Astronomy and Planetary Science Thread

[Justo Miranda]

NASA spacecraft collision may have created a meteor shower that will last for 100 years



https://edition.cnn.com/2024/08/31/science/dimorphos-dart-impact-debris-meteor-shower/index.html
Related paper:

https://arxiv.org/abs/2408.02836

Will it look like a radiant or a rain scattered over time?

 

[NMaude]

These human induced meteor showers no doubt would be called Dimorphids.

 

[Brett Davidson]

Several years old but still cute.

View: https://www.youtube.com/watch?v=HD2zrF3I_II

 

[NMaude]

Another Anton Petrov video concerning the JWST:

Hello and welcome! My name is Anton and in this video, we will talk about another resolution and analysis of bizarre early galaxies found by JWST

Links:
https://arxiv.org/abs/2405.18485https://www.youtube.com/redirect?ev...ttps://arxiv.org/abs/2405.18485&v=WQwwn5cGn5w
https://iopscience.iop.org/article/10...https://www.youtube.com/redirect?ev...rticle/10.3847/1538-3881/ad57c1&v=WQwwn5cGn5w

Little red dots: • Nobody Can Explain 1000s of Strange L... https://www.youtube.com/watch?v=xkdAbOS9AcA&t=0s
Most distant galaxy: • Galactic Distance Record Broken Again... https://www.youtube.com/watch?v=5B8-xUabZsw&t=0s

#jwst #jameswebbspacetelescope #astronomy

0:00 Mystery of ancient galaxies seen by JWST
1:15 Little red dots
2:20 First study suggests powerful black holes
4:10 Still some unresolved issues
5:30 Analysis of farthest galaxies ever found
6:55 Second study suggests powerful star formation
7:45 Surprising discoveries
9:00 Conclusions

 

[Flyaway]

Giant impact on early Ganymede and its subsequent reorientation

Abstract
Ganymede has an ancient impact structure called a furrow system. The furrow system is the largest impact structure in the outer solar system, and the impact should have significantly affected Ganymede’s early history; however, its effects are poorly understood. No attention has been given to the center of the furrow system coinciding with Ganymede's tidal axis, indicating that mass redistribution induced by the furrow-forming impact caused a reorientation (true polar wander) of Ganymede. We propose that the impact ejecta created a mass anomaly that reoriented the impact site toward the tidal axis. We found that an impactor with a radius of 150 km and an incidence angle between 60° and 90° most accurately reproduces the current location of the furrow system. We predict that future explorations would reveal remnant topographic profiles or gravity anomalies associated with the furrow-forming impact and reorientation. Additionally, various possible explanations for the reorientation of Ganymede, such as an impactor-origin mascon beneath the basin or a thickness variation in the lithosphere, should be studied.

https://www.nature.com/articles/s41598-024-69914-2

 

[Flyaway]

The Martian polar caps are not created equally—here's why

People have observed the bright Martian poles wax and wane for centuries, but only within the last 50 years have scientists discovered that they are mostly comprised of carbon dioxide cycling in and out of the atmosphere to the rhythm of the seasons. But exactly how this happens is a complex interplay of planetary processes that scientists are continually teasing out.

https://phys.org/news/2024-09-martian-polar-caps-equally.html
Related paper:

https://www.sciencedirect.com/science/article/pii/S0019103523003809?via=ihub

 

[Justo Miranda]

The Martian polar caps are not created equally—here's why



https://phys.org/news/2024-09-martian-polar-caps-equally.html
Related paper:

https://www.sciencedirect.com/science/article/pii/S0019103523003809?via=ihub

Possibly the differences are caused by the oscillations in the axis of rotation of the planet that will be greater than those of the earth because it lacks large satellites to balance it.

 

[NMaude]

More Brown Dwarf surprises from Anton Petrov:

Hello and welcome! My name is Anton and in this video, we will talk about exciting discoveries about brown dwarfs

Links:
https://arxiv.org/abs/2408.12639https://www.youtube.com/redirect?ev...ttps://arxiv.org/abs/2408.12639&v=OYWZaSJKlYU
https://academic.oup.com/mnras/articl...https://www.youtube.com/redirect?ev.../532/2/2207/7712857?login=false&v=OYWZaSJKlYU
https://iopscience.iop.org/article/10...https://www.youtube.com/redirect?ev...rticle/10.3847/1538-4357/acb8b7&v=OYWZaSJKlYU
https://arxiv.org/pdf/2408.04475https://www.youtube.com/redirect?ev...ttps://arxiv.org/pdf/2408.04475&v=OYWZaSJKlYU

Previous videos:
https://www.youtube.com/watch?v=iCywIjuTX5E&t=0s
• Exciting Discoveries About Brown Dwar...

