(Reuters) – The search for worlds that go far beyond our solar system will continue in the coming weeks with NASA launching a spacecraft. Scientists hope to expand the well-known catalog of so-called exoplanets that can support life.
NASA plans to launch the Transit Exoplanet Survey Satellite (TESS) from Kennedy Space Center in Florida on a SpaceX Falcon 9 rocket between April 16 and June two-year mission worth $ 337 million.
The latest NASA astrophysics project builds on the work of its predecessor, the Kepler Space Telescope, which discovered the bulk of some 3,500 exoplanets in the last 20 years, revolutionizing one of the newest areas of space exploration.
NASA expects TESS to discover thousands of other previously unknown worlds, perhaps hundreds of them the size of Earth or the "Super Earth" – no larger than twice as large as our home planet.
It is believed that such worlds have the greatest chance of having rocky surfaces or oceans, and are therefore considered to be the most promising candidates for the evolution of life, as opposed to gas giants similar to Jupiter or Neptune.
Astronomers hope that somewhere between 10 and 30 more rocky exoplanets will be available for further investigation.
The new probe will take about 60 days to reach its highly elliptical, unique orbit, which TESS will ground every two and a half weeks between Earth and Moon.
Kepler's positioning system broke down in 2013, about four years after its launch, and has almost no fuel left.
"So it's the perfect timing that we'll be launching TESS to continue the great activity of searching for planets around stars other than our Sun and thinking about what it might mean for life in the universe," Paul said Hertz, director of NASA astrophysicists, told reporters at a news conference in Washington on Wednesday.
TESS, which is about the size of a refrigerator with solar panels, is equipped with four special cameras to observe 200,000 stars that are relatively close to the sun and thus among the brightest in the sky to look for those with their own planets.
Like Kepler, TESS will use a detection method called transit photometry, which looks for periodic, repetitive, visible-light collapses of stars caused by planets passing or passing them.
But unlike Kepler, who saw stars within a tiny fraction of the sky, TESS will scan most of the sky for shorter periods of time and focus much of his attention on stars known as smaller, colder and smaller dwarfs as our sun.
One reason is that Red Dwarfs have a high propensity for Earth-like, probably rocky, planets, making them a potentially fertile ground for closer investigation, said David Latham, TESS Science Director of the Harvard-Smithsonian Center for Astrophysics.
Also, because red dwarfs are so small and are orbiting their planets closer than the earth does to the sun, the incidence of light from a red dwarf planetary transition is more pronounced compared to a larger star, Latham said.
"It's easier to find interesting planets around smaller stars," he said.
By measuring dips in starlight, the size and orbit of the exoplanet can be determined. Further observations of ground telescopes can provide their mass and ultimately the density and composition of the planet – whether largely solid, liquid or gaseous.
According to Latham, fewer than 10 rocky, earth or supernatural planets have been confirmed so far, and NASA hopes to double or triple that number through the TESS mission.
The most favorable discoveries are being scrutinized for a new generation of larger, more powerful telescopes, now looking for telltale signs of water and saying "the kinds of gases in their atmospheres that are a sign of life on Earth," said Hertz.
"TESS itself will not be able to find life beyond Earth, but TESS will help us figure out where to go for our larger telescopes," he said.
Reporting and writing by Steve Gorman in Los Angeles; Arrangement by Sandra Maler