Astronomy and Planetary Science Thread

James Webb Space Telescope discovers smallest 'failed stars' ever seen

Astronomers have discovered a batch of nine new brown dwarfs, also known as "failed stars," including the two smallest examples of these curious celestial objects ever seen.

The new find could help better define the mass dividing line between large planets and small brown dwarfs, as well as that between large brown dwarfs and small stars.

"The new brown dwarfs are the least massive known brown dwarfs," lead researcher Kevin Luhman of Pennsylvania State University told Space.com. "They place a new constraint on the lowest mass at which brown dwarfs exist."

"In addition, one of the brown dwarfs near two Jupiter masses exhibits evidence of a disk of gas and dust, indicating that it may have the raw materials for making planets," Luhman said. "So it is possible that the planetary systems exist in which the central 'sun' is only twice the mass of Jupiter."



The new brown dwarfs also exhibit signals from an unidentified hydrocarbon, a chemical compound composed solely of hydrogen and carbon atoms. Its origin is a mystery, team members said.

"The presence of an unidentified, non-methane hydrocarbon is completely unexpected and unexplained," Luhman said. "Because of the presence of that hydrocarbon, we have proposed a new spectral class (H) that is defined by the presence of that species."



Two of these candidates could have masses as low as the mass of Jupiter, hinting at a further shakeup of our concept of the brown dwarf mass range.


Related paper:

 
This is where having a permanent base on the Moon's far side would be helpful for radio-astronomy as the Moon's bulk would block radio "Noise" from the Earth.


That is true, because a base located there would be free of electromagnetic interference from the earth, but that should not serve as a justification for the enormous expenses of those who want a lunar human colony. Robots can do a great job there by building a huge radio telescope. Thanks to the low gravity and lack of oxidation. Data would be transmitted to Earth by satellites in geosynchronous orbit. Much cheaper and infinitely less dangerous.
 
Dark Stars, i.e. early stars composed almost entirely of hydrogen and helium but powered by Dark Matter, could form in zero metallicity clouds located close to the center of high redshift Dark Matter halos.

As a footnote, contrary to the illustration, 'Dark Stars' would not actually be dark in visible light. 'Dark matter' is so-called because it normally interacts weakly only through gravitation with baryonic matter. According to the hypothesis used here, the annihilation of dark matter would heat concentrations of 'normal' matter so that they emit visible radiation and would in fact appear to be very bright.
 
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How the Vera Rubin Observatory will transform astronomy

With the ability to scan the entire southern night sky every three days, the huge Vera Rubin Observatory could be about to start solving the mysteries of the universe, from dark matter to Planet Nine. Our US editor Chelsea Whyte travelled to the top of Cerro Pachón, a Chilean mountain, to visit the observatory as it came online.

View: https://www.youtube.com/watch?v=T2NEUjUOf_g
 
The most energetic subatomic particle detected may possibly be Dark Matter, from Anton Petrov:


0:00 Unexplained Event KM3-230213A
1:55 What happened in 2023
4:00 Why this is mysterious
7:05 New study and why it's so interesting
9:10 Why dark matter is doubted
9:30 Why this might be dark matter after all
11:30 What needs to be done to confirm this
12:40 Conclusions
 
Astrum has put out video concerning some recent discoveries concerning Tethys made from examining Cassini photographs:


What could survive an impact so massive it should have shattered the entire world into pieces? Saturn's scarred survivor Tethys holds dark secrets - a massive crater that spans half its diameter, a colossal trench wrapping around its body, and a bizarre thermal anomaly that looks just like Pac-Man. In this video, we uncover the shocking secrets frozen in Tethys' icy shell and discover how this scarred world became one of the solar system's most remarkable survivors.
▀▀▀▀▀▀
1:30 Discovery
2:19 The Ice World
4:19 Ithaca Chasma: The Great Crack
5:14 Bursting Open
8:12 Odysseus Crater
9:15 Healing Ancient Scars
12:09 The Pac-Man Phenomenon
13:15 Why Does Tethys Look Like Pac-Man?
15:58 The Survivor

▀▀▀▀▀▀
References:

