(Reuters) – The search for worlds circling stars far beyond our solar system wants to be intensified in the coming weeks with NASA's launch of a spacecraft
NASA plans to send the Transiting Exoplanet Survey Satellite, or TESS, into the Kennedy Space Center in Florida aboard a SpaceX Falcon 9 rocket set for blast-off on April 16 on a two-year, $ 337-million mission.
The latest NASA astrophysics endeavor is to build on the work of its predecessor, the Kepler space telescope, which discovered the bulk of some 3,500 exoplanets during the past 20 years, revolutionizing one of the newest fields in space science.
NASA expects TESS to detect thousands more previously unknown worlds, perhaps hundreds of them Earth-sized or "super-Earth" -sized – no larger than twice as big as our home planet.
Jupiter or Neptune.
Jupiter or Neptune.
Astronomers said they would like more about 100 more rocky exoplanets for further study.
The new sample will take about 60 days to reach its highly elliptical, first-of-a-kind orbit that will loop TESS between Earth and the moon every two and a half weeks.
Kepler's positioning system broke down in 2013 about four years after its launch, and scientists have found it almost run out of fuel.
"So it's perfect timing that we'll be launching." Paul Hertz, NASA's director of astrophysics, told reporters at a news briefing in Washington on Wednesday.
TESS, roughly the size of a refrigerator with wings, is equipped with 200,000 stars that are near the sun and thus among the brightest in the sky, seeking out those with planets of their own ,
Like Kepler, TESS wants to use a detection method called transit photometry, which looks for periodic, repetitive dips in the visible light from stars passing through, or transiting, in front of them.
But unlike Kepler, TESS wants to scan the majority of the heavens for shorter periods of time and focus on the topic of red dwarfs, which are smaller, cooler and longer-lived than our sun.
David Latham, TESS science director of the Harvard-Smithsonian Center for Astrophysics, said: "One reason is red dwarfs have a high propensity for Earth-sized, presumably rocky planets.
So because red dwarfs are so small, and their planets orbit more than the Earth does, the dip in a planetary transit of a red dwarf is more pronounced compared to a larger star, Latham said.
"It's easier to find interesting planets around smaller stars," he said.
Measuring the dips in starlight can determine the exoplanet's size and orbital path.
Martin Still, the TESS program scientist for NASA, said more than 50 rocky, Earth- or super-Earth-sized planets have previously been identified, and NASA expects to increase that number through the new mission.
The most favorable explorations will undergo closer scrutiny by a new generation of larger, more powerful telescopes now under development that will search for telltale signs of water and "the kinds of gases in their atmospheres that are on earth "Hertz said.
"TESS itself is not ready to be found beyond Earth, but TESS wants to help us figure out where to point our larger telescopes," he said.
Reporting and writing by Steve Gorman in Los Angeles; Editing by Sandra Painter and Chizu Nomiyama