New insights into the atmosphere and star of an exoplanet

Astronomers led by a team at Université de Montréal has made important progress in understanding the intriguing TRAPPIST-1 exoplanetary system, which was first discovered in 2016 amid speculation it could someday provide a place for humans to live.

Not only does the new research shed light on the nature of TRAPPIST-1 b, the exoplanet orbiting closest to the system’s star, it has also shown the importance of parent stars when studying exoplanets.

Published in Astrophysical Journal Letters, the findings by astronomers at UdeM's Trottier Institute for Research on Exoplanets (iREx) and colleagues in Canada, the U.K. and U.S. shed light on the complex interplay between stellar activity and exoplanet characteristics.



The astronomers' key finding was just how significant stellar activity and contamination are when trying to determine the nature of an exoplanet. Stellar contamination refers to the influence of the star's own features, such as dark spots and bright faculae, on the measurements of the exoplanet's atmosphere.

The team found compelling evidence that stellar contamination plays a crucial role in shaping the transmission spectra of TRAPPIST-1 b and, likely, the other planets in the system. The central star’s activity can create “ghost signals” that may fool the observer into thinking they have detected a particular molecule in the exoplanet’s atmosphere.


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Jupiter Mass Binary Objects in the Trapezium Cluster
Authors: Samuel G Pearson, Mark J McCaughrean

Abstract

A key outstanding question in star and planet formation is how far the initial mass function of stars and sub-stellar objects extends, and whether or not there is a cut- off at the very lowest masses. Isolated objects in the planetary-mass domain below 13 Jupiter masses, where not even deuterium can fuse, are very challenging to observe as these objects are inherently faint. Nearby star-forming regions provide the best opportunity to search for them though: while they are young, they are still relatively warm and luminous at infrared wavelengths. Previous surveys have discovered a handful of such sources down to 3–5 Jupiter masses, around the minimum mass limit established for formation via the fragmentation of molecular clouds, but does the mass function extend further? In a new James Webb Space Telescope near-infrared survey of the inner Orion Nebula and Trapezium Cluster, we have discovered and characterised a sample of 540 planetary-mass candidates with masses down to 0.6 Jupiter masses, demonstrating that there is indeed no sharp cut-off in the mass function. Furthermore, we find that 9% of the planetary- mass objects are in wide binaries, a result that is highly unexpected and which challenges current theories of both star and planet formation

 
The James Webb Space Telescope has helped demystify the strange 2009 observation of a giant star about 25 times more massive than the sun that appeared to disappear from existence.

In 2009, astronomers observed what they believed was a giant star about 25 times more massive than the sun, increasing its brightness to a million suns as if it was about to explode into a supernova, then suddenly fading instead of exploding.



The yet-to-be peer-reviewed research reports not one remnant object in the position of the star, but three, making the failed supernova model less likely.

Researchers now suspect that the 2009 brightening observation was rather likely caused by two stars merging.

The brightening they say may have been due to two stars merging, which then faded.

Researchers say the failed supernova model can still not be completely ruled out.


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NASA’s Webb Finds Carbon Source on Surface of Jupiter’s Moon Europa

Jupiter’s moon Europa is one of a handful of worlds in our solar system that could potentially harbor conditions suitable for life. Previous research has shown that beneath its water-ice crust lies a salty ocean of liquid water with a rocky seafloor. However, planetary scientists had not confirmed if that ocean contained the chemicals needed for life, particularly carbon.


ALL THESE WORLDS ARE YOURS EXCEPT EUROPA. ATTEMPT NO LANDING THERE.
 
View: https://flic.kr/p/2p8QRa2


NASA’s Webb Captures an Ethereal View of NGC 346

One of the greatest strengths of NASA’s James Webb Space Telescope is its ability to give astronomers detailed views of areas where new stars are being born. The latest example, showcased here in a new image from Webb’s Mid-Infrared Instrument (MIRI), is NGC 346 – the brightest and largest star-forming region in the Small Magellanic Cloud.

The Small Magellanic Cloud (SMC) is a satellite galaxy of the Milky Way, visible to the unaided eye in the southern constellation Tucana. This small companion galaxy is more primeval than the Milky Way in that it possesses fewer heavy elements, which are forged in stars through nuclear fusion and supernova explosions, compared to our own galaxy.

