Astronomy and Planetary Science Thread

[Flyaway]

Some dark matter haloes could roll through the universe like hollow cosmic Easter Eggs

For some time, scientists have pondered a peculiar question: Can galaxies exist without an outer halo of dark matter? But new research flips this question around, investigating whether some dark matter haloes could exist without galaxies in their centers — like hollow Easter Eggs roaming the cosmos.

Some dark matter haloes could roll through the universe like hollow cosmic Easter Eggs

"A starless or 'dark' dark matter halo would have no galaxy at its center."

www.space.com

 

[FighterJock]

That would throw a a new question about the whole future of Dark Matter Flyaway, it would possibly mean a whole new direction for cosmology if the theory is true.

 

[publiusr]

No one is safe when the Q go bowling---strike!

 

[Rhinocrates]

It turns out that there would be many advantages if the sun went out. Parsnips would be a lot less dangerous, for example.

View: https://www.youtube.com/watch?v=X7sbn9LMZOg&ab_channel=xkcd%27sWhatIf%3F

 

[Flyaway]

Crystal clues on Mars point to watery and possibly life-supporting past

A QUT-led study analysing data from NASA’s Perseverance rover has uncovered compelling evidence of multiple mineral-forming events just beneath the Martian surface – findings that bring scientists one step closer to answering the profound question: did life ever exist on Mars?

The QUT research team led by Dr Michael Jones, from the Central Analytical Research Facility and the School of Chemistry and Physics, includes Associate Professor David Flannery, Associate Professor Christoph Schrank, Brendan Orenstein and Peter Nemere, together with researchers from North America and Europe.

The findings were published in the prestigious journal Science Advances.

“Sulphate minerals exist with different amounts of water in most regions on Mars and allow us to understand how water moved around the planet, which is key to understanding its past habitability,” Dr Jones said.

“However, we don’t yet fully understand how or when these minerals formed. Our team found a way to measure the internal crystal structure of these minerals directly in the rock, which had thought to be impossible on the surface of Mars.”

https://www.eurekalert.org/news-releases/1080512

Related paper:

https://www.science.org/doi/10.1126/sciadv.adt3048

 

[Flyaway]

A planet in a perpendicular orbit around two brown dwarfs:

View: https://youtu.be/VSl7QLU2pVU?si=ojMowzDKNEIRDPmO

 

[NMaude]

Is the Universe spinning? From Anton Petrov:

Hello and welcome! My name is Anton and in this video, we will talk about the study that explains Hubble tension with the idea of rotating universe
Links:
https://academic.oup.com/mnras/articl...https://www.youtube.com/redirect?ev.../538/4/3038/8090496?login=false&v=-lLZSsrRAXk
https://en.wikipedia.org/wiki/G%C3%B6...https://www.youtube.com/redirect?ev...edia.org/wiki/G%C3%B6del_metric&v=-lLZSsrRAXk
https://arxiv.org/pdf/astro-ph/0502237https://www.youtube.com/redirect?ev.../arxiv.org/pdf/astro-ph/0502237&v=-lLZSsrRAXk
Related videos:
https://www.youtube.com/watch?v=dmdrfKETKAE
• Bizarre Discovery Suggests Galaxies S... https://www.youtube.com/watch?v=dmdrfKETKAE
#universe #rotating #hubbletension

0:00 Rotating universe?
0:40 Facts: universe is expanding and many objects too spin
2:20 Why would it be spinning?
3:00 Evidence so far
3:40 Axis of evil mystery
5:00 Godel model and the problems with rotating universe
7:45 All of the evidence points at this being incorrect
8:20 New study: Hubble tension solution
10:20 Conclusions

 

[Flyaway]

Astronomers claim strongest evidence of alien life yet

Astronomers claim to have seen the strongest evidence so far for life on another planet. But other astronomers have urged caution until the findings can be verified by other groups and alternative, non-biological explanations can be ruled out.

“These are the first hints we are seeing of an alien world that is possibly inhabited,” Nikku Madhusudhan at the University of Cambridge told a press conference on 15 March.