“Tethys”, via nasa.gov https://astrumspace.info/tethys
“Cassini captures Tethys in all her glory”, via newscientist.com https://astrumspace.info/cassinitethys
“Photometric Modeling and VIS-IR Albedo Maps of TethysFrom Cassini-VIMS”, via wiley.com https://astrumspace.info/photometricm...
“Cassini's geological and compositional view of Tethys”, via sciencedirect.com https://astrumspace.info/tethyscompos...
“The Geology of Tethys”, via harvard.edu https://astrumspace.info/tethysgeology
“Small Impact Crater Populations on Saturn's Moon Tethys and Implications for Source Impactors in the System”, via wiley.com https://astrumspace.info/impactcraters
“Plasma, plumes and rings: Saturn system dynamics as recorded in global color patterns on its midsize icy satellites”, via sciencedirect.com https://astrumspace.info/plasmatethys
“PacMan returns: An electron-generated thermal anomaly on Tethys”, via sciencedirect.com https://astrumspace.info/pacman
“A Pair of ‘Pac-Men’”, via nasa.gov https://astrumspace.info/pacmanpair


▀▀▀▀▀▀
Credits:Writer:
Jon McColganVideo
Editor: Nick Shishkin
Researcher: Edie Abrahams
Thumbnail Designer: Peter Sheppard
Channel Manager: Georgina Brenner
Executive Producer: Raquel Taylor
Creator of Astrum: Alex McColgan


With special thanks to:
NASA/ESO/ESA
#astrum #space #tethys
 
Strange radio pulses detected coming from ice in Antarctica

UNIVERSITY PARK, Pa. — A cosmic particle detector in Antarctica has emitted a series of bizarre signals that defy the current understanding of particle physics, according to an international research group that includes scientists from Penn State. The unusual radio pulses were detected by the Antarctic Impulsive Transient Antenna (ANITA) experiment, a range of instruments flown on balloons high above Antarctica that are designed to detect radio waves from cosmic rays hitting the atmosphere.

The goal of the experiment is to gain insight into distant cosmic events by analyzing signals that reach the Earth. Rather than reflecting off the ice, the signals — a form of radio waves — appeared to be coming from below the horizon, an orientation that cannot be explained by the current understanding of particle physics and may hint at new types of particles or interactions previously unknown to science, the team said.


Related paper:

 
Dark matter 'lampshades' dimming stars could solve one of the greatest scientific mysteries

Dark matter clumps could act as stellar lampshades, drifting between Earth and distant stars, dimming them by an almost imperceptible amount, a new study suggests.


Related paper:

 
Atomic Discrepancy Could Be Hint Of Fifth Force Of Nature

Scientists have found an intriguing discrepancy in the way electrons behave in different calcium atoms. The difference between the observations and actual theoretical calculation is subtle; however, the team believes the peculiar effect comes down to a single factor. Whether this factor is something known and missed, or something new, is yet to be determined, but researchers suggest it as tentative evidence for a fifth force of nature.

….

The origin of the discrepancy is unknown. It is possible that there are some Standard Model effects and that the calculations have not included them. A similar challenge to the Standard Model was solved just like that after years of data collection. Or it might be the first hint of a fifth force.

If it is a fifth force, it is very weak. It is also mediated by a boson particle that could be lighter than a neutrino or much heavier than a top quark. While that range is huge for a particle, it is the most stringent limit yet for such a hypothetical interaction.


Related paper:

 
There has always been talk of a Fifth Force of nature for as long as I have been interested in science, but what could it be? That is the Billion Dollar (Pound) question that I want answered Flyaway.
 
NASA’s Webb Observations Update Asteroid 2024 YR4’s Lunar Impact Odds

While asteroid 2024 YR4 is currently too distant to detect withtelescopes from Earth, NASA’s James Webb Space Telescope collected one more observation of the asteroid before it escaped from view in its orbit around the Sun.