• Revealing The Surface of Luhman 16 - ... https://www.youtube.com/watch?v=TVv0-FDIwXM&t=0s

#browndwarf #astronomy #planethttps://www.youtube.com/hashtag/planet

0:00 Brown dwarfs
0:48 JWST discoveries
1:25 Formed as pairs but become solo
3:00 Lowest mass possible and brown dwarfs in a nearby cloud
5:20 Formation of a tiny brown dwarf
6:20 Luhman 16 and its weather
9:20 Conclusions

 

[Brett Davidson]

More Brown Dwarf surprises from Anton Petrov:

I think we're only just beginning to really learn about these objects.

 

[Flyaway]

Meet Phaethon, a weird asteroid that thinks it’s a comet – our new research may explain what’s going on

I led newly published research aimed at addressing this puzzle by simulating the intense solar heating that Phaethon experiences during its perihelion.

We used chips from a rare group of meteorites called the CM chondrites, which contain clays that are believed to be similar to Phaethon’s composition. These were heated in an oxygen-free environment multiple times, simulating the hot-cold/day-night cycles that occur on Phaethon when it is close to the Sun.

The results were surprising. Unlike other volatile substances that would typically be lost after a few heating cycles, the small quantities of sulphurous gases contained in the meteorites were released slowly, over many cycles.

https://theconversation.com/meet-ph...ew-research-may-explain-whats-going-on-237903
Related paper:

https://www.nature.com/articles/s41467-024-51054-w

 

[Brett Davidson]

https://pluto.jhuapl.edu/News-Cente...7d9yW9pkUj-70UrJSw_aem_RGKpxQfvABr2-VoUWpSaSg
The new result has multiple implications. One is that the Kuiper Belt may extend farther than formerly believed, or that there is a second Kuiper Belt beyond the one observationally discovered in the 1990s. A second implication is that the New Horizons spacecraft, now about 60 times as far from the Sun as Earth, is not past the Kuiper Belt as earlier expected.

 

[Flyaway]

Outer solar system is more populated than previously thought, research reveals

Survey observations using the Subaru Telescope's ultra-widefield prime focus camera have revealed that there may be a population of small bodies further out in the Kuiper Belt waiting to be discovered.

…

"The most exciting part of the HSC observations was the discovery of 11 objects at distances beyond the known Kuiper Belt," says team member Dr. Fumi Yoshida, from the University of Occupational and Environmental Health Sciences and the Planetary Exploration Research Center, Chiba Institute of Technology.

Many of the objects discovered with HSC are located at distances of 30–55 astronomical units (au) from the sun (1 au corresponds to the distance between the sun and Earth) and are thought to be within the known Kuiper Belt.

On the other hand, the team was not expecting what appears to be a cluster of objects in the 70–90 au region and a valley between 55 au and 70 au (where only a small number of objects are distributed, see figure below). Such a valley had not been reported in other observations.

https://phys.org/news/2024-09-outer-solar-populated-previously-thought.html
Two related papers:

https://arxiv.org/abs/2403.04927
https://arxiv.org/abs/2407.21142

 

[Flyaway]

Astronomers discover iron winds on an ultra-hot exoplanet

An international team of astronomers, including scientists from the University of Geneva (UNIGE) and the PlanetS National Center of Competence in Research, has identified the presence of iron winds in the atmosphere of the ultra-hot Jupiter WASP-76 b.

…

For this new study, the team of astronomers focused on the day side of WASP-76 b, which has a temperature of 2400 degrees Celsius, by observing it at high spectral resolution in the visible light. The main result was the detection of a stream of iron atoms moving from the lower to the upper layers of the planet's atmosphere.

https://phys.org/news/2024-09-astronomers-iron-ultra-hot-exoplanet.html
Related paper:

https://www.aanda.org/articles/aa/full_html/2024/09/aa49935-24/aa49935-24.html

 

[Flyaway]

Expert explains evidence for planetary formation through gravitational instability

But in a new paper published today in Nature, MIT Kerr-McGee Career Development Professor Richard Teague and his colleagues report evidence that the movement of the gas surrounding the star AB Aurigae behaves as one would expect in a gravitationally unstable disk, matching numerical predictions.

