetting the photochemical balance

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of the atmosphere. The discovery could or explain the surprisingly

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rapid disappearance of methane on Mars, which has now been

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a subject of scientific debate for several years. The electrical

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charges required for these discharges are likely to affect the

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transportation of dust on Mars, thus playing a central role

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in Martian climate, the dynamics of which are still largely unknown.

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Of course, they also pose a risk to electronic equipment

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on current missions to the Red planet's surface, and they

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could also constitute a danger for future man missions to Mars.

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The microphone on the supercame instrument aboard Perseverance was first

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activated on Mars in twenty twenty one, the day after

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the rover landed on the Red planet. Switched on every day.

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It's now collected over thirty hours of sounds from the

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Red planet, the wind blowing the nose of the blades

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of the Ingenuity helicopter, and now some fifty electrical discharges.

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This is space time still to come. NASA's new images

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of interstellar Comet three I atlas, and a new study

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has shown that mass can survive the deadly vacuum of

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space for up to fifteen years. All that and more

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still to come on space time Hot on the hills

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of the European Space Agency's observations of the interstellar Comet

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three I outlas. NASAREUS published its own observations pieces. Observations

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using its Exo Mars Trace Gas orbiter improved the comet's

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predicted location by a factor of ten, capturing the alien

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visitor as the comet passed relatively close to Mars, approaching

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to about twenty nine million kilometers of the red planet

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on October. The third EXO Mars got about ten times

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close to three Our outlas than telescopes on Earth and

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observe the comet from a new viewing angle. The triangulation

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of this stata, combined with data from Earth, helped make

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the comet's predicted path much more accurate. It also helped

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put an end to all those wild claims that three

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are outlas maybe an alien spacecraft. NASA is Mayven. The

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Mars Atmospheric and Volatile Evolution Orbiter also monitor the comet

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for ten days as it slipped behind the Sun and

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out of view of the Earth. Mayven observed three Our

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outlas in ultraviolet light, exposing the glow of hydrogen silently

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pouring off the comet's icy surface. These data helping astronomers

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uncover new clues about the comets hidden chemistry, Hence about

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ancient water and other star systems, and even the ratio

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of hydrogen to deteryrium could reveal where this vagabond traveler

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was born, long before it was spotted in our solar system.

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Last July, as well as Maven, NASA also turned the

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Mars Reconnaissance orbited towards three I Atlas, capturing one of

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the closest images of the comet. Yet Meanwhile, down on

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the Martian surface, Perseverance rover also grabbed a faint glimpse

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of the comet from its position on the rim of

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Jezro Crater, and it doesn't end there. NASAs Stereo spacecraft

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captured images of the comet between September the eleventh and

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October the two and the joint NASA ISA Sooher spacecraft

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observed the comet from October fifteenth to the twenty sixth.

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Images from NASA's Punch mission, which launched earlier this year,

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revealed the comet's tail during its observations between September the

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twentieth and October the third. NASA's Psyche and Lucy missions

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currently on their respective outbound journeys to study various asteroid

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targets further out in the Solar system were also able

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to observe three I atlas. On September the eighth and ninth,

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PSAKI acquired four observations of the comet over eight hours

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from the distance of fifty three million kilometers away, and

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these images will further help scientists refine the comet's dejectory. Then,

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on September sixteenth, Lucy took a series of images from

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three hundred and eighty six million kilometers distant. Stacking all

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these images together provides details on the comet's coma and

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tail back. In August, both the web and spheric telescopes

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also captured imagery. Comet three I outlets will fly closest

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to the Earth around decemn the nineteenth. That's when it

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will pass at a distance of two hundred and seventy

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four million kilometers, which is still almost twice the distance

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between the Earth and the Sun. Needless to say, astronomers

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will continue to observe the comet as it continues its

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journey through our solar system, passing the orbit of Jupiter

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in early twenty twenty six, traveling at some two hundred

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and fifty thousand kilometers an hour before finally vanishing back

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into interstellar space, never to return. This is space time

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still to come. A new study has shown that mosc

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can survive the deadly vacu of space for up to

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fifteen years, and the December solstice, the ticking time bumb

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of Edacarina and the rock comet Phaeton are among the

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harlots of the December night skies on SkyWatch. A new

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study has shown that moss could survive in the deadly

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vacuum of space for up to fifteen years. The findings,

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reported in the journal Ice Science, are based on moss

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sports samples sent to the International Space Station, where they

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survived exposure to the vacuum of space for up to

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nine months before returning to Earth. The studies lead author,

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Tomomichi Fujita from Hakkaida University, says most living organisms, including humans,

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can't survive even briefly in the vacuum of space. However,

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the mos sports retain their vitality after nine months of

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direct exposure. He says the findings provide striking evidence that

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the life that's evolved here on Earth possesses, at least

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at a cellular level, intrinsic mechanisms to endure the conditions

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of space.

