Kepler Spacecraft Operation May Halt, But the Mission is Not Over

 Wednesday, May 15, 2013 - 3:45 pm, PDT

NASA announced today through a press conference that Kepler, its planet-hunting spacecraft, is currently malfunctioning and observations have been halted. Due to failure of one of the reaction wheels, the space telescope is now unable to point accurately toward the region of the sky that it has been observing continuously for 4 years to search for Earth-size planets around other stars.

NASA engineers placed the telescope in a stable and safe rest mode after the anomaly on reaction wheel #4 was detected on May 14. The spacecraft will soon be placed in a mode minimizing the fuel usage and allowing continuous communication with Earth. It is too early to call the mission over, even though it is unlikely that the spacecraft will recover sufficiently to allow high photometric mode observations needed to detect Earth-sized planets.

Launched on March 6, 2009, Kepler was funded to collect data for three-and-a-half years. It was designed to work for as long as 8 years. Kepler has already confirmed 132 exoplanets including several Earth-sized exoplanets. Over 2,700 additional exoplanet candidates have been identified, including ~350 roughly Earth-size planets. Three of the small candidates (less than twice the radius of Earth) were confirmed as planets in the habitable zone of their stars just one month ago.

The Kepler science office is currently analyzing the first 3 years of data and expects to publish the analysis of these data later this year. “Our understanding of the instrument and the stars has been improving significantly over the years. We are constantly tuning the data analysis, improving our sensitivity to detect the weak signatures  of transiting Earth-size planets”, says Jon Jenkins, Senior Researcher at the Carl Sagan Center of the SETI Institute and Kepler Mission Co-I.

Fourth year data will be analyzed later this year and Jason Rowe, Researcher at the Carl Sagan Center of the SETI Institute since 2008, is confident that more discoveries will be announced in the future with Kepler data.  “Even if the spacecraft operation has to stop, we will have to use our intelligence to find these Earth-analogs buried in the 4 years of data collected by Kepler. It has been a tremendous success, and changed our perceptions of our galaxy. Today we know that most of the stars indeed have planets,” says Rowe.

The future of exoplanetary science is bright, with the design of future instruments from the ground and in space capable of detecting and also characterizing exoplanets. Jenkins is co-Investigator of the TESS mission, a space telescope recently selected by NASA to search for transiting Earth-size planets around nearby bright stars. TESS will launch in 2017 to continue the search for exoplanets.

“The SETI Institute is proud to play a significant role in this scientific and human adventure. The search for exoplanets is without doubt one of the most game changing results in astronomy. The high frequency of planets revealed by the Kepler spacecraft helps us answer the fundamental question, ‘Are We Alone?’ ”, says Edna DeVore, CEO and Director of Education and Outreach at the SETI Institute. DeVore co-leads the education and outreach program for the Kepler Mission.

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About SETI Institute

The mission of the SETI Institute is to explore, understand and explain the origin, nature and prevalence of life in the universe. The SETI Institute is a private, nonprofit organization dedicated to scientific research, education and public outreach. Founded in November 1984, the SETI Institute began operations on February 1, 1985. Today it employs over 120 scientists, educators and support staff. Research at the Institute is anchored by three centers. Dr. Gerry Harp is Director of the Center for SETI Research (Dr. Jill Tarter continues as Bernard M. Oliver Chair for SETI). Dr. David Morrison is the Director for the Carl Sagan Center for the Study of Life in the Universe. Edna DeVore leads our Center for Education and Public Outreach.
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