By Emily Pennington

Many do not pay much attention to NASA until an astronaut lands on the moon or drives across the country wearing a diaper to kidnap the girlfriend of a former lover. Even in times of sparse media coverage NASA and its astronomers are always working diligently to further the exploration of space and all its veiled mysteries.

Bill Cochran, UT astronomer and co-investigator for NASA’s Kepler mission in search of planets similar to Earth, has been working under the radar to uncover the mysteries of space. Recently, more than ten years of Cochran’s hard work has proved fruitful. In January, at the 215th meeting of the American Astronomical Society in Washington, D.C.,  the Kepler mission astronomers announced the discovery of five new planets.

“It’s the most exciting thing that’s come along in planetary science, ever,” Erik Brugamyer, a UT graduate student of astronomy and Kepler team member, said.

The five planets are gas giants ranging in size from 40 percent to 1.7 times the size of Jupiter, and one is the least dense planet ever discovered. While unearthing these planets is not the team’s ultimate mission, it plays a crucial role in potentially finding life elsewhere in the universe, Cochran said.

“The end goal is to find planets like Earth,” Cochran said. “That has sort of two major aspects to it, it means something the size of Earth, a rocky type of terrestrial planet as opposed to a gas giant like Jupiter; it also means being at the distance from the parent star so you can have liquid water on the surface … so that potentially life could develop there.”

The Kepler mission officially began in 2000 when Cochran and Bill Borucki, a scientist at NASA Ames Research Center in California, submitted a proposal to NASA for a spacecraft that could consistently measure the brightness of more than 100,000 stars for three and one-half years to determine if planets are orbiting them. The proposal was accepted and the  Kepler spacecraft launched almost a decade later in March 2009.

Kepler, a hall monitor in space, is a NASA Discovery mission funded by NASA’s Science Mission Directorate at NASA headquarters in Washington, D.C. It operates by using a photometer, an instrument that measures light, to monitor the brightness of the stars while also looking for the periodic dimming of the stars’ brightness. According to the Kepler Web site, Kepler has a field of view comparable to the area of your hand held at arm’s length. A change in the brightness of a star, which implicates that an object has passed in front of it, is referred to as a transit.

Kepler’s photometer sends this information to the ground base team, which includes researchers Bill Cochran, Michael Endl, Phillip Macqueen and two UT at McDonald Observatory graduate students, who further determine the planets’ characteristics.

Cochran said this is the only project in the world capable of finding habitable Earth-like planets. “This mission is a very crucial step on the path to trying to find life in the Universe,” he said. “First you have to have a place for that life to exist.”

Of the approximate 350 planets that have been found orbiting stars other than the sun in the last decade, none have been found with masses as low as Earth’s. “Nobody knows how frequent planets like the Earth are … because they’re so difficult to find. The whole galaxy could be full of them and we’d never know it,” Endl said. “Kepler is our first shot at finding them.”

However, not all  Kepler’s Objects of Interest are planets . That is where UT’s team comes in. To ensure the team finds Earth-like planets should they exist, the researchers wade through the objects of interest that yield many false positives, such as two stars orbiting each other or positives due to random noise.

Cochran estimated they have 200 KOI’s from just 50 days worth of Kepler’s observation, not all of which are planets. “What we have to do is go through this vetting process of taking all of these possible transits and deciding which ones are real planets and which ones are not,” Cochran said.

Once it is known that a transit is made by a planet, the team determines its size, density and distance from the star it orbits using equipment such as the Hobby-Eberly Telescope and the Harlan J. Smith Telescope, which tells them how hot it is.

What makes the team’s research difficult, Macqueen said, is that the stars Kepler monitors are very faint. They are farther away than the stars the researchers normally observe. Kepler is able to look at stars with a magnitude of 13, 14 or 15, while the ground base team views them with a magnitude of six to nine.

Macqueen, the chief scientist at McDonald Observatory, who specializes in making the instruments and telescopes used by the team more effective and sensitive, said all of the planets discovered by Kepler are between ten and 100 light years away. “They’re basically in our solar neighborhood within the Milky Way,” he said. The Milky Way has 100 million stars within it.

The team is at a standstill until summer because Kepler is staring at a region of the sky in the constellation Cygnus. In the meantime, the team is working out what they will do in April when they start visiting the observatory again once a month through the end of summer.

“Kepler is a big deal and we want to maximize UT’s contribution,” Macqueen said.