Their finding is akin to detecting the snowplow that made the pile. This indicates that gravitational collapse is a viable method of planetary formation. Here, Teague, who studies the formation of planetary systems in MIT's Department of Earth, Atmospheric and Planetary Sciences (EAPS), answers a few questions about the new work.

https://phys.org/news/2024-09-expert-evidence-planetary-formation-gravitational.html
Related paper:

https://www.nature.com/articles/s41586-024-07877-0

 

[Flyaway]

Not everyday you hear about someone shooting a telescope.

Astrum - Malicious attack on $5 million dollar telescope. Scientists don’t care:

View: https://youtu.be/59cw_bDbEqA?si=zu1BTh7cXSLZjCMw

 

[NMaude]

Here's a video by Anton Petrov about a missing link in the evolution of animal life which should be a useful reference for emo-biologists aka astro-biologists:

Hello and welcome! My name is Anton and in this video, we will talk about the missing link between single cell and multicellular life - Barroeca monosierra
Links:
https://journals.asm.org/doi/10.1128/...https://www.youtube.com/redirect?ev...m.org/doi/10.1128/mbio.01623-24&v=2vzOXj_lh58
https://www.hhmi.org/news/newly-disco...https://www.youtube.com/redirect?ev...rganisms-band-together-flip-out&v=2vzOXj_lh58
Gut bacteria:
https://www.youtube.com/watch?v=e10yOoP-x3g&t=0s
• Mindblowing Discoveries About Bacteri...

• Incredible Discoveries About Viruses ... https://www.youtube.com/watch?v=e-UxDO-3CZI&t=0s

0:00 Mono lake discovery
0:55 Missing step between unicellular and multicellular life
1:20 Choanoflagellates
2:30 Complex colonies
3:30 Simplest animal for comparison
4:30 Colonial behavior never seen before
5:40 Microbiome discovery suggest unusual symbiosis
6:45 Similarity to embryos
7:30 What are these bacteria for though?
8:50 Conclusions

 

[NMaude]

Anton Petrov has just uploaded a video concerning a technical breakthrough with atomic-clocks:

Hello and welcome! My name is Anton and in this video, we will talk about new atomic clocks and how it could help us solve quantum physics mysteries
Links:
https://journals.aps.org/pra/abstract...https://www.youtube.com/redirect?ev...act/10.1103/PhysRevA.110.032602&v=MNzi0k5utkQ
https://www.nist.gov/news-events/news...https://www.youtube.com/redirect?ev...ck-pushes-new-frontiers-physics&v=MNzi0k5utkQ
https://journals.aps.org/prl/abstract...https://www.youtube.com/redirect?ev.../10.1103/PhysRevLett.133.023401&v=MNzi0k5utkQ
Other videos:
https://www.youtube.com/watch?v=b2DN1WndqvM&t=0s
• NASA Tested Deep Space Atomic Clock F...

• Most Accurate Time Keeping Device in ... https://www.youtube.com/watch?v=ogDBFD7tr90&t=0s

0:00 How I almost got atomic clock as a present
2:03 NIST announces most accurate clock ever 3:05 How atomic clocks work
6:05 Can we measure Einstein's principle using these clocks?
7:25 How we can combine quantum effects with atomic clocks
9:30 What this experiment could achieve - quantum version of twin paradox
10:50 What questions this may answer
12:10 Conclusions
#physics #atomicclock #quantum

 

[Flyaway]

The article doesn’t say if this removes the need for Mike Brown’s hypothetical planet nine.

Solution to a cosmic mystery—the eccentric orbits of trans-Neptunian objects

New evidence suggests that billions of years ago, a star may have passed very close to our solar system. As a result, thousands of smaller celestial bodies in the outer solar system outside Neptune's orbit were deflected into highly inclined trajectories around the sun. It is possible that some of them were captured by the planets Jupiter and Saturn as moons.

