B SubNeptune planet K2-18b shows methane and dimethyl sulfide

  • B
  • Thread starter Thread starter DaveC426913
  • Start date Start date
  • Tags Tags
    Exoplanet
AI Thread Summary
NASA's James Webb Space Telescope has detected methane and carbon dioxide in the atmosphere of the exoplanet K2-18b, which is significantly more massive than Earth. The findings suggest the possibility of a water ocean beneath its hydrogen-rich atmosphere, as indicated by the abundance of these gases and a lack of ammonia. Additionally, there is a potential detection of dimethyl sulfide (DMS), a molecule typically produced by life on Earth. The discussion also raises questions about K2-18b's orbital characteristics, particularly regarding tidal locking due to its distance from its host star. Overall, these discoveries open up exciting possibilities for understanding the planet's environment and potential habitability.
DaveC426913
Gold Member
Messages
23,861
Reaction score
7,900
TL;DR Summary
SubNeptune planet 120ly away shows presence of molecules associated with life
"A new investigation with NASA’s James Webb Space Telescope into K2-18 b, an exoplanet 8.6 times as massive as Earth, has revealed the presence of carbon-bearing molecules including methane and carbon dioxide.
...
The abundance of methane and carbon dioxide, and shortage of ammonia, support the hypothesis that there may be a water ocean underneath a hydrogen-rich atmosphere in K2-18 b. These initial Webb observations also provided a possible detection of a molecule called dimethyl sulfide (DMS). On Earth, this is only produced by life. The bulk of the DMS in Earth’s atmosphere is emitted from phytoplankton in marine environments."

https://www.nasa.gov/goddard/2023/webb-discovers-methane-carbon-dioxide-in-atmosphere-of-k2-18b
 
  • Informative
  • Like
Likes pinball1970, DennisN, Tom.G and 2 others
Astronomy news on Phys.org
Very thrilling and exciting! :smile:
 
  • Like
Likes pinball1970
Raises an eyebrow, a la Mr. Spock. "Fascinating!"Seriously though, do we have enough data on the exoplanet's mass, it's host star's mass and their separation to know whether K2-18b is tidally locked?

From popular science articles I've read (Sky & Telescope, I think) tidal locking is a problem for exoplanets orbiting red dwarves because these systems tend to be far more compact than our, more extended retinue of planets.

https://en.wikipedia.org/wiki/TRAPPIST-1

Several of the planets in the Trappist-1 system are expected to be tidally locked and I note that the outermost has an orbital period of 18.772 days. The cited period for K2-18b is 32.940 days. I wonder if that's sufficiently distant to place it outside of the tidal locking zone?

Any thoughts?Thank you,

Cerenkov.
 
Stinky.
 
Today at about 4:30 am I saw the conjunction of Venus and Jupiter, where they were about the width of the full moon, or one half degree apart. Did anyone else see it? Edit: The moon is 2,200 miles in diameter and at a distance of 240,000 miles. Thereby it subtends an angle in radians of 2,200/240,000=.01 (approximately). With pi radians being 180 degrees, one radian is 57.3 degrees, so that .01 radians is about .50 degrees (angle subtended by the moon). (.57 to be more exact, but with...
This thread is dedicated to the beauty and awesomeness of our Universe. If you feel like it, please share video clips and photos (or nice animations) of space and objects in space in this thread. Your posts, clips and photos may by all means include scientific information; that does not make it less beautiful to me (n.b. the posts must of course comply with the PF guidelines, i.e. regarding science, only mainstream science is allowed, fringe/pseudoscience is not allowed). n.b. I start this...

Similar threads

Back
Top