[Editors] NASA selects MIT-led team to develop planet-searching satellite

[Elizabeth Thomson]

For Immediate Release
TUESDAY, JUNE 3, 2008
Contact: Elizabeth A. Thomson, MIT News Office -- Phone: 617-258-5402  
-- Email: thomson at mit.edu

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NASA selects MIT-led team to develop planet-searching satellite
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CAMBRIDGE, Mass. - A planet-searching satellite planned by scientists  
from MIT, the Harvard-Smithsonian Center for Astrophysics and NASA- 
Ames is one of six proposed spacecraft concepts that NASA has picked  
for further study as part of its Small Explorer (SMEX) satellite  
program. 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.

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 followup 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.

Plans for TESS are being led by senior research scientist George R.  
Ricker, at the MIT Kavli Institute for Astrophysics and Space  
Research, as Principal Investigator, along with research scientist  
Roland Vanderspek and Jacqueline Hewitt, MIT professor of physics and  
director of the MIT Kavli Institute, and professors Sara Seager, Adam  
Burgasser, Jim Elliot and Josh Winn and others at MIT. TESS is part  
of a joint effort between the Department of Physics and the  
Department of Earth, Atmospheric and Planetary Sciences at MIT to  
study exoplanets. The project also involves scientists at the Harvard- 
Smithsonian Center for Astrophysics, including astronomer David  
Latham as Chief Mission Scientist, and Kimberley A. Ennico of NASA  
Ames Research Center as the Project Scientist.

The NASA Ames Research Center is a full partner in the TESS program.  
Their Small Spacecraft Division, formed in 2006, specializes in low- 
cost, rapid development of spacecraft and missions. Additional TESS  
partners include the NASA Goddard Space Flight Center, the Harvard  
Origins of Life Initiative, Lowell Observatory, Caltech's IPAC, the  
SETI Institute, Geneva Observatory in Switzerland, Tokyo Institute of  
Technology, SUPAERO in France, ATK Space, Espace Inc, and the  
privately-funded Las Cumbres Observatory Global Telescope Network.

The satellite's high-resolution, wide-field digital cameras are  
already under development, thanks to a seed grant from Google. The  
project has also received funding from the Kavli Foundation, the  
Smithsonian Institution, MIT alumnus Rick Tavan, and other donors.  
When the satellite is launched, the cameras will cover the whole sky  
in two years, getting precise brightness measurements of about two  
million stars in total. The planets discovered by the satellite would  
provide prime candidates for followup observations by NASA's new  
James Webb Space Telescope, which is set for launch in 2013.

Statistically, since the orientation of orbits is random, about one  
star out of a thousand will have a planet whose orbit is oriented so  
that the planet regularly crosses in front of the star, resulting in  
a “planetary transit”. So, out of the two million stars observed, the  
new observatory should be able to find more than a thousand planetary  
systems within two years.

“Because the TESS survey will systematically examine the entire sky  
for stars harboring exoplanets, the resulting TESS Transit Catalog  
will constitute a unique scientific legacy. Decades or even centuries  
after the survey is completed, it is likely that TESS-discovered  
super-earths will continue to be studied because of their proximity  
to Earth, and because their stars are so bright,” Ricker said.

--END--

Written by David Chandler, MIT News Office