NASA is finalizing the final preparations for the launch of its Transiting Exoplanet Survey Satellite (TESS) that will launch on April 16 and travel to undiscovered worlds around nearby stars in an effort to provide targets for future study of finding life in space.

TESS will launch from Space Launch Complex 40 in Cape Canaveral Air Force Station in Florida and with a gravitational assist from the moon, will settle into a 13.7-day orbit around Earth. Then after 60 days, following tests of its instruments the satellite will begin an initial two-year mission.

“One of the biggest questions in exoplanet exploration is: If an astronomer finds a planet in a star’s habitable zone, will it be interesting from a biologist's point of view?” says George Ricker, TESS principal investigator at the Massachusetts Institute of Technology (MIT) Kavli Institute for Astrophysics and Space Research in Cambridge, which is leading the mission. “We expect TESS will discover a number of planets whose atmospheric compositions, which hold potential clues to the presence of life, could be precisely measured by future observers.”

An artist rendering of the TESS satellite. Source: NASAAn artist rendering of the TESS satellite. Source: NASATESS contains four wide-field cameras that will give the satellite a field-of-view that covers 85 percent of the entire sky, which will be divided into 26 sectors that TESS will observe one by one. The first year of observations will map the 13 sectors encompassing the southern sky and the second year will map the 13 sectors of the northern sky.

TESS will search for a phenomenon known as a transit, where a planet passes in front of its star, causing a periodic and regular dip in the star’s brightness. The Kepler spacecraft used the same method to spot more than 2,600 confirmed exoplanets, most of them orbiting faint stars 300 to 3,000 light-years away.

The satellite will concentrate on stars less than 300 light-years away and 30 to 100 times brighter than Kepler’s targets. The brightness of these target stars will allow researchers to use spectroscopy, or the study of the absorption and emission of light, to determine a planet’s mass, density and atmospheric composition.

“TESS is opening a door for a whole new kind of study,” says Stephen Rinehart, TESS project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, which manages the mission. “We’re going to be able to study individual planets and start talking about the differences between planets. The targets TESS finds are going to be fantastic subjects for research for decades to come. It’s the beginning of a new era of exoplanet research.”

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