Water worlds? Updated masses for TRAPPIST-1 planets

Artist’s conception of some of the planets in the TRAPPIST-1 planetary system. Image Credit: ESO/M. Kornmesser/N. Risinger (skysurvey.org)

There is an interesting new paper out about the seven near-Earth-sized exoplanets orbiting the star TRAPPIST-1. According to the study, four of the planets may be true water worlds, although just what form those may take isn’t clear. All seven planets are close in size to the Earth, with some of them in the star’s habitable zone, where temperatures could allow liquid water on rocky surfaces.

Read MoreWater worlds? Updated masses for TRAPPIST-1 planets

NASA’s Kepler Space Telescope continues observations of TRAPPIST-1 planetary system

Artist’s conception of some of the planets in the TRAPPIST-1 planetary system. Image by ESO/M. Kornmesser/N. Risinger (skysurvey.org)

The seven Earth-sized exoplanets orbiting the star TRAPPIST-1 generated a lot of excitement when their discovery was announced last month. This is the largest collection of Earth-sized worlds in one planetary system found so far, and some of them are well within the star’s “habitable zone” where temperatures could allow liquid water to exist on their surfaces. Little else is known about the actual conditions on these planets so far, but NASA’s Kepler Space Telescope has also been observing TRAPPIST-1 in recent weeks.

Read MoreNASA’s Kepler Space Telescope continues observations of TRAPPIST-1 planetary system

Could the TRAPPIST-1 planetary system be home to alien life?

Artist’s conception of the TRAPPIST-1 planetary system as seen from one of the seven Earth-sized planets. Image Credit: ESO/M. Kornmesser

The discovery of seven Earth-sized planets orbiting the star TRAPPIST-1 generated a lot of excitement last week. Earth-sized planets have been found before, among the thousands of exoplanets discovered so far by astronomers, but this is the first time that so many have been detected in one planetary system. As of now, astronomers are limited in how much they can learn about these new worlds, but the James Webb Space Telescope, the upcoming successor to Hubble due to launch in 2018, will be able to gather more data and analyze whatever atmospheres these planets have, perhaps bringing us closer to finding another habitable world.

Read MoreCould the TRAPPIST-1 planetary system be home to alien life?

NASA’s Spitzer Space Telescope discovers seven Earth-sized worlds orbiting nearby star

Artist’s conception of standing on the surface of exoplanet TRAPPIST-1f. Image Credit: NASA/JPL-Caltech

The search for exoplanets – planets orbiting other stars – has been one of the most exciting developments in astronomy and space science in recent years. The first couple exoplanets were found in 1992, and now over 3,400 have been confirmed, with over 5,000 additional candidates. Some of these are smaller rocky worlds similar in size to Earth, bringing scientists close to finding “Earth 2.0” – another planet with water and, perhaps, life. Yesterday, NASA announced another key discovery, bringing us even closer to finding another living world – a star with not just one or two Earth-sized planets orbiting it, but seven. Three of those planets are in the star’s habitable zone, where, depending upon other surface conditions, lakes or oceans of liquid water could exist.

Read MoreNASA’s Spitzer Space Telescope discovers seven Earth-sized worlds orbiting nearby star