…

"The best match for today's outer solar systemthat we found with our simulations is a star that was slightly lighter than our sun—about 0.8 solar masses," explains Pfalzner's colleague Amith Govind. "This star flew past our sun at a distance of around 16.5 billion kilometers. That's about 110 times the distance between Earth and the sun, a little less than four times the distance of the outermost planet Neptune."

…

”Some of these objects could have been captured by the giant planets as moons," says Simon Portegies Zwart from Leiden University. "This would explain why the outer planets of our solar system have two different types of moons."

https://phys.org/news/2024-09-solution-cosmic-mystery-eccentric-orbits.html
Related papers:

https://www.nature.com/articles/s41550-024-02349-x
https://iopscience.iop.org/article/10.3847/2041-8213/ad63a6

 

[Flyaway]

Gravitational waves unveil previously unseen properties of neutron stars

A better understanding of the inner workings of neutron stars will lead to a greater knowledge of the dynamics that underpin the workings of the universe and also could help drive future technology, said the University of Illinois Urbana-Champaign physics professor Nicolas Yunes. A new study led by Yunes details how new insights into how dissipative tidal forces within double—or binary—neutron star systems will inform our understanding of the universe.

…

The properties of neutron stars imprint onto the gravitational waves they emit. These waves then travel millions of light-years through space to detectors on Earth, like the advanced European Laser Interferometer Gravitational-Wave Observatory and the Virgo Collaboration," Yunes said. "By detecting and analyzing the waves, we can infer the properties of neutron stars and learn about their internal composition and the physics at play in their extreme environments."

…

Using data from the gravitational wave event identified as GW170817, Yunes, along with Illinois researchers Justin Ripley, Abhishek Hegade and Rohit Chandramouli, used computer simulations, analytical models and sophisticated data analysis algorithms to verify that out-of-equilibrium tidal forces within binary neutron star systems are detectable via gravitational waves. The GW170817 event was not loud enough to yield a direct measurement of viscosity, but Yunes' team was able to place the first observational constraints on how large viscosity can be inside neutron stars.

https://phys.org/news/2024-09-gravitational-unveil-previously-unseen-properties.html
Related paper:

https://www.nature.com/articles/s41550-024-02323-7

 

[Flyaway]

Nearby super-Earth has a sulfur-rich atmosphere, Webb observations suggest

Using the James Webb Space Telescope (JWST), astronomers from the Space Telescope Science Institute (STScI) in Baltimore, Maryland and elsewhere have conducted transmission spectroscopy of a nearby super-Earth exoplanet known as L98-59 d. Results of these observations, available in a research paper published August 28 on the pre-print server arXiv, suggest that the planet has a sulfur-rich atmosphere.

…

According to the paper, the atmosphere of L98-59 d showcases a high abundance of hydrogen sulfide (H2S) and sulfur dioxide (SO2). They excluded the possibility that this could be caused by stellar contamination.

https://phys.org/news/2024-09-nearby-super-earth-sulfur-rich.html
Related paper:

https://arxiv.org/abs/2408.15855

 

[NMaude]

A short clip about a photograph the HST took of the Bubble nebula:

NASA's Hubble Space Telescope has captured a stunning image of the Bubble Nebula, a glowing cosmic bubble formed by the intense winds of a massive star.

In this video, Dr. Ken Carpenter dives into the mesmerizing details of the Bubble Nebula and discusses how Hubble's observations continue to reveal the intricate beauty and complexity of the universe.

The star that illuminates the Bubble Nebula is BD+60°2522 an O6.5 class supergiant star which is only two millions years old and at 44 solar-masses will go boom in a Type-II core-collapse supernova probably during the next million or two years.

 

[NMaude]

Here's a video concerning the JWST and images of the oldest known star, Earendil:

Take a look at the most distant star we have ever seen. This tiny red dot in the Sunrise Arc Galaxy is actually a single star- Earendel- and it is 12.9 billion light-years away. Today, we'll explore how astronomers first detected this ancient star, first with the Hubble Space Telescope and then with the James Webb Space Telescope, and the miracle that makes it visible to us despite its mind-blowing distance. We've layered these beautiful photos into a mind blowing animation at the end, just to show the scale of this distance!

Earendel is located in the Cetus constellation.

