November Starcharts and research papers

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Edwin Rod

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Nov 4, 2024, 3:44:37 PM11/4/24
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Hi Folks

A few interesting ones this month to read, two interesting news items out today on Planets around red dwarf stars as well. The Planet around Barnards star is an amazing discovery and I’m looking forward to studying that one further.

 

 

Rocky planets orbiting small stars could have stable atmospheres needed to support life

https://www.washington.edu/news/2024/10/23/rocky-planets-orbiting-small-stars-could-have-stable-atmospheres-needed-to-support-life

 

 

 

Constraining Ocean and Ice Shell Thickness on Miranda from Surface Geological Structures and Stress Modeling

https://iopscience.iop.org/article/10.3847/PSJ/ad77d7

 

 

Scientists discover planet orbiting closest single star to our Sun

https://www.eso.org/public/archives/releases/sciencepapers/eso2414/eso2414a.pdf

 

 

 

What doesn’t kill Gaia makes her stronger

https://arxiv.org/abs/2405.05091

 

 

 

New Transient Co-orbital Asteroids of Venus

https://iopscience.iop.org/article/10.3847/2515-5172/ad7261

 

 

Searching for GEMS: TOI-6383Ab

https://arxiv.org/abs/2409.16889

 

 

 

A Radio Technosignature Search of TRAPPIST-1

https://arxiv.org/abs/2409.08313

 

 

WST/NIRISS Reveals the Water-rich "Steam World" Atmosphere of GJ 9827 d

https://iopscience.iop.org/article/10.3847/2041-8213/ad6f00

 

 

Multi-messenger Probes of Supermassive Black Hole Spin Evolution

https://arxiv.org/abs/2410.07477

 

 

 

Dietary tendencies of the Early Jurassic pterosaurs

https://www.tandfonline.com/doi/full/10.1080/02724634.2024.2403577

 

 

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Interesting News items

 

 

Scientists discover planet orbiting closest single star to our Sun

https://www.eso.org/public/news/eso2414/

 

 

Barnard’s Star Has a Confirmed Planet — At Last!

https://skyandtelescope.org/astronomy-news/barnards-star-has-a-confirmed-planet-at-last

 

 

 

Were just at the right time to observe the Rings

https://www.astronomy.com/science/how-long-will-saturns-rings-last-before-they-disappear

 

 

 

New Kuiper Belt objects lurk farther away than we ever thought

https://arstechnica.com/science/2024/10/new-kuiper-belt-objects-lurk-farther-away-than-we-ever-thought/

 

 

Getting closer to the explanation of how giant planets can form around M-dwarfs

https://www.dlr.de/en/pf/about-us/departments/extrasolar-planets-and-atmospheres/news-from-our-department-epa/getting-closer-to-the-explanation-of-how-giant-planets-can-form-around-m-dwarfs

 

 

Ocean on Miranda?

Uranus’ Moon Miranda May Have an Ocean Beneath Its Surface, New Study Finds




 








L 98-59.
L 98-59 is a small, red dwarf star some 34.5 light years away from the solar system within the faint, far southern constellation of Volans the Flying Fish.
L 98-59 Mass is about 27.3% that of our Sun or about 90,894 times that of the Earth. Our Sun has a mass of 332,946 times that of the Earth. The diameter only 30.3% that of our Sun or 421,594 KM / 261,966 miles or 33 times that of the Earth where as our Sun has a diameter of 1,391,400 KM / 864,576 miles or 109 times that of the Earth. L 98-59 has a spectrum of M3 where as our Sun's is G2. The average surface temperature of L 98-59 is 3,157 Celsius, our Sun's is 5,499 Celsius. L 98-58 rotates on it's axis once every 80.9 days, quite slow for a relatively young star. For our Sun the rotation period is 25.6 days at the equator & 35.5 days at the poles. L 98-59 is about 800 million years old verses 4.6 billion years old for the Sun.
L 98-59 has four known planets and a fifth very highly likely one. This update concerns the third planet out from the star or L 98-59d.
L 98-59d is deemed a super Earth. It is about 1.6 times more massive than the Earth and about 1.5 times wider than the Earth. This shows that the density is a little lower than Earth's but it is a terrestrial planet, mostly rock and metal like Earth. L 98-59d orbits it's red dwarf Sun at a mean distance of only 7.29 million KM / 4.529 million miles once every 7.5 days.
L 98-59d has been found to have a very thin atmosphere rich in hydrogen / H, but with a significant amount of sulphur dioxide / SO2. Hydrogen Sulphide / H2S is also present. The density of this atmosphere at the surface, at the very most is about 25 mb or 1/40th of Earth's at sea level.
However the Sulphur enrichment is interesting, possibly a planet dominated by volcanoes, maybe a bit like Venus or Jupiter's large volcanic moon Io. Unlike Venus, no thick atmosphere. The average global temperature is about 137 Celsius / 277 Fahrenheit or 410 Kelvin, so is quite warm. However finer details like axial tilt or rotation period are lacking, so it could be very hot on one side and extremely cold on the other like Mercury, etc.
Both the Hubble Space Telescope & the James Webb Space Telescope have observed L 98-59 and have gained some detail on the parent star and known four planets.
Our Sun would appear as a third magnitude star in front of the constellation of Draco the Dragon from the L 98-59 system.
The HST was launched from the Space Shuttle Discovery on mission STS-31 Discovery on: Tuesday 24th April 1990 from the Kennedy Space Centre, Florida, USA.
The JWST was launched on Christmas Day 2021 on board an Ariane 5 booster from the Kourou Spaceport, French Guiana. Flight: VA 254.
Text: Andrew R Brown.
NASA/ESA/STSCI. Hubble Space Telescope.
NASA/ESA/CSA/STSCI. James Webb Space Telescope.



All charts 2411.pdf
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