NASA ties up with universities to develop planet-searching satellite

Mumbai: The NASA Ames Research Center will develop the first of the planet-searching satellites along with scientists from MIT, the Harvard-Smithsonian Center for Astrophysics, as part of the six proposed spacecraft concepts that NASA has picked for its Small Explorer (SMEX) satellite programme.

The planet-searching satellite would have the potential to discover hundreds of "super-Earth" planets, ranging from one to two times Earth's diameter, orbiting other stars, an MIT release said.

The six projects, announced last week, were selected from among 32 proposals submitted to NASA in January. Each of the six will receive $750,000 for a detailed six-month feasibility study. In early 2009, two of the projects will get the go-ahead for development at a cost of no more than $105 million, excluding the launch vehicle, with the first launch as early as 2012.

The proposed satellite, called the Transiting Exoplanet Survey Satellite (TESS), would use a set of six wide-angle cameras with large, high-resolution electronic detectors (CCDs) being developed in cooperation with MIT's Lincoln Laboratory, to provide the first-ever spaceborne all-sky survey of transiting planets around the closest and brightest stars.

The satellite would search for stars whose orbits as seen from Earth carry them directly in front of the star, obscuring a tiny amount of starlight. Some ground-based searches have used this method and found about 50 giant planets so far, but a space-based search could detect much smaller Earth-sized planets, as well as those with larger orbits.

This transit-detection method can pinpoint the planet's size by measuring the exact amount of light obscured by the planet. Spectroscopic follow-up observations can then determine the planet's mass and thus its density, giving clues to its composition, as well as determine its temperature, probe the chemistry of its atmosphere, and perhaps even find signs of life such as oxygen in its air.