NASA’s TESS Starts Collecting Planets
Xeber24.net _ The New York Times
The satellite, launched in April, has already identified at least 73 stars that may harbor exoplanets, most of them new to astronomers.
Somewhere among these grains of celestial sugar and powder puffs of cloudy light there is a planet, perhaps many planets, perhaps even Earth 2.0, as astronomers sometimes call the object of their dreams — a terrestrial look-alike to our own world, a “Goldilocks” place not too hot nor too cold, Perhaps even life.
On Monday, astronomers who operate NASA’s new planet-hunting satellite TESS released what they call the satellite’s “first light science image.” Taken last August, it covers a swath of the Southern Sky showing stars and constellations and the Large and Small Magellanic Clouds, which are nearby galaxies in their own right, hanging like extragalactic fruit in nearby space.
Within this first patch of sky to be surveyed TESS, short for Transiting Exoplanet Survey Satellite, has already identified at least 73 stars that might harbor exoplanets, most of them new to astronomers, according to George Ricker, an astrophysicist at the Massachusetts Institute of Technology who leads the project. They all need to be confirmed by other astronomers, Dr. Ricker added.
“TESS is doing great — all that we could have wished for!” he wrote in a email.
In an explosion of research over the last three decades, spearheaded by NASA’s Kepler planet-hunting spacecraft, astronomers have concluded that there are billions of planets, including potentially habitable rocky worlds like Earth, in the Milky Way galaxy. The frequent occurrence of such planets means the closest one could be only 10 or 15 light years from here.
It will be TESS’s job to sniff out those planets, by monitoring the light from stars for periodic dimming or blinking that would indicate that planets are passing in front of them. Its designated prey are those planets close enough for the next generation of giant telescopes in space and on the ground to inspect for more promising signs of habitability or even life. There could be as many of 500 of them within 300 light years, TESS scientists say.
TESS was launched on April 18 from Cape Canaveral aboard a SpaceX Falcon 9 rocket, and is now ensconced in a looping orbit of the Earth that takes it all the way out to the moon and then back close to Earth to dump its data. It has four cameras that stare at orange slices of the sky from pole to equator for 27 days at a time.
Among the 73 candidates, the TESS team announced on Wednesday, is a so-called “super-Earth.” It circles the sun-like star Pi Mensae at a distance of about 7 million miles every 6.3 days, a distance Dr. Ricker described as “quite a bit too toasty” to be habitable by the likes of us. The same star was already known to harbor a planet some 10 times as massive as Jupiter with a six-year orbit. That leaves that star with two planets — one too hot and one too cold.
Only a day later they unveiled another possible planet, a so-called “hot earth,” that circles a nearby small dim red dwarf star known as HS 3844 in an incredibly tight orbit only about a million miles from its sun.
“The discovery of a terrestrial planet around a nearby M dwarf during the first TESS observing sector suggests that the prospects for future discoveries are bright. It is worth remembering that 90 percent of the sky has not yet been surveyed by either TESS or Kepler,” the TESS authors wrote.
In other words, Goldilocks is still waiting.