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Tom A.

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Michi and colleague subjected a well studied moss commonly known

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as spreading earth moss to both real and simulated space

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environment conditions, including high levels of ultraviolet radiation, extreme high

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and low temperatures, and vacuum conditions. They tested three different

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structures from the moss protain mata or juvenile moss, brood

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cells or specialized stem cells that emerge under stress conditions,

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and sporophytes or encapsulated spores, in order to find out

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which are the best chance of surviving in space. The

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authors found that ultraviolet radiation was the toughest environment to survive,

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and the spora sites were by far the most resilient

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of the three moss parts. None of the juvenile mass

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survived high radiation levels or extreme temperatures. The brood cells

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had a high red of survival, but the incse spores

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exhibited a thousand times more tolerance to ultraviolet radiation, and

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the spores were also able to survive and germinate despite

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being exposed to one hundred and ninety six degrees celsius

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for over a week, as well as after living in

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fifty five degrees celsius heat for a month. The samples

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had an eighty percent survival rate and were able to

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successfully germinate when they returned to Earth. The authors then

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analyzed how well the moss survived in a computer model,

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which predicted that the spores could have survived for up

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to five thousand, six hundred days it's around fifteen years.

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The authors say the results demonstrate the remarkable resilience of

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mass spores and revealed the potential of terrestrial plants to

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endure extreme environments. This space time time out to turn

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our eyes to this skies with December SkyWatch. December is

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the twelfth and final month of the year in both

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the Jillian Anchorgorian calendars. December got its name from the

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Latin word decem, meaning ten. That's because it was originally

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the tenth month of the year in the Old Roman calendar,

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which began in March. Of course, the astronomical highlight of

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the month is the December solstice, which this year occurs

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at two or two in the morning of Monday December

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the twenty second Australian Eastern daylight time, that's ten o

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two in the morning of Sunday, December, the twenty first

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US Eastern Standard time, and fifteen oh two in the

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afternoon Greenwich meantime. This is when the sun appears to

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read zenith directly over the Tropic of Capricorn in the

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United States. In the northern hemisphere, it marks the winter solstice,

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signifying the first day of winter. But the good news

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is that from now on the days start to get

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longer again. On the other hand, south of the equator,

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summer has well and truly arrived and the days are

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usually at their warmest. Seasons occur because of the tilt

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of the planet spin axes, which is inclined at twenty

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three point four degrees in relation to the Sun. Now

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generally speaking, Earth's axis always points to the same position

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in space regardless of the position of the Earth as

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it orbits around the Sun. So on the day of

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the December solstice, the earth South pole is tilted towards

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the Sun, so its southern hemisphere gets more daylight and

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more direct sunlight, so it's hotter and its southern hemisphere

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is in summer. Six months later, during the June solstice,

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the north pole is tilted towards the Sun, and so

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it's the northern hemisphere which experiences summer, or the southern

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hemisphere gets less daylight longer nights, and the sunlight strikes

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the surface of the planet at a shallower angle, meaning

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less heat, and so the southern hemispheres in winter. In

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between these two we have the March and September equinox.

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That's when the northern and southern hemispheres get roughly equal

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amounts of daylight and heat, giving us the seasons of

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spring and autumn. Now earlier, we said that generally speaking,

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Earth's axis always points to the same position in space,

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regardless of Earth's orbital position around the Sun. And while

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that's true in our day to day lives, over geologic

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time approximately twenty five thousand, seven hundred and seventy two years,

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a gravity induced effect known as axial procession causes a

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slow and continuous change in the orientation of Earth's rotational axis.

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It can see the same effect in the procession of

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a spinning top as its axis traces out a pair

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of cones joined by the aspises. Earth's precession was historically

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called the procession of the equinoxes, because the equinoxes moved

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westwards along the ecliptic relative to the fixed background stars.

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This slow procession of the Earth axis means that over

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twenty five thou seven hundred and seventy two years, the

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positions of the south and north celestial poles appears to

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move in circles against the space fixed background stars. So

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while today the star Polaris lies approximately at the north

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celestial pole, this will change over time and gam Cepi

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will ultimately become the north star in about three thousand,

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two hundred year from now. It also means the seasons

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would slowly move through different calendar months, but we make

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adjustments to the calendar compensate for that. In most parts

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of the world, the seasons begin on the day of

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the solstice or equinox. These are known as astronomical seasons

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and are based on Earth's orbital position and tilt as

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it travels around the Sun. However, in Australia, seasons begin

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on the first day of a specific calendar month, that

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is March for autumn, June for winter, September for spring,

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and December for summer. These are known as meteorological seasons

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and are based on the annual temperature cycle and divided

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into four consistent three month periods in order to simplify

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weather tracking and climate trends. They align more closely with

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the seasons as they are typically experienced in terms of weather.

