A possible sign of life had been found on another world, which got a lot of attention last fall. The proof came from the James Webb Space Telescope, which found a chemical called dimethyl sulfide on a planet called K2-18b that is not our own.
Plants called phytoplankton in the seas make DMS on Earth.
What Signs Of Life?
Did NASA find proof that there is life in other parts of the universe? A new study that came out this week in Astrophysical Journal Letters says it’s not likely. It says there isn’t a DMS around K2-18b and the discovery that came out last fall was wrong.
Even though some people didn’t like the first discovery, news sites have kept running the same stories from the fall about NASA finding proof of life. A lot of news outlets have false headlines because they haven’t even read the last study, let alone the newest one.
Read More: Under the crust of the Earth, scientists have found a huge pool with more water than on the surface.
What’s really going on is this?
Interesting K2-18b is an interesting exoplanet, which is a planet that follows a star other than our own. This one is 120 light-years away and goes around a cool red dwarf star. It can be seen in the night sky in the constellation Leo.
“Super Earth” and “sub-Neptune” describe this world, which is 8.6 times as heavy as Earth. It’s bigger than Earth but smaller than Neptune. These kinds of worlds seem to be the most common in the Milky Way, but we don’t have any like them in our space.
The Kepler Space Telescope of NASA found K2-18b in 2015. The Hubble Space Telescope found proof of water vapor in the atmosphere in 2019.
Read More: Astronomers have found Super Earth, but there’s something weird about it.
Hycean World
“Hycean World” K2-18b is thought to be the model “Hycean” world. Its high levels of methane and carbon dioxide and low levels of ammonia hint that there may be an ocean below a hydrogen-rich atmosphere.
DMS is thought to be a biosignature, which means it shows that there was or is life on K2-18b. The planet may also be livable because it has an ocean, atmosphere, and about the same amount of sunlight as Earth.
“This planet almost gets the same amount of sunlight as Earth.” “K2-18b has a temperature close to Earth’s if the atmosphere is taken out, which is also a great place to find life,” said Shang-Min Tsai, project scientist at the University of California, Riverside and author of the study.
Streamed Starlight
Planetary scientists know a lot about exoplanets from sunlight that has been filtered through their atmospheres. The results show patterns in molecules. Tsai said, “The DMS signal from the Webb telescope wasn’t very strong, and it only showed up in certain ways when we looked at the data.” What seemed like a hint about DMS made us wonder if we could be sure.
Researchers came to the conclusion that DMS is not likely to be on K2-18b by using computer models of the physics and chemistry of DMS and the planet’s hydrogen-based atmosphere. “The signal strongly overlaps with methane, and we don’t think this instrument can separate DMS from methane,” Tsai said. It was found that there was more DMS than there is on Earth, but it wasn’t thought to be accurate until it got to about 20 times the amount that is on Earth.
I wish you clear skies and big eyes.
