SubNeptune planet K2-18b shows methane and dimethyl sulfide

  • B
  • Thread starter DaveC426913
  • Start date
  • Tags
    Exoplanet
  • #1
DaveC426913
Gold Member
22,497
6,168
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
  • #2
Very thrilling and exciting! :smile:
 
  • Like
Likes pinball1970
  • #3
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.
 
  • #4
Stinky.
 
  • Haha
Likes DennisN

1. What is a SubNeptune planet?

A SubNeptune planet is a type of exoplanet that is larger than Earth but smaller than Neptune. It typically has a rocky core and a thick atmosphere, similar to Neptune.

2. What is the significance of methane and dimethyl sulfide on planet K2-18b?

Methane and dimethyl sulfide are both gases that can be produced by living organisms. The presence of these gases on K2-18b suggests that the planet may have the potential to support life.

3. How was the presence of methane and dimethyl sulfide detected on planet K2-18b?

The presence of these gases was detected using spectroscopy, which involves analyzing the light that passes through a planet's atmosphere. Each gas has a unique spectral signature that can be detected and used to identify its presence.

4. Is planet K2-18b the only SubNeptune planet that has been found to have methane and dimethyl sulfide?

No, there have been other SubNeptune planets discovered with these gases in their atmospheres. However, K2-18b is the first to have both methane and dimethyl sulfide detected.

5. What does the discovery of methane and dimethyl sulfide on planet K2-18b mean for the search for extraterrestrial life?

The discovery of these gases on K2-18b is significant because it adds to the growing list of potentially habitable exoplanets. This discovery also highlights the importance of studying the atmospheres of exoplanets in the search for life beyond Earth.

Hot Threads

Recent Insights

Back
Top