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Because of the relatively small amount of elongation in Earth's

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orbit around the Sun, earth seasons are determined by its

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axial tilt rather than orbital distance. Currently, Earth's closest orbital

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position to the Sun, known as perihelian, occurs about two

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weeks after the December solstice, and it's furthest from the Sun,

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known as aphelion, about two weeks after the June solstice.

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That means the next perihelion will occur at four fifteen

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in the morning of Sunday, January fourth, twenty twenty six

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Australian Eastern daylight time. That's when the Earth will be

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just one hundred and forty seven million, ninety nine thousand

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and eight hundred and ninety four kilometers from the Sun.

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That's twelve fifteen in the afternoon of Saturday, January the third,

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US Eastern Standard time, at a quarter past five in

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the afternoon Greenwich meantime. Like axial procession, Earth's orbit also

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changes gradually over geologic time, getting more or less elongated

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and changing perihelian and ophelion. Even the degree of the

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child of Earth's axis changes over thousands of years. Now. Collectively,

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all these changes are known as Malenkovitch cycles, after the

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Serbianjeev physicist and astronomer Miluta Milankovitch, who in the nineteen

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twenties hypothesized that variations in extent tricity axial tild In

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procession resulted in cyclic variations in solar radiation reaching the Earth,

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and that this orbital forcing strongly influenced Earth's climatic patterns. Okay,

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let's start our tour of the December night skies in

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the west, where midway up from the horizon is Former Halt,

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the brightest star, and the constellation Pisces of Strenus the

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southern fish. Former Halt is a very young, white, spiritual type,

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a main sequence star about one point eight times the

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diameter of the Sun and located reasonably nearby, just twenty

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five light years away. A light year is about ten

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trillion kilometers the distance of Ferton can travel in an

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Earth year at three hundred thousand kilometres per second, speed

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of light in a vacuum and the ultimate speed limit

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of the universe. Main Sequence stars are those undergoing hydrogen

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fusion into healium in their cause. Astronomers describe stars in

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terms of spectual types. The classification system based on temperature

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and characteristics. The hottest, most massive, immerse lumine the stars

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are spectro type of blue stars. They're followed by spectual

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type B blue white stars, then spectual type A white stars,

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specual type F whitish yellow stars, spectual type G yellow stars.

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That's where our Sun fits in, by the way. Then

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comes spetual type K orange stars, and the coolest and

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least massive known stars are spectual type M red stars. Now,

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each spectral classification can also be subdivided using a numeric

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digit which represents temperature, with zero being the hottest and

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nine the courlest, and a Roman numeral to represent luminosity.

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So our Sun is a G two V or G

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two five yellow dwarf star. Also included in the stellar

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classification system are spectral types LT and Y, which are

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assigned to failed stars known as brown dwarves, some of

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which were actually born as spectual type M red dwarf stars,

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but they became brown dwarves after losing some of their mass.

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Brown dwarves fit into a unique category between the largest planets,

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which are about thirteen times the mass of Jupiter, and

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the smallest spectrotype m red dwarf stars, which are about

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seventy five to eighty times the mass of Jupiter or

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roughly zero point zero eight solar masses. In two thousand

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and eight, astronomers detected planets orbiting around formal Halt. At

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this stage, it's not known if anyone was looking back.

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Five thousand years ago, the ancient Mesopotamians used former Halt

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to mark the northern hemispheres winter solstice. Now turning to

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the left of former Halt is Akina or Alpha Aridney,

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the brightest star in the constellation Aridnis the River. Located

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one hundred and thirty nine light years away. Akina has

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seven times the diameter of the Sun and rotate some

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fifteen times faster, giving it a very obvious oblate shape.

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The effect of this rapid rotation is that the star

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flattens at its poles that bulges in the middle. In fact,

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its equatorial diameter is about fifty percent greater than its

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polar diameter. It turns out Akinar is actually part of

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a multiple star system, Alpha Aridney A and Alpha Ridney B.

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The primary star Alpha Ridney A is a hot blue

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spectral type B main sequence star. Its smaller companion, Alpha

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Ridney B is a spectral type A white star. They

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pair all but each other around a common center of

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gravity at a distance of about twelve astronomical units. An

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astronomical unit is the average distance between the Earth and

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the Sun about one hundred and fifty million kilometers or

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eight point three light minutes. Moving further left from Akinar

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and just above the horizon is Canopus, the brightest star

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in the southern constellation of Koreina the Kiel, and it's

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also the second brightest star in the night sky after

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Sirius Cainopus is a white giant star nearing the end

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of its life. It's located about three hundred and ten

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light years away. It has about eight and a half

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times the mass of the Sun, but it's expanded out

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to about seventy one times the Sun's diameter. Kinopus has

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some thirteen hundred times the brightness of the Sun, and

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in fact it's the brightest star within seven hundred light

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years of Earth. Its name originates in mythology from the

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time of the Trojan wars and the navigator for Menelaus.

