Astronomers have directed JWST to examine the atmosphere of an exoplanet called K2-18 b, which orbits a cool dwarf star about 120 light-years from Earth. The planet is 8.6 times as massive as Earth, and the observations have revealed methane and carbon dioxide in its atmosphere. This opens up the intriguing possibility that this exoplanet is an example of a theorized 'hycean world,' a planet with a hydrogen-rich atmosphere and a water ocean covering its surface that extends deeper than anything we have on Earth.
Despite its great oceans, Earth is not really an ocean world. It has less water than icy moons such as, a relatively thin nitrogen-rich atmosphere, and vast continents that rise above sea level. A true ocean world would have no continents, a warm sea hundreds of kilometers deep, and a thick hydrogen and water-rich atmosphere. They are known as hydrogen-ocean planets or hycean worlds. While we’ve long thought they exist, the James Webb Space Telescope may now have found one.
Hycean planets are thought to be common in the super-Earth range of mass and size. Super-Earths are often found orbiting red dwarf stars, which are known to have tremendous solar flares. A planet orbiting in a red dwarf’s warm habitable zone risks being stripped of its atmosphere.
New observations by JWST suggest that they do. The planet in question is K2-18 b. It has a mass nearly 9 times that of Earth, and a radius almost 3 times that of Earth. Its orbit is in the habitable zone of a red dwarf star just 120 light-years from Earth.
United States Latest News, United States Headlines
Similar News:You can also read news stories similar to this one that we have collected from other news sources.
Newly discovered green comet to sweep past Earth next weekIt will not be seen again for 400 years.
Read more »
- Earth Friendly Gardening and Landscaping SessionsCultivate - Earth Friendly Gardening and Landscaping Sessions Bexar County Master Gardeners (BCMG) is hosting its free online biannual gardening workshop September 8-9 from 9am to 1pm. Sign-up for classes is available at bexarmg.org. Workshops range from watering practices to plant selection and maintenance. These free sessions are led by Texas AgriLife Extension and BCMG experts. With such extreme temperatures, it is a challenge to know what to plant and how much to water. Attendees will be able to implement the up-to-date recommendations in their fall landscapes and ask questions of the presenters.
Read more »
Mimicking Mother Earth: Crafting an Artificial Carbon Cycle Beyond Our PlanetThe artificial carbon cycle, inspired by Earth's natural process, presents a solution to supplying resources for space missions. Artificial photosynthesis through photocatalytic CO2 conversion is a promising approach, but efficiency improvements are needed. Currently, space missions mainly rely o
Read more »
Astronaut wields new space camera to see lightning strikes on EarthIt's a flashy follow-up to a 2015 lightning study.
Read more »
The Closest Black Holes to Earth are Probably Hidden in This Nearby Star ClusterThe Hyades cluster is the closest open star cluster to Earth, located at a distance of about 150 light-years. Although black holes haven't been directly seen in the cluster, it's an excellent place to search for them because the largest stars would have detonated as supernovae and collapsed in neutron stars and black holes. Astronomers have simulated the motions of stars in the cluster with black holes lurking around and then compared them to the motions of the actual stars. They only matched with the presence of black holes near the center of the cluster.
Read more »
This Week @NASA: SpaceX Crew-6 Splashdown, Psyche Spacecraft Hitchhiker, Ancient Life on EarthNASA’s SpaceX Crew-6 mission safely returns to Earth … The tech demo hitching a ride on NASA’s Psyche spacecraft … And studying ancient life on Earth to better understand Mars … A few of the stories to tell you about – This Week at NASA! https://youtu.be/W3XPrUN7RYk NASA’s SpaceX Crew
Read more »