Fans of J.R.R. Tolkien will certainly recognize the name. This star was nicknamed Earendel by the discoverers in honor of the character from Tolkien's legendarium. Eärendil is the name of a half-elven character mentioned in several of J. R. R. Tolkien's books (The Silmarillion and The Lord of the Rings, primarily) who travelled through the sky with a radiant jewel that appeared as bright as a star. NASA astronomer Michelle Thaller confirmed that the reference to Tolkien was intentional. Pretty cool! Tolkien derived this name from an Old English poem in which it meant 'morning star' or 'rising light'.

 

[NMaude]

The Science Asylum channel has put out this video about white-dwarf stars:

White dwarfs are made of degenerate matter, so compact there isn't room for atoms to exist. And, believe it or not, we discovered that using a model from a completely different context.

Watch this video ad-free on Nebula:https://nebula.tv/videos/scienceasylu...https://www.youtube.com/redirect?ev...covered-this-matter-by-accident&v=1QVPjrUdp0k

Nick Lucid - Host, Writer, Editor, Animator
Em Lucid - Producer
________________________________
VIDEO ANNOTATIONS/CARDS

Sirius Binary System:
• The Star That Keeps Getting Weirder https://www.youtube.com/watch?v=JPBJPqYCGCA&t=0s
Fermi Paradox:

View: https://www.youtube.com/watch?v=SbfQkIeunMY&t=0s

SOURCES

Fermi's Paper:
https://link.springer.com/article/10.... (German)
https://arxiv.org/abs/cond-mat/9912229(English)

Helium-3:
https://arxiv.org/abs/cond-mat/9503150https://www.youtube.com/redirect?ev.../arxiv.org/abs/cond-mat/9503150&v=1QVPjrUdp0k

Entropy of Ideal Gas:
https://web.mit.edu/16.unified/www/FA...https://www.youtube.com/redirect?ev...hermodynamics/notes/node40.html&v=1QVPjrUdp0k
http://hyperphysics.phy-astr.gsu.edu/...https://www.youtube.com/redirect?ev....edu/hbase/Therm/entropgas.html&v=1QVPjrUdp0k

Fermi-Dirac Distribution:
http://hyperphysics.phy-astr.gsu.edu/...https://www.youtube.com/redirect?ev...su.edu/hbase/quantum/disfd.html&v=1QVPjrUdp0k

Fowler's Paper:
https://academic.oup.com/mnras/articl...https://www.youtube.com/redirect?ev.../mnras/article/87/2/114/1058897&v=1QVPjrUdp0k

Dirac's Paper:
https://royalsocietypublishing.org/do...

TIME CODES
00:00 Intro
00:30 Enrico Fermi
00:52 Fermi Gases
01:25 3rd Law of Thermodynamics
02:20 Quantum Mechanics
03:02 Fermi-Dirac Statistics
04:06 White Dwarfs
04:43 Hydrostatic Equilibrium
05:17 Fermions
06:00 Surface Gravity
06:43 Degenerate Matter
07:34 Electron Degeneracy Pressure
08:37 Closing Thoughts
09:21 Featured Comment

 

[Justo Miranda]

The article doesn’t say if this removes the need for Mike Brown’s hypothetical planet nine.

Solution to a cosmic mystery—the eccentric orbits of trans-Neptunian objects



…



…



https://phys.org/news/2024-09-solution-cosmic-mystery-eccentric-orbits.html
Related papers:

https://www.nature.com/articles/s41550-024-02349-x
https://iopscience.iop.org/article/10.3847/2041-8213/ad63a6

Nemesis???

https://en.wikipedia.org/wiki/Nemesis_(hypothetical_star)

 

[NMaude]

Nemesis???

https://en.wikipedia.org/wiki/Nemesis_(hypothetical_star)

Possibly, however I suspect the star in question was one of the Sun's many stellar siblings in the stellar nursery where the Solar-system was formed, IIRC astronomers estimate that the Sun is one of hundreds of main-sequence stars that formed in the same stellar nursery.

 

[Flyaway]

Deep imaging techniques reveal that galaxies are much much bigger than previously thought

If this galaxy is typical, then the study, published today in Nature Astronomy, indicates that our galaxy is already interacting with its closest neighbor, Andromeda.