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The King of Sparta, located between Canopus and the Southern

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Cross in Karna and the Trumpet sixteen open star cluster

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is the ticking time bomb that is at a Carena,

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a pair of huge blue stars undergoing the final violent

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phase of their existence for exploding its massive core collapse supernovae.

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The binary system is located some seven thousand, five hundred

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light years away and is buried in the great Nebula

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of Krena, a massive cloud of gas and dust stretching

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some six point five to ten thousand light years wide.

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The stars in et Acarina are classified as highly I

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loomined the spectrotype O blue hypergiants. The primary star is

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estimated to be around one hundred and fifty to two

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hundred times the mass of our Sun, with some five

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million times the Sun's luminosity, eight hundred times its radius,

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and a surface temperature of up to thirty two thousand,

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five hundred kelvin. The primary star in the binary pair

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is also the only known star to produce ultraviolet laser missions.

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The companion star, although smaller than the primary just eighty

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solar masses and twenty times the Sun's radius, is even hotter,

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with surface temperatures of around thirty seven thy two hundred kelvin.

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The two stars all but each other every five point

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five four earth years, ticuned in the gigantic, twin lobed

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cloud of gas and dust known as the homunculous Nebula,

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A bipolar emission and reflection Nebula, the primary star in

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this binary pair, has lost about thirty solar masses in

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recent times. Both at a Karina and its surrounding shroud

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of dust generate huge amounts of infrared radiation, making it

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the brightest infrared source in the sky. Ed Akarina experiences

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tremendous outbursts. During one event, it became almost as bright

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as the star serious known as the Greater eruption, it

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began in eighteen thirty seven and reached its peak in

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eighteen forty three, when it was one of the brightest

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objects in the night sky, for gradually fading away again

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by eighteen fifty six. At Acrena underweight another slightly smaller

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eruption in eighteen ninety two, and has again been steadily

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brightening since about nineteen forty. Both these stars are now

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nearing the end of their lives, and the main sequence

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and they're expected to go Supernerva in an astronomically short

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space of time. When they do go supernerva, Edicrina will

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be visible in the daylight skies even here on Earth.

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In fact, they could become brighter than the full moon

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for months on end. No one knows exactly when Edacrina

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will go super and Ova. A single star, a star

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originally around one hundred and fifty times as massive as

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the Sun, would typically reach core collapse as a will

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free it within about three million years. At low metallicity.

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Many massive stars will collapse directly to form stellar mass

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black holes with no visible explosion, or possibly a subluminous

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super and ova, and a small fraction will produce a

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parent stability super and ova, but its solar metallicity and

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above is expected to be sufficient mass loss before collapse

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to allow a visible Supernerva or peer Now. If there's

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still large amount of expelled material close to the star,

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the shock wave formed by the supernerva explosion impacting on

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the circumstellar material could effectively convert the kinetic energy into radiation,

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resulting in a superluminous supernova or hypererva several times more

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luminous than a typical core collapse supernerva, and much longer

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lasting highly massive progenitors may also eject sufficient nickel to

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cause a superluminous supernerva simply from the radioactive decay now

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the resulting rim that would then form a black hole.

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Since it's highly unlikely that such a massive star could

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ever lose enough mass from its core not to exceed

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the limit for a neutron star about two point three

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or two point four solar masses, but the existence of

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a massive companion star brings many of the possibilities into play.

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If etacrine array was rapidly stripped of its outer layers,

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it might become a less massive WC or WO type star.

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When core collapse is finally reached, this would result in

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a type one B or type one C supernova due

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to the lack of hydrogen sibly helium, and these supernovae

384
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are thought to be possible progenitors for some types of

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gamma ray bursts. Now, a typical core collapse Supernerva at

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the distance of Etycarina would look as bright as the

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planet Venus, the third brightest object in the sky after

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the Sun and Moon. On the other hand, a super

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iluminous supernova could be five magnitudes brighter, possibly the brightest

390
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super and ov and recorded history, but I'm pleased to

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say that based on our current data, Eticrena is not

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expected to produce a gamma ray burst, and its axis

393
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isn't currently aimed anywhere ney of the Earth, and at

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seven five hundred light years away, the star is unlikely

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to directly affect terrest your life forms on Earth thanks

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