Since cosmic dust is formed from heavy elements like silicon and oxygen, scientists expected the SMC to lack significant amounts of dust. However the new MIRI image, as well as a previous image of NGC 346 from Webb’s Near-Infrared Camera released in January, show ample dust within this region.

In this representative-color image, blue tendrils trace emission from material that includes dusty silicates and sooty chemical molecules known as polycyclic aromatic hydrocarbons, or PAHs. More diffuse red emission shines from warm dust heated by the brightest and most massive stars in the heart of the region. An arc at the center left may be a reflection of light from the star near the arc’s center. (Similar, fainter arcs appear associated with stars at lower left and upper right.) Lastly, bright patches and filaments mark areas with abundant numbers of protostars. The research team looked for the reddest stars, and found 1,001 pinpoint sources of light, most of them young stars still embedded in their dusty cocoons.

Image credit: NASA, ESA, CSA, STScI, N. Habel (JPL). Image Processing: P. Kavanagh (Maynooth University)
 
Researchers using NASA's James Webb Space Telescope have detected evidence for quartz nanocrystals in the high-altitude clouds of WASP-17 b, a hot Jupiter exoplanet 1,300 light-years from Earth.

The detection, which was uniquely possible with MIRI (Webb's Mid-Infrared Instrument), marks the first time that silica (SiO2) particles have been spotted in an exoplanet atmosphere.


Related paper:

 
I looked up Tellurium's atomic number (52) so it's a medium atomic number meaning it should be formed regularly in Type-II core-collapse supernovae.
 
View: https://twitter.com/haygenwarren/status/1718733454332797197


Using Webb, scientists have discovered a high-speed jet stream at Jupiter’s equator. Webb first observed the jet stream in July 2022, and its images allowed scientists to measure winds up to 515 kilometers per hour.

Martijn Luinstra with the details ⬇️

 
View: https://twitter.com/nasawebb/status/1718993338362401229


It’s Monday. Feeling crabby?

6,500 light-years away lies the Crab Nebula, the remains of an exploded star. While it is a well-studied target, Webb’s infrared sensitivity and resolution offer new clues into the makeup and origins of this nebula:


A crab collab

On the left is @NASAHubble’s 2005 view of the Crab Nebula, taken in optical light. On the right is Webb’s new look, taken in infrared light. By combining observations of this target, astronomers can deepen their understanding of the star life cycle.

Related video:

View: https://youtu.be/8dRQqgg2eTc?si=SIsMjuUA-H1kax8i
 
The James Webb Space Telescope (JWST) has discovered that nearly all of the universe's earliest galaxies were filled with dazzling gas clouds that blazed brighter than the emerging stars within them — and it could help solve a mystery that threatens to break cosmology.



Now, astronomers have found a possible answer: a large group of 12 billion-year-old galaxies almost 90% of which were wreathed in bright gas that — after being ignited by light from the surrounding stars — triggered intense bursts of star formation as the gas cooled. The new research has been accepted for publication in The Astrophysical Journal.

 
Nasa’s James Webb space telescope has revealed a planet where specks of sand fall as rain, in groundbreaking observations.
The planet, Wasp-107b, lies 200 light years away in the Virgo constellation and had already caught the attention of astronomers because it is very large but very light, earning it the nickname the “candy floss” planet. The latest observations give an unprecedented glimpse of a strange and exotic world beyond our solar system that features silicate sand clouds and rain, scorching temperatures, raging winds and the distinct burnt-matches scent of sulphur dioxide.


Related paper:

 





Pls no bulli if I sound like a dunce but isnt this partly describing quasars? Other aspect of brightness has to do with the very large and active central black hole heating up the gas as well?
 
I suppose that will include observations of moons with prospects of life a bit like Saturn's two moons Titan and Enceladus and not forgeting Jupiter's moon Europa?
 
I wonder where NASA will put the model? Any Ideas. Cape Canaveral? Since the JWST was launched from there.
 
I wonder where NASA will put the model? Any Ideas. Cape Canaveral? Since the JWST was launched from there.
Right now, it's here:
 

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