Kepler Mission Manager Update
Since the last mission update the Kepler team has completed two science data downloads. The most recent data download on Oct. 5, 2012 included a quarterly roll to the fall science attitude. This marked the successful completion of Quarter 14 flight operations and the beginning of Quarter 15.
The spacecraft's performance continues to be excellent while operating on three reaction wheels. Analysis of the telemetry has revealed no new cause for concern regarding the remaining wheels, and engineers continue to take steps to assure their continued performance.
The Kepler spacecraft trails Earth in a drift-away heliocentric orbit and is currently 42 million miles away. Unlike NASA's Hubble space telescope, the spacecraft is not accessible for a servicing mission.
Meanwhile, scientists from around the world gathered Oct. 4-5, 2012 for the Kepler science working group (SWG) meeting in Mountain View, Calif. SWG members meet biannually to discuss the latest findings in the Kepler data and to discuss future plans.
Last week astronomers met in Reno, Nev. for the annual meeting of the American Astronomical Society's Division of Planetary Sciences (DPS). Fifty oral and poster presentations, including two plenary talks, featured exoplanet science results, many of which derived from Kepler data.
An exciting result presented at DPS was the first reported case of a planet orbiting a