TRAPPIST-1 tagged posts

A low carbon abundance in planetary atmospheres could be a signature of habitability. Scientists at MIT, the University of Birmingham, and elsewhere say that astronomers’ best chance of finding liquid water, and even life on other planets, is to look for the absence, rather than the presence, of a chemical feature in their atmospheres.

The researchers propose that if a terrestrial planet has substantially less CO2 in its atmosphere compared to other planets in the same system, it could be a sign of liquid water — and possibly life — on that planet’s surf...

Scientists at UC Riverside are suggesting something is missing from the typical roster of chemicals that astrobiologists use to search for life on planets around other stars — laughing gas.

Chemical compounds in a planet’s atmosphere that could indicate life, called biosignatures, typically include gases found in abundance in Earth’s atmosphere today.

“There’s been a lot of thought put into oxygen and methane as biosignatures. Fewer researchers have seriously considered nitrous oxide, but we think that may be a mistake,” said Eddie Schwieterman, an astrobiologist in UCR’s Department of Earth and Planetary Sciences.

This conclusion, and the modeling work that led to it,...

The small, cool M dwarf star TRAPPIST-1 and its seven worlds. New research from the University of Washington speculates on possible climates of these worlds and how they may have evolved.
Credit: NASA

Not all stars are like the sun, so not all planetary systems can be studied with the same expectations. New research from a University of Washington-led team of astronomers gives updated climate models for the seven planets around the star TRAPPIST-1. The work also could help astronomers more effectively study planets around stars unlike our sun, and better use the limited, expensive resources of the James Webb Space Telescope, now expected to launch in 2021.

“We are modeling unfamiliar atmospheres, not just assuming that the things we see in the solar system will look the same way around anot...

This artist’s impression shows several of the planets orbiting the ultra-cool red dwarf star TRAPPIST-1. New observations, when combined with very sophisticated analysis, have now yielded good estimates of the densities of all seven of the Earth-sized planets and suggest that they are rich in volatile materials, probably water. Credit: ESO/M. Kornmesser

A new study has found that planets orbiting the star TRAPPIST-1 are made mostly of rock, and some could hold more H2O than Earth. The planets’ densities suggest that some of them could have up to 5% of their mass in the form of water. The hotter planets closest to their parent star are likely to have dense steamy atmospheres and the more distant ones probably have icy surfaces...