Astronomy and Planetary Science Thread

Eyerolls for the clickbait headline but well worth watching.

Some recent analysis of Cassini data on Enceladus indicative of organic chemistry happening in the subsurface ocean, plus news on future missions to Europa and Enceladus.

The creator does name specific studies and research teams, though it would be nice if they provided direct links like Anton Petrov.

View: https://www.youtube.com/watch?v=LjDKhij6ttY
 
We will need an Enceladus probe and lander/submersable to prove that subsurface ocean theory correct Brett Davidson, though I cannot see one getting ready for launch until the 2030s at least sadly.
 
FighterJock said:
We will need an Enceladus probe and lander/submersable to prove that subsurface ocean theory correct Brett Davidson, though I cannot see one getting ready for launch until the 2030s at least sadly.
Click to expand...
Not lander. There have been projects going on around the world for almost 2 decades and they are all about "planetery penetrator".
The tech and research are done and complete from what I see. So yes it will take years before anything gets down the launch pipeline.
 
Reclassifying it was an idiotic move by an egoistic person.
We've had no problem keeping traditional "naming" of things in many other fields even after new insight would beg to differ from the past.
 
 
Last edited:
Mineral False Positives in the Search for Exoplanet Surface Biosignatures

In the search for life in the cosmos, biopigments on exoplanet surfaces are a critical target.

Such pigments have been detected in Earth’s spectrum (by the Galileo spacecraft and in Earthshine) via the “vegetation” or “photosynthesis red edge” (VRE or PRE), a sharp, step-like increase in reflectance with increasing wavelength at ~700 nm. Future space telescopes like the Habitable Worlds Observatory (HWO) are designed to obtain disk-integrated spectra of Earth-like exoplanets in the visible-to-near-infrared to identify such features.

However, there has been no systematic analysis of the occurrence of similar reflectance edges among minerals of non-biological origin. Here, we use existing databases of mineral reflectance spectra to explore the risk that minerals may present false positives in the search for biopigments on exoplanets. We find that several sulfide and tectosilicate minerals, as well as the prebiotically important cyanide salt, potassium ferrocyanide, have PRE-like features.

We characterize these features in order to assess how they may be distinguished from biopigments. We conclude that the future evaluation of the biogenicity of PRE-like features in exoplanet reflectance spectra can be informed by the atmospheric context, but may require an assessment of the prior probability of non-biological and biological hypotheses about the surface materials of exoplanets.
Click to expand...
 
Consistency check casts doubt on evolving dark energy

Cosmologists have long struggled to determine whether the universe's accelerating expansion is being driven by a simple cosmological constant, or whether dark energy's influence is evolving over time. In a new analysis published in Physical Review D, Samsuzzaman Afroz and Suvodip Mukherjee at the Tata Institute of Fundamental Research, Mumbai, have identified a subtle impact on the inference of the nature of dark energy, due to a tiny mismatch between a fundamental cosmological distance relation and two key datasets used to measure the properties of dark energy.
Click to expand...
 
That's because Venus was far too close to the Sun for a start, all the water that was on the surface was boiled away when the Sun was getting hotter and created the surface that we know today and the fact that Venus has no plate tectonics that we know of. Earth will in turn will begin to look like Venus in about a million years time when the Goldilocks Zone moves out towards Mars.
 
 
Last edited:
New Scientist feature on exoplanet research, with an emphasis on TRAPPIST-1, giving an outline of what we know so far and what we might expect. You'll have to scroll a bit to get to the interesting stuff.

https://www.newscientist.com/articl...d-that-is-our-best-hope-of-finding-alien-life

Right now, Allen and several of her colleagues maintain that the observations we have leave us with a roughly 50/50 chance that TRAPPIST-1e has an atmosphere.

She and Espinoza have come up with a clever workaround for the problem of contamination from the star... we should be able to simply subtract what we see in the 1b observations from the 1e observations, leaving behind only the signature of any atmosphere that 1e might have, without any of the contamination from the star that would be in both datasets.

To do this, the team needed more than 100 hours of observation time on JWST to catch 15 transits of the planets in front of their star... it was approved and now there is only one observation left before the data is ready for analysis. “I think by the middle of the year, we should have some preliminary results, and by the end of the year, we should have a pretty solid answer,” says Espinoza.
...