…

A new study, however, has observed the circumgalactic medium of a star-bursting galaxy 270 million light years away, using new deep imaging techniques that were able to detect the cloud of gas glowing outside of the galaxy 100,000 light years into space, as far as they were able to look.

https://phys.org/news/2024-09-deep-imaging-techniques-reveal-galaxies.html
Related paper:

https://www.nature.com/articles/s41550-024-02365-x

 

[Flyaway]

New EHT test observations have achieved the highest-resolution detections of black holes from Earth. #blackholes #EHT #eventhorizon 1/

Image: Artist's impression showing radio signals from a distant galaxy detected by radio observatories worldwide. Credit: ESO/M. Kornmesser

The test was carried out by two small subarrays of the EHT—made up of @almaobs and @ApexTelescope in Chile, IRAM in Spain, the NOEMA in France, the Submillimeter Array (SMA) in Hawai'i, and the Greenland Telescope. 2/

Credit: CfA/SAO, Mel Weiss @melweiss

The new observations were made at 345 GHz, much higher than the previous 230 GHz. The higher the frequency, the sharper the image as seen here in this simulated side-by-side comparison of M87*. 3/

Credit: EHT, D. Pesce, A. Chael

This composite simulated image shows how M87* is seen by the EHT at 86 GHz (red), 230 GHz (green), and 345 GHz (blue). 345 GHz provides a more compact and sharper view of black holes, revealing structure, size, and shape with more clarity. 4/

Credit: EHT, D. Pesce, A. Chael

Ultimately, the increase in capability will make images of supermassive black holes 50% crisper and open new windows on the mysteries of these cosmic beasts. Read the open access paper below. 5/

https://iopscience.iop.org/article/10.3847/1538-3881/ad5bdb

https://twitter.com/x/status/1828451388470501743

View: https://twitter.com/ehtelescope/status/1828451388470501743

https://twitter.com/x/status/1828451393944133714

View: https://twitter.com/ehtelescope/status/1828451393944133714


Additional information in the following press releases:
https://cfa.harvard.edu/news/event-...ighest-resolution-black-hole-detections-earth
https://www.eso.org/public/news/eso2411/
https://public.nrao.edu/news/astronomers-make-highest-resolution-observations-ever-from-earth/
https://www.mpifr-bonn.mpg.de/pressreleases/2024/9?c=9060
https://www.almaobservatory.org/en/...chieve-the-highest-resolution-yet-from-earth/

 

[Michel Van]

Why Moons Don't have rings in solar system ?

View: https://www.youtube.com/watch?v=fd-OlUcgcSc

0:00 Why no rings around moons?
0:50 So many rings everywhere though
1:40 Asteroid rings
2:03 Dwarf planet rings
2:38 How an exomoon started the idea of cronomoons
4:10 Why moons should have rings
4:55 Unexpected conclusions from the study - all moon should have rings
6:40 Rings would be very strange
7:02 So here's the actual answer
8:05 Conclusions and implications

Sources:
https://arxiv.org/abs/2408.10643https://academic.oup.com/mnras/article/512/1/1032/6461099

 

[FighterJock]

An interesting thought Michel Van. There was a theory about the formation of Saturn's rings that states that they were formed when a Moon or Moon's got too close to Saturn and broke up so that could also explain it, that could also explain why there are no rings around Moons of the planets.

 

[Justo Miranda]

An interesting thought Michel Van. There was a theory about the formation of Saturn's rings that states that they were formed when a Moon or Moon's got too close to Saturn and broke up so that could also explain it, that could also explain why there are no rings around Moons of the planets.

https://en.wikipedia.org/wiki/Roche_limit

 

[FighterJock]

Thanks Justo Miranda, I never had known that the theory was known as the Roche limit. Highly fascinating link too.

 

[NMaude]

Anton Petrov has a video out about recent discoveries concerning Earth's interior:

Hello and welcome! My name is Anton and in this video, we will talk about a donut inside planet Earth
Links:
https://www.science.org/doi/10.1126/s...https://www.youtube.com/redirect?ev....org/doi/10.1126/sciadv.adn5562&v=GljciCwOfyc
Previous videos:
• Evidence Of a Structure Wrapped Aroun...
https://www.youtube.com/watch?v=e7lAwd-zf4c&t=0s
• Structures Inside Earth That May Be U...

