Europe launches mission to study distant planets

A European telescope designed to help characterize planets orbiting stars far from the Sun launched to space Wednesday.

Why it matters: Astronomers are on the hunt for another world like our Earth, and this new mission — called CHaracterising ExOPlanet Satellite (Cheops) — could help them figure out if there are habitable worlds somewhere out there.

Details: After it begins science observations, Cheops will perform follow-up observations on hundreds of planets outside our solar system — known as exoplanets — that were discovered by other missions.

• The space telescope will watch as these worlds pass in front of their stars, blocking out a small amount of light and allowing Cheops to get a sense of their sizes, according to the European Space Agency (ESA).
• Using this data along with other information already gathered about these worlds will allow scientists to paint a more complete portrait of the exoplanets and figure out if some might be like Earth.
• According to ESA, it's even possible that Cheops might be able to study the atmospheres of some of these exoplanets as well.

“There are so many interesting exoplanets and we will be following up on several hundreds of them, focusing in particular on the smaller planets in the size range between Earth and Neptune. They seem to be the commonly found planets in our Milky Way galaxy, yet we do not know much about them."

The big picture: So far, researchers have found more than 4,000 exoplanets total.

• Scientists still don't have the tools to be able to definitively say whether a planet is or is not habitable like Earth, but spacecraft like Cheops will help make that hunt for another Earth a bit easier in the long run.

Go deeper: The most distant world ever observed from close range has an official name