With the additional data, experts from NASA’s Center for Near-Earth Object Studies at the agency’s Jet Propulsion Laboratory in Southern California further refined the asteroid’s orbit. The Webb data improved our knowledge of where the asteroid will be on Dec. 22, 2032, by nearly 20%. As a result, the asteroid’s probability of impacting the Moon has slightly increased from 3.8% to 4.3%.In the small chance that the asteroid were to impact, it would not alter the Moon’s orbit.

 
Let's just say that I do not want asteroid 2024 YR4 to crash into the Moon. The after affects would just be too horrendous to even think about.
 
Strange radio pulses detected coming from ice in Antarctica




Related paper:

Mysterious Lights over the Reich

There are two types of lights in the sky: the usual ones and the weird things.

“Possibly a naturally occurring phenomenon?”

-St. Elmo’s Fires. -Luminous phenomena generated during volcanic eruptions, earthquakes, large thunderstorms, tornadoes, large fires and nuclear explosions. -Luminous atmospheric phenomena recently discovered by satellite cameras: Sprites, Elves, dark blue luminous waterfalls and strange pulses of gamma rays that are emitted from the interior of the planet into space.-
 
AT2021uey: A planetary microlensing event outside the Galactic bulge

Abstract
We report the analysis of a planetary microlensing event AT2021uey. The event was observed outside the Galactic bulge and alerted both space-(Gaia) and ground-based (ZTF and ASAS-SN) surveys. From the observed data, we find that the lens system is located at a distance of ∼1 kpc and comprises an M-dwarf host star of about half a solar mass, orbited by a Jupiter-like planet beyond the snowline. The source star could be a metal-poor giant located in the halo according to the spectral analyses and modelling. Hence, AT2021uey is a unique example of the binary-lens event outside the bulge that is offered by a disc-halo lens-source combination.

 
Can you imagine what would happen to the earth and life on the planet if it was ever hit by a comet as vast as this one is!!!

Largest Oort Cloud Comet Ever Observed Reveals Its Secrets with ALMA’s Powerful Gaze

A team of astronomers has made a groundbreaking discovery by detecting molecular activity in comet C/2014 UN271 (Bernardinelli-Bernstein)—the largest and second most distantly active comet ever observed from the Oort Cloud. Using the powerful Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, researchers observed this giant comet while it was more than halfway to Neptune, at an astonishing distance of 16.6 times the distance between the Sun and Earth.

C/2014 UN271 is a true behemoth, measuring nearly 85 miles (140 km) across—more than 10 times the size of most known comets. Until now, little was known about how such cold, distant objects behave. The new observations revealed complex and evolving jets of carbon monoxide gas erupting from the comet’s nucleus, providing the first direct evidence of what drives its activity so far from the Sun.

 
‘Pinballs in a cosmic arcade’: New study suggests how wide-orbit planets form, supporting existence of Planet Nine

In the cold, dark outskirts of planetary systems far beyond the reach of the known planets, mysterious gas giants and planetary masses silently orbit their stars — sometimes thousands of astronomical units (AU) away. For years, scientists have puzzled over how these “wide-orbit” planets, including the elusive Planet Nine theorized in our own solar system, could have formed. Now, a team of astronomers may have finally found the answer.

In a new study published in Nature Astronomy, researchers from Rice University and the Planetary Science Institute used complex simulations to show that wide-orbit planets are not anomalies but rather natural by-products of a chaotic early phase in planetary system development. This phase occurs while stars are still packed tightly in their birth clusters and planets are jostling for space in turbulent, crowded systems.



The researchers also noted that if Planet Nine exists, it could be discovered soon after the Vera C. Rubin Observatory becomes fully operational. With its unparalleled ability to survey the sky in depth and detail, the observatory is expected to significantly advance the search for distant solar system objects, increasing the likelihood of either detecting Planet Nine or providing the evidence needed to rule out its existence.


Related paper:

 
BRIGHT NOVA LIGHTS UP LUPUS CONSTELLATION

Exciting news! On June 12th (June 12.9 UT), the All-Sky Automated Survey for Supernovae (ASAS-SN) discovered a new 8.7-magnitude stellar object in Lupus. Not long after, Yusuke Tampo, with the South African Astronomical Observatory (University of Cape Town), obtained a spectrum of the "new star" and identified it as a classical nova based on its spectral features and dramatic increase in brightness.

