SPACE

In 2017, astronomers discovered seven planets orbiting a star dubbed TRAP­PIST-1, a faint red dwarf 40 light-years from Earth and only 9 percent as bright as our sun. The Earth-like qualities of these planets made headlines: they are of similar sizes to our planet, and their orbits fall within TRAPPIST-1’s habitable zone — two characteristics that scientists think are important for life to exist on a planet. Researchers now report that the TRAPPIST-1 planets have even more traits in common with Earth: they are likely rocky, and they may have surface water that exists as liquid, ice and vapor.

Two upcoming missions will provide the first systematic approach to searching the atmospheres of exoplanets for signs of life — and they could find it in the next several decades.

Before NASA’s Cassini mission, which ended in 2017 after 13 years orbiting Saturn, little was known about the surface of the planet’s largest moon, Titan, as most of its features lie obscured under a dense, opaque atmosphere composed mainly of nitrogen gas. However, thanks to special filters that enabled Cassini’s cameras to see through the haze, the spacecraft captured high-resolution images of about 9 percent of Titan’s surface, with 25 to 30 percent of the moon imaged in lower resolution. Researchers have now used an algorithm to interpolate the remainder of the moon’s surface and create the most complete global topographic map of Titan yet.

With two rovers patrolling the surface of Mars, six spacecraft orbiting above it, and scientists here on Earth studying the Red Planet from afar, new findings are announced often. Here are a few of the latest updates.