Artist's concept depicts Kepler-186f, the first validated Earth-size planet to orbit a distant star in the habitable zone. Image Credit: NASA Ames/SETI Institute/JPL-Caltech
The Kepler Mission built for NASA has revolutionized our understanding of exoplanets. Kepler’s mission was to search for Earth-size planets in the habitable zone -- the region in a planetary system where liquid water could exist on the surface of an orbiting planet – around sun-like stars in our galaxy.
During its five years on orbit, Kepler has discovered:
- Over 3,600 planetary candidates
- Over 700 multi-planet systems
- The first small planet in the habitable zone (Kepler-22b)
- Three Earth-sized planets in the habitable zones around their stars
- The smallest exoplanets ever detected (KOI-961.01, KOI-961.02, KOI-961.03)
- Five worlds (Kepler-16b, Kepler-34b, Kepler-35b, Kepler-47b, Kepler-47c) that orbit around two stars, establishing a new class of planetary system
Launched in March 2009, the Kepler photometer identifies planet candidates by continuously measuring the tiny change in brightness of more than 150,000 stars to detect when a planet transits the face of the star. The size of the planet can be derived from these periodic dips in brightness.
Ball Aerospace is the mission prime contractor, which includes responsibility for the photometer, spacecraft, system integration, testing and on-orbit operations for the Discovery Class mission.
Ball Aerospace employed its instrument expertise from successes such as Hubble Space Telescope in the photometer for Kepler and the spacecraft design used in Deep Impact for providing power, communications and telescope pointing.
K2 Mission: Kepler’s Second Light
After completing its nominal mission, Kepler operations were suspended due to a reaction wheel failure, but today an exciting new science mission, K2, has been funded. Ball engineers devised an innovative way to control pointing in the spacecraft by managing solar pressure and using thrusters. The K2 mission provides an opportunity to continue Kepler’s ground breaking discoveries in the field of exoplanets and expand its role into new astrophysical observations.
K2 will perform a series of 80-day campaigns that use the proven Kepler spacecraft team to conduct new research into planet formation, young stars, stellar structure, evolution and activity, and extragalactic science. K2 will observe tens of thousands of stars per campaign and will transmit science data to the ground once every 80 days. K2 will search for new planets around bright stars and habitable worlds around M class stars to help pave the way for future missions like the Transiting Exoplanet Satellite Survey and the James Webb Space Telescope.
UPDATE: NASA Headquarters has approved the K2 mission and funded it for 2 years. According to the NASA 2014 Astrophysics Senior Review Report:
“This is an outstanding mission and we look forward to the results from the program. K2 uniquely addresses a range of observational goals and is expected to engage a broad community of scientists.”
Image Credit: NASA Ames/W. Stenzel