• Major Evidence For Another Structure ... https://www.youtube.com/watch?v=EiR9xTHuLr4&t=0s

#earth #donut #core

0:00 Discoveries from within Earth
1:50 New discovery: donut structure inside Earth
2:25 Earth structure in a nutshell
4:00 Understanding the chemical composition and how seismic waves help
4:50 What was done in this study
5:30 Overall discoveries
6:45 Why this is important
7:35 Conclusions and implications

 

[Michel Van]

some theory over exobiology

View: https://www.youtube.com/watch?v=ExOYNjxpMu8

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

 

[NMaude]

A new video by Anton Petrov about whether or not the most powerful astronomical explosion detected violate Einstein's theory of relativity:

Hello and welcome! My name is Anton and in this video, we will talk about an intriguing analysis that used the most powerful explosion we've ever seen to analyze Einsteinian theories
Links:
https://arxiv.org/pdf/2402.06009https://www.youtube.com/redirect?ev...ttps://arxiv.org/pdf/2402.06009&v=DoFwVrMmkc0
Previous videos:
• Most Powerful Explosion Since the Big...
https://www.youtube.com/watch?v=WiafKwbt4Qc&t=0s
• Speed of Light Shift and Dilation - B...

• Most Powerful Explosion Humanity Has ... https://www.youtube.com/watch?v=RHSoIDmolBE&t=0s

0:00 Do Einsteinian principles hold at high velocities?
1:00 Lorentz and space time
2:10 Speed of light invariance
3:10 Quantum gravity ideas
4:35 LHAASO detections of gamma rays
6:20 Propositions from quantum gravity
7:20 New study and the results
7:40 Surprising conclusions and implications
#boat #grb #einstein

 

[Justo Miranda]

some theory over exobiology

View: https://www.youtube.com/watch?v=ExOYNjxpMu8

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

Proxima B is a red dwarf, this type of star emits frequent flares, the rocky planets located in the habitable zone are not a good place to camp.

https://en.wikipedia.org/wiki/Flare_star

 

[FighterJock]

And astronomers think that Proxima Centauri emits more flares than our Sun does, so it would mean that there would probably be no life like us on Proxima Centauri B.

 

[Flyaway]

New observations shed more light on the nature of a millisecond pulsar binary

Using ESA's XMM-Newton satellite, European astronomers have performed X-ray observations of a millisecond pulsar binary known as PSR J1431−4715. Results of the observational campaign, published September 3 on the pre-print server arXiv, provide more insights into the nature of this system.

https://phys.org/news/2024-09-nature-millisecond-pulsar-binary.html
https://arxiv.org/abs/2409.02075
Formation of super-Earths proven limited near metal-poor stars

In a new study, astronomers report novel evidence regarding the limits of planet formation, finding that after a certain point, planets larger than Earth have difficulty forming near low-metallicity stars.

https://phys.org/news/2024-09-formation-super-earths-proven-limited.html
https://iopscience.iop.org/article/10.3847/1538-3881/ad6570

 

[Flyaway]

https://www.esa.int/Science_Explora...gcontext=2aeed2d3-44b9-4cdc-82e5-2ee300d4f3b7

 

[Flyaway]

New dense sub-Saturn exoplanet discovered

According to the study, TOI-6651 b has a radius of about 5.09 Earth radii, while its mass is 61 times greater than that of our planet. This gives a bulk density at a level of 2.52 g/cm3, which makes it the densest sub-Saturn so far detected with TESS.

TOI-6651 b orbits its host every 5.05 days on an orbit with an eccentricity of 0.09, at a distance of approximately 0.06 AU from it. The planet's equilibrium temperature is estimated to be 1,493 K.

…

Summing up the results, the researchers underlined that the unusual properties of TOI-6651 b pose a challenge to the known planet formation theories.

"The existence of TOI-6651b challenges conventional planet formation theories and could be a result of merging events or significant atmospheric mass loss through tidal heating, highlighting the complex interplay of dynamical processes and atmospheric evolution in the formation of massive dense sub-Saturns," the scientists conclude.

https://phys.org/news/2024-09-dense-saturn-exoplanet.html
https://www.aanda.org/component/article?access=doi&doi=10.1051/0004-6361/202450934

 

[NMaude]

According to the study, TOI-6651 b has a radius of about 5.09 Earth radii, while its mass is 61 times greater than that of our planet.

I wonder if it's massive enough to a layer of liquid metallic-hydrogen surrounding its' core? Does anyone know what the minimum mass for a gas-giant is to form liquid metallic-hydrogen in its' interior?