On April 18 of this year, NASA launched a $337 million spacecraft—on the back of a SpaceX Falcon 9 rocket—from the Cape Canaveral Air Force Station to search for planets outside of our solar system. According to the agency, the Transiting Exoplanet Survey Satellite (TESS) started its official scientific observations on July 25. Now in its final 13.5-day orbit around the Earth, the craft has completed the checkout of all of its cameras.
NASA head of Astrophysics, Paul Hertz, said in a statement, “I’m thrilled that our new planet hunter mission is ready to start scouring our solar system’s neighborhood for new worlds.”
This is notable because NASA had originally said, at the time of launch, that TESS would not begin its first scientific operations for at least 60 days after the launch. Obviously, the commissioning has taken more than a month longer than originally expected—and NASA has not explained why—even though the spacecraft appears to be in good health.
Nonetheless, TESS will set out to search for exoplanets by searching for them as they pass in front of—in transit of—the stars they orbit. Keep in mind that our yellow sun is the “star” around which our planetary system orbits. To discover them, TESS looks for very small and periodic dips in the brightness of their stars, which the craft observes on its camera. NASA the expects, though, that TESS will find several thousand exoplanets over the course of this mission, particularly focusing on the most nearby stars (and their systems).
Hertz goes on to say, “Now that we know there are more planets than stars in our universe, I look forward to the strange, fantastic worlds we’re bound to discover.”
To find these strange and fantastic worlds, TESS will orbit the Earth for the next two years. NASA hopes that what TESS finds will add to efforts already (and continually) gathered by NASA’s Kepler space telescope, which was also built to look for habitable planets within our universe. Of course, TESS has the ability to spot planets much smaller than Kepler can see with NASA expecting/estimating the new craft will identify at least 20,000 exoplanets with between 500 and 1,000 of those with a rocky surface similar to that of our Earth.