 
There appears to be a link of some sort between the level of atmospheric oxygen and the strength of Earth's magnetosphere, from Anton Petrov:


0:00 Discovery of a bizarre geological link
1:00 Magnetic field and the ozone layer
2:30 How we know how magnetosphere changed over time
3:30 Studying history of oxygen
4:50 Mystery correlation 330 million years ago
5:40 What's happening here? Potential explanations
8:20 Supercontinent link
9:30 Conclusions
10:30 Why this is important
 
The dead speak! Humanity has heard a mysterious signal, but the origin is not a broadcast from Star Wars’ Emperor Palpatine – it is from another seemingly defunct object. The NASA Relay 2 satellite, which worked for several years in the 1960s, appears to have sent a radio pulse back to Earth. Is the satellite back to life? Scientists think that something else might be going on.



On June 13, 2024, researchers at the Australian Square Kilometre Array Pathfinder spotted a peculiar emission in the sky. It was less than 30 nanoseconds, and analysis showed that it did not come from deep space but from orbit. The location of the signal suggested that the source was an old and defunct NASA satellite, which was certainly unexpected.



One possibility is that the satellite accumulated electrostatic charge, and it finally released a discharge. These ESDs (electrostatic discharges) have previously been seen by the Arecibo telescope, but on longer timescales.

There is also another possible explanation. A micrometeoroid,


Related paper linked to in the above article.
 
More detail to the above concerning Relay 2.

A nanosecond-duration radio pulse originating from the defunct Relay 2 satellite [Jun 16]

Hence, we suspect that the primary pulse is a bandwidth-limited impulse of true duration 3 ns or less and peak flux density of 3 MJy or more. Assuming the 3 MJy value over our 336 MHz bandwidth gives an incident power of 10[sup]−11[/sup] W m[sup]−2[/sup].

At a distance of 4500 km, this corresponds to a source electric field strength of 280 V m[sup]−1[/sup]; assuming 2 sr of emission from a surface (see §3), this implies a peak power output of 400 W (energy of 1.2 µ J and assuming a 3 ns intrinsic duration).
 
Just seen a report on the BBC News channel this morning about the Vera Rubin observatory, I cannot wait to see it being fully operational and making interesting new discoveries.

This is great news, after many years of delays for Chile's Large Synoptic Survey Telescope (now the Vera Rubin Observatory). I hope one of this wide-field-of-view telescope's first tasks will be to peer at the cone just beyond the speeding New Horizons probe, now 61 AU from us, and spot a suitable intercept target for the probe in that volume of space, if there's something there to spot. All other ground searches have failed, and the two space telescopes have too narrow a field of view to really help, Alan Stern told me. As I understand, Dr Stern and his team made enquiries to the Vera Rubin Observatory people. My fingers are crossed.
 
 
New study offers a double dose of ‘hot Jupiters’

Yale researchers show how the long-term evolution of binary star systems with two planets and two stars can produce something rare: double hot Jupiters


Paper linked to in the article.
 
Anton Petrov has another video about the largest comet discovered so far:

Hello and welcome! My name is Anton and in this video, we will talk about the biggest comet ever found - C/2014 UN271 (Bernardinelli–Bernstein)Links:

Hello and welcome! My name is Anton and in this video, we will talk about the biggest comet ever found - C/2014 UN271 (Bernardinelli–Bernstein)
Links:
https://iopscience.iop.org/article/10...https://www.youtube.com/redirect?ev...rticle/10.3847/2041-8213/add526&v=EHeuDzJhiy4
Asteroid Antonpetrov:
https://www.youtube.com/watch?v=laVs35QhiAo
• Holy Cow, Someone Named a Minor Planet Aft... https://www.youtube.com/watch?v=laVs35QhiAo
#comet #solarsystem #c2014un271



1:00 Initial discovery and why it was strange
4:10 Outbursts and emissions
5:05 2.5 million years?!
5:45 Closest approach and observations
6:20 New observations and discoveries - huge size
7:30 Dark and strange properties
8:20 How it will change
9:20 Initial explanations and what's next?
 

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