Looking for Earths in All the Right Places
STScI Joins the Search for Other Earths in Space
The Institute was the logical choice for storing the anticipated flood of data because its scientists have processed enough observations from NASA’s Hubble Space Telescope over the past 19 years to fill almost two collections of material in the U.S. Library of Congress.
The Institute’s role is to convert the raw science data into files that can be analyzed by Kepler researchers and to store the files every three months in an archive.
“We are part of this mission because of our experience with Hubble data processing and archiving,” explained David Taylor, project manager for the development of Kepler’s Data Management Center at the Institute. “NASA’s Ames Research Center [the home of Kepler’s science operations] had not done a science mission like this one. Building the Data Management Center from scratch would have been more costly, and it would have taken longer to get up to speed.”
Launched on March 6 on a Delta II rocket from Cape Canaveral, Fla., the Kepler spacecraft will spend the next 3 1/2 years searching for habitable planets by staring nonstop at more than 100,000 Sun-like stars out of about 4.5 million catalogued stars in the spacecraft’s field-of-view, located in the summer constellations Cygnus and Lyra.
When the mission is completed in several years, the survey should tell astronomers how common Earth-size planets are around stars.
Once a month, the Kepler spacecraft will send its science data, about 50 gigabytes, back to Kepler’s Mission Operations Center at the Laboratory for Atmospheric and Space Physics at the University of Colorado. Raw science data will then be relayed to the Institute’s Data Management Center (DMC). DMC Operations will convert the information into Flexible Image Transport System (FITS) files, a digital file format used to store, transmit, and manipulate scientific information. FITS is the most commonly used digital file format in astronomy.
The FITS files will be sent to the Kepler Scientific Operations Center (SOC) at Ames Research Center in California, where the science data analysis will be carried out.
Kepler mission scientists will turn the data into 30-minute snapshots of light from each of the 100,000 or more stars. From these snapshots, the scientists will construct a light curve for each star, which details any brightness fluctuations. They will review the light curves to look for any periodic decrease in brightness, an indication of a possible transiting planet.
The mission scientists also will use the light curves to study the stars and their interiors. Because of the quality of the Kepler data and the large number of stars the spacecraft will observe, scientists hope to improve their understanding of stellar evolution.
A planet at an Earth-like distance from its star would be in the star’s “habitable zone,” where temperatures are just right for liquid oceans to exist on the surface without freezing over or evaporating away. On Earth, a liquid ocean was needed to nurture the chemical processes that lead to the appearance of life. This is considered an important prerequisite for life as we know it to appear elsewhere in the galaxy.
Kepler’s science data also will be archived at the Institute. Every three months the SOC at Ames will ship FITS files in a 500-gigabyte computer hard drive to the Institute for storage in the Multimission Archive, or MAST. The archive houses data from about 14 missions, including Hubble, the Far Ultraviolet Spectroscopic Explorer (FUSE), and the Galaxy Evolution Explorer (GALEX).
Based on its strong track record in processing and archiving data, the Institute could earn a role in many future missions.
“Partnering with other institutions to share the duties of a mission may be a trend for future missions,” Taylor said.