If there is life on TRAPPIST-1e, too, we almost certainly won’t be able to see signs of it with JWST or even the next generation of space telescopes. Even finding an atmosphere on a rocky world this small has been impossible so far, so the sort of close analysis that would reveal biosignatures ... remains out of reach. An atmosphere on such a world would be the best sign we have had so far that a planet is ripe for life and should be searched, though.

Mentioned in the article and related:

https://rockyworlds.stsci.edu/

The program's main objectives are to search for evidence for atmospheres on rocky exoplanets orbiting M-dwarfs via secondary eclipse measurements at 15 um using the MIRI instrument, as well as to characterize the stellar UV properties with HST.

Hmmm, in the main article again:

At first, the signal looked like it might be a sign of methane in the atmosphere, but further study revealed that methane would be incredibly unlikely to survive for long under the levels of radiation present on TRAPPIST-1e.

Now gases that shouldn't last long, if the signal is correct, must therefore be replenished. If, if, if, and so on, the methane signal is real, would that be a potential biosignature? I shouldn't jump to conclusions!
 
Last edited:
From PBS Space Time with some findings about Blackholes:


For a while back there we might be able to avoid the black hole. They’d been lurking as shadows in our theories of gravity forever. Enough mass crammed into a small enough space would lead to a gravitational field at the surface from which not even light could escape from a surrounding surface that we call the event horizon. The event horizon generates paradoxes that worry physicists, and the singularity of infinite density within the black hole worries them even more. And so many brave physicists have fought for centuries to prove that these monsters don’t exist. They hoped nature would step in to save us from the theoretical horror of ultimate gravitational collapse. One of our final hopes is the Planck star—a ball of energy at the heart of the black hole like frozen shards of the Big Bang. Let’s hope they’re real, for physics’ sake.​
Click to expand...
 
Astronomers find interstellar comet 3I/ATLAS hiding in images taken before its official discovery

https://www.space.com/astronomy/com...in-images-taken-before-its-official-discovery

Interstellar Comet 3I/ATLAS Came From a Place Nothing Like Our Solar System
https://scitechdaily.com/interstell...e-from-a-place-nothing-like-our-solar-system/
A comet from beyond our solar system is giving astronomers a rare look at how alien planetary systems may form under conditions very different from those that shaped our own cosmic neighborhood.

The object, called 3I/ATLAS, was discovered less than a year ago as it traveled through our solar system. Although scientists still do not know exactly where it originated, new research led by the University of Michigan suggests the comet formed in an extremely cold region of space.

The study, published in Nature Astronomy, found that 3I/ATLAS contains unusually high levels of deuterium-rich water, often called “heavy water.” The project received support in part from NASA, the U.S. National Science Foundation, and Chile’s National Research and Development Agency.

“Our new observations show that the conditions that led to the formation of our solar system are much different from how planetary systems evolved in different parts of our galaxy,” said Luis Salazar Manzano, lead author of the study and a doctoral student in the U-M Department of Astronomy.
Heavy Water Found in Interstellar Comet

Water is made up of two hydrogen atoms and one oxygen atom, giving it the chemical formula H2O. In normal water, hydrogen atoms contain only a proton. But deuterium is a heavier version of hydrogen that contains both a proton and a neutron.

Researchers discovered that a surprisingly large portion of the comet’s water contains deuterium. Heavy water can also be found on Earth and in comets from our solar system, but the amount detected in 3I/ATLAS was far greater.

“The amount of deuterium with respect to ordinary hydrogen in water is higher than anything we’ve seen before in other planetary systems and planetary comets,” Salazar Manzano said.

According to the researchers, the ratio of deuterium in the comet’s water was about 30 times higher than the levels measured in any comet from our solar system. It was also roughly 40 times greater than the ratio found in Earth’s oceans.
Click to expand...
 
Last edited:
X-ray and γ-ray beam interstellar communication and implications for SETI
https://www.nature.com/articles/s41598-026-45198-6
The possibility of detecting artificial signals transmitted by alien civilizations via collimated X-ray or gamma-ray beams is investigated. The prospect of using such beams for human communication within the solar system and beyond is also discussed. Detector responses were simulated for input signals and analyzed using relative entropy. For simplicity, all signals were assumed to use on-off keying (OOK) modulation. “Real” signals were generated by taking digital files and sequentially feeding their raw binary data to the detector simulator, the resulting normalized information content of the detector signals was plotted and compared to random noise signals. Since jpeg files contain compressed information, these served as a proxy for artificial alien signals. This showed that there is a clear difference in measured information content between natural and artificial signals, even with relatively poor time resolution in the detector causing the signals to be smeared (dead-time/rise-time intervals many times longer than the duration between signal pulses). It was found that so long as the signal lasts for at least several rise-time/dead-time intervals, the distinction between random and artificial signals is obvious.
Click to expand...

Advanced alien civilizations could be communicating 'like fireflies' in plain sight, researchers suggest
https://www.livescience.com/space/e...-fireflies-in-plain-sight-researchers-suggest
A new paper posits that advanced alien civilizations may communicate through subtle flashes, like fireflies do on Earth. The thought experiment suggests that we need to avoid human biases in our search for extraterrestrial life.

some scientists believe that these searches suffer from an "anthropocentric bias" — meaning we're trying to understand nonhuman entities through a distinctly human lens — and do not account for potential civilizations that are wholly different from our own. Due to this bias, we may be overlooking promising signs of life.
Click to expand...

Scientists Recreate Rare Pigment Behind Octopus 'Superpowers'
https://www.sciencealert.com/scientists-recreate-rare-pigment-behind-octopus-superpowers
To get high yields from reluctant bacteria, they used a new method they call "growth-coupled biosynthesis," which incentivized bacteria to make lots of xanthommatin by connecting their survival to pigment production
Click to expand...
 
Last edited:
Astronomers de-fog exoplanet atmospheres with new cloud-detecting method

Discovery by Johns Hopkins researchers of daily cloud cycle on a Hot Jupiter planet provides unique window into its make-up and evolution
Click to expand...

Hubble Sights Galaxy in Transition

This NASA Hubble Space Telescope image reveals an enigmatic galaxy with a bright center and a face that hints at spiral structure, yet it holds no obvious spiral arms. Reddish-brown clumps and filaments of dust partially obscure the galaxy’s full face, while red, blue, and orange light from distant galaxies shines through its diffuse outer regions and dots the inky-black background.
Click to expand...
 
SwRI findings reconsider the existence of Europa’s vapor plumes

Looking back at 14 years of Hubble telescope data for Jupiter’s moon Europa has given Southwest Research Institute (SwRI) scientists a better understanding of its tenuous atmosphere. The findings have cast doubt on previous evidence suggesting that the icy moon intermittently discharges faint water plumes from a presumed subsurface ocean.

“The evidence for water vapor plumes on Europa isn’t as strong as we first understood it,” said SwRI’s Dr. Kurt Retherford, one of the authors of a 2014 paper initially making that assertion. Retherford and his colleagues have recently published a new paper reanalyzing the data.
Click to expand...
 
Consciousness Is the Only Thing That Truly Exists, Scientist Claims

Like matter or gravity, your consciousness may be a fundamental part of reality.
Click to expand...

…

But what if consciousness is actually a fundamental building block of the universe itself, similar to gravity or mass, rather than something the brain creates?
Click to expand...

…

So, if consciousness is indeed a fundamental part of the universe, what does this mean for us as people? For starters, it could answer a host of questions we’ve otherwise viewed as impossible, according to Reggente.

He believes that the “hard problem of consciousness”—or how subjective experience could arise from physical matter—is the obvious case.

“If consciousness is fundamental, the question dissolves: You no more need to explain how the mind emerges from matter than a physicist needs to explain how spacetime emerges from something more basic,” Reggente says. “With this view, the ‘hard problem’ is not a problem at all.”

The same logic applies to cosmological puzzles—or other all-encompassing questions that seem impossible to answer—like, “What came before the Big Bang?” or “What is the universe expanding into?” according to Reggente.
Click to expand...
 
A video from Anton Petrov about how astronomers have been able to characterise the geology of a terrestrial exo-planet:


Hello and welcome! My name is Anton and in this video, we will talk about exogeology
Links:
https://arxiv.org/pdf/2605.00100https://www.youtube.com/redirect?event=video_description&redir_token=QUFFLUhqbVFOMlJLSS1CQTdVcGVHQUk4cDNzRVlfb3o5d3xBQ3Jtc0trYWVQUG1kRzhpRlZrcUxiMlZYaG5TT0ZORVRER2xKYlc0N3l2cF9WdzRQYmc1cGloR1ZldHBHY2V3VHZsTEhHVjJ3dC1WbVBqZk5sd1BnR0JGSnZzRS1jalRFVWs5N0U4X2J0dFpCb1hVdkpBNnU4TQ&q=https://arxiv.org/pdf/2605.00100&v=rCROdUGwVJ8
https://hycean.group.cam.ac.uk/wp-con...https://www.youtube.com/redirect?event=video_description&redir_token=QUFFLUhqbVNYNkNOdjlwYXRNTEpmQ2RLd3RweWM5M1JHUXxBQ3Jtc0tuUnJwSnJnOWhqdE5oMFNBLVRfUWZ1RUV4N3NWakU4S3BkUkxRelJGRVJURElvZW1CQlpEOTdKeUpMNVE0UjRNRFlobGhHclF5TkJfYzA0NGNPa3hwZ09ubTBiWjFsRzFzVlFXd0dKU0JPTjRzbXdYSQ&q=https://hycean.group.cam.ac.uk/wp-content/uploads/2025/04/Transmission_spectroscopy-new.png&v=rCROdUGwVJ8

#exogeology #science #astronomy


0:00 First ever case of exogeology
0:40 What star and planet is this?
2:50 How these observations are done
4:10 Studying the surface and not just the atmosphere
5:40 Results and planetary surface analysis
8:57 Conclusions and implications
Click to expand...
 
Last edited:
Kyplanet discussed the 'cosmic shoreline' a couple of months ago. Here's more.

View: https://www.youtube.com/watch?v=FKSdkVIySq0


The chances of a terrestrial-type planet holding on an atmosphere depends on two main factors: a battle between gravity and heating, plus a magnetic field intervening. On one side of the shoreline, a planet has its atmosphere stripped, on the other, it manages to hold on to it... depending on mass and whether it has a strong enough magnetic field. As we know it, to be habitable, a planet has to be on the outer side of the shoreline but within the habitable zone and around red dwarfs, that could be problematic - the inner planets of TRAPPIST-1 are apparently on the inner side (of both, in the cases of b and c at least).
 
Last edited:
Addendum, tangent, whatever.

Cool Worlds didn't actually mention magnetic fields - probably because they cannot currently be detected around small rocky planets near red dwarfs. Conventional wisdom is that a tidally locked planet won't have its core stirred up enough by its star's field to generate much of a shield. However, as Kyplanet has discussed in a clip mentioned above, multiple worlds in close packed systems would be interacting such that their rotation would at times be chaotic, possibly meaning that they will be rotating within the parent star's field after all for some periods. Might that mean fields that wax and wane according to rotation states?

As you might guess, I'm not a geophysicist.
 
Brett Davidson said:
multiple worlds in close packed systems would be interacting such that their rotation would at times be chaotic, possibly meaning that they will be rotating within the parent star's field after all for some periods. Might that mean fields that wax and wane according to rotation states?
Click to expand...

Also the tidal interactions between them would also constantly heat their interiors to the point that they have a liquid core (The reason why Io still has a molten-core).
 
Bizarre patterns on Venus have scientists puzzled

Bizarre Venus surface formations (or coronae) are likely key to understanding our twin planet's heretofore inscrutable interior. Using NASA Magellan spacecraft data from decades past, Anna Gulcher, an earth and planetary scientist at Germany's University of Freiburg, have created innovative new 3D models of the largest coronae to better understand Venus' puzzling geodynamics.
Click to expand...
 
Mercury's water ice may have been deposited by a larger, slower impactor than previously thought—in only one day

The source of the significant water ice deposits hidden in Mercury's polar regions has been a topic of debate among researchers. A new study, published in the Journal of Geophysical Research: Planets, suggests that these deposits were accumulated in only one Mercurian day (176 Earth days) by a large impactor, such as a comet or asteroid. While previous studies have suggested a similar scenario, this is the first study to fully model the impact. Furthermore, these new models suggest that the impactor may have been larger and slower than previously suggested.
Click to expand...
 
This is hell of Surprise
Seems that Proxima b and d have strong Magnetic Fields
for d with mass of 25% of earth it got magnetic field 25 TIMES STRONGER as Earth field !
could it be that tidal heating or tidal flexing of Proxima sun, on Proxima b and d produce plate tectonic resulting in Strong Magnetic field ?
View: https://www.youtube.com/watch?v=96Aohm1UlYU


Source Papers:
https://arxiv.org/pdf/2605.22925

https://scispace.com/pdf/the-influence-of-thermal-evolution-in-the-magnetic-6bfz0zzsqb.pdf

https://arxiv.org/pdf/2511.21853
 

Similar threads

Back
Top Bottom