…

In 2023, Madhusudhan and his colleagues used the instruments on the James Webb Space Telescope (JWST) to look at K2-18b’s atmosphere in near-infrared light, and again found evidence of water vapour, as well as carbon dioxide and methane. But they also found a tantalising hint of dimethyl sulphide (DMS), a molecule that, on Earth, is produced only by living organisms, mainly marine phytoplankton. The signs for DMS were extremely weak, however, and many astronomers argued that we would need much stronger evidence to be certain about the molecule’s presence.

Now, Madhusudhan and his colleagues have used a different instrument from JWST, the mid-infrared camera, to observe K2-18b. They found a much stronger signal for DMS, as well as a possible related molecule called dimethyl disulphide (DMDS), which is also produced on Earth only by life.

…

The team claims that the detection of DMS and DMDS is at the three-sigma level of statistical significance, which is equivalent to a 3-in-1000 chance that a pattern of data like this ends up being a fluke. In physics, the standard threshold for accepting something as a true discovery is five sigma, which equates to a 1-in-3.5 million chance that the data is a chance occurrence.

Nicholas Wogan at the NASA Ames Research Center in California says the evidence is more convincing than the 2023 results, but it still needs to be verified by other groups. Once the data is made public next week, other researchers can start to confirm the findings, but this could take weeks or months due to the difficulty of interpreting JWST data. “It’s not just like you download the data and you see if there’s DMS – it’s this super complicated process,” says Wogan.

Other scientists are more sceptical about the findings. “These new JWST observations do not offer convincing evidence that DMS or DMDS are present in K2-18b’s atmosphere,” says Ryan MacDonald at the University of Michigan. “We have a boy-who-cried-wolf situation for K2-18b, where multiple previous three-sigma detections have completely vanished when subject to closer scrutiny. Any claim of life beyond Earth needs to be rigorously checked by other scientists, and unfortunately many previous exciting claims for K2-18b haven’t withstood these independent checks.”

…

Madhusudhan and his colleagues calculate that the possible concentrations of DMS and DMDS on K2-18b appear to be over 10 parts per million, thousands of times greater than the concentrations in Earth’s atmosphere. This could indicate a far greater amount of biological activity than on Earth, if the signal proves to be correct, but establishing that the chemicals have a biological origin will take more work, he says.

“We have to be extremely careful,” said Madhusudhan. “We cannot, at this stage, make the claim that, even if we detect DMS and DMDS, that it is due to life. Let me be very clear about that. But if you take published studies so far, then there is no mechanism that can explain what we are seeing without life.”

Ruling out alternative mechanisms could take some time, says Wogan. “Something like this hasn’t really been studied. DMS in a hydrogen-rich atmosphere, we don’t know a tonne about it. There would have to be a lot of work.”

Astronomers claim strongest evidence of alien life yet

On a faraway planet, James Webb Space Telescope has picked up signs of molecules that, on Earth, are produced only by living organisms – but researchers say we must interpret the results cautiously

www.newscientist.com

 

[Michel Van]

John Michael Godier on case of K2-18b

View: https://www.youtube.com/watch?v=82cLukqLgME

 

[FighterJock]

This may be a game changer as far as life beyond our own Solar System.

 

[Justo Miranda]

If the Trump administration continues to cut funding, some scientists will find signs of life anywhere. A few million less and they will declare that they have managed to contact the Vulcans.

 

[Flyaway]

Cambridge University - Strongest hints yet of biological activity outside the solar system:

View: https://youtu.be/sPRr4DgMTxI?si=-ejdA_pI5PhNFxvK

 

[uk 75]

Algae according to a chap on the BBC. So not like us. Oh well Jim. I'm a Doctor not a gardener.

 

[NMaude]

Some more news from Dr. Becky:

Hello and welcome to this episode of Night Sky News for April 2025 with me, astrophysicist Dr Becky Smethurst. This is the show where we chat about what you should look out for in the night sky in the next month, and what’s been happening in space news in the past month. In this episode we’re chatting about all things James Webb Space Telescope, from the announcement of the observations JWST will be making in the next year, to how its spotted Neptune’s aurora for the first time, to the images it captured of the no longer hazardous to Earth asteroid 2024 YR4, and JWST’s discovery of the new record holder for the most distant detection of glowing hydrogen in a galaxy.

Successful JWST proposals for Cycle 4 - https://www.stsci.edu/jwst/science-ex...

