NASA hails primary mission of planet-hunting TESS a "roaring success"
Launched in 2018 as the successor to the Kepler Space Telescope, NASA had high hopes for its Transiting Exoplanet Survey Satellite (TESS) when it comes to finding other worlds that resemble our own. The space telescope has now wrapped up the primary phase of its mission, completing an extensive survey of the starry sky that revealed 66 new exoplanets and thousands more candidates.
TESS uses a set of four low-power and low-noise digital cameras to study stars up to 30,000 light years away, and up to 100 times brighter than those studied by Kepler. It searches for planets around these stars through what is known as the transit method, monitoring those stars for dips in light that could be indicative of a body passing in front of them.
It was in April of 2019, around a year after it launched, that TESS identified its first Earth-sized exoplanet, a small planet called HD 21749c that circles its parent star around 52 light years away. Other alien worlds followed, some with big scientific potential, along with its first detection of an Earth-sized planet in the habitable zone earlier this year.
But TESS’ achievements aren’t just limited to the discovery of intriguing planets that could harbor the conditions necessary for life. The telescope has also captured comet outbursts and white dwarf supernovae, and even observed a black hole tearing apart a distant star.
The primary mission for TESS began in July of 2018 and wrapped up in early July of 2020, and saw the telescope image around 75 percent of the sky. In addition to the 66 exoplanets already discovered, it has found 2,100 candidates that astronomers are now investigating further.
Now moving into its extended mission, the TESS team has made a few improvements to the methods used to gather intel. The space telescope can now capture images three times faster than during its primary mission, snapping one every 10 minutes, and can measure the brightness of thousands of stars every 20 seconds.
The extended mission is expected to run until September 2022, starting with a year scanning the southern sky, followed by a 15-month survey of the northern sky and areas along the plane of Earth’s orbit around the Sun.
“TESS is producing a torrent of high-quality observations providing valuable data across a wide range of science topics,” says Patricia Boyd, the project scientist for TESS at NASA's Goddard Space Flight Center in Greenbelt, Maryland. “As it enters its extended mission, TESS is already a roaring success.”