Melin et al. (2025) - https://www.nature.com/articles/s4155...
Witstok et al. (2025) - https://www.nature.com/articles/s4158...https://www.youtube.com/redirect?ev...com/articles/s41586-025-08779-5&v=b7Q06j94j9U

00:00 Introduction
01:15 Lyrids Meteor Shower
02:00 Venus, Saturn, Mercury, and the Crescent Moon
02:43 Eta-Aquarids Meteor Shower
04:31 T Coronae Borealis and your astronomy homework
07:28 Mars, Jupiter, and Orion
09:41 April Fool's Astronomy Research Papers
12:17 JWST Year 4 Observation Programs
16:08 JWST observes asteroid 2024 YR4
19:50 JWST spots Neptune's aurora for the first time
24:17 JWST spots most distant detection of glowing hydrogen
29:06 New merch!
30:45 Bloopers

 

[NMaude]

The JWST has detected the star observed eating one of its' planets, from Anton Petrov:

Hello and welcome! My name is Anton and in this video, we will talk about a confirmation of planetary destruction by a distant star
Links:
https://iopscience.iop.org/article/10...https://www.youtube.com/redirect?ev...rticle/10.3847/1538-4357/adb429&v=tLfIx24dn-Y
https://www.eurekalert.org/news-relea...https://www.youtube.com/redirect?ev...kalert.org/news-releases/987734&v=tLfIx24dn-Y
Additional videos:
• Giant Helium Tails Escaping Planet HA...
https://www.youtube.com/watch?v=zDbEFP-qgPI
• We May Finally Know How Hot Jupiter P...

• Unusual Findings From Disintegrating ... https://www.youtube.com/watch?v=uFnX9QcY1Yk

#jwst #jameswebbspacetelescope #exoplanet

0:00 Star swallowed a planet and we just witnessed it
0:40 2020 detection of a strange outburst
1:55 Initial explanation
2:55 JWST discovers something else
4:30 Best explanation so far - hot jupiter destroyed
5:55 What probably happened and additional discoveries
7:35 What will happen next?
8:40 Conclusions and what about the solar system?

 

[NMaude]

PBS Space Time has put out a video about the matter/anti-matter annexation event that occurred 1mS after the Big Bang:

At one-one-thousandth of a second after the Big Bang, the great annihilation event should have wiped out all matter, leaving a universe of only radiation. Why still don't know why any matter survived. Well, a new finding from the LHC brings us one step closer to understanding why there's something rather than nothing.

 

[NMaude]

History of the Universe has a long video about what is hidden at the core of a neutron star:

00:00 Introduction
04:06 A Delicate Balance
14:40 The First Tipping Point
28:24 The Secrets Within
42:12 The Final Tipping Point

I was thinking, @Flyaway , perhaps you should also open a thread about general space news too.

 

[NMaude]

A new video concerning the recent news about the possible presences of life on K2-18b due to the spectroscopic signature of Dimethyl Sulphide:

Astronomers have detected the most promising signs yet of a possible biosignature outside the solar system, although they remain cautious.

Using data from the James Webb Space Telescope (JWST), the astronomers, led by Professor Nikku Madhusudhan from the University of Cambridge, have detected the chemical fingerprints of dimethyl sulfide (DMS) and/or dimethyl disulfide (DMDS), in the atmosphere of the exoplanet K2-18b, which orbits its star in the habitable zone.

On Earth, DMS and DMDS are only produced by life, primarily microbial life such as marine phytoplankton. While an unknown chemical process may be the source of these molecules in K2-18b’s atmosphere, the results are the strongest evidence yet that life may exist on a planet outside our solar system.

The observations have reached the ‘three-sigma’ level of statistical significance – meaning there is a 0.3% probability that they occurred by chance. To reach the accepted classification for scientific discovery, the observations would have to cross the five-sigma threshold, meaning there would be below a 0.00006% probability they occurred by chance.

The researchers say between 16 and 24 hours of follow-up observation time with JWST may help them reach the all-important five-sigma significance. While they are not yet claiming a definitive discovery, the researchers that with powerful tools like JWST and future planned telescopes, humanity is taking new steps toward answering that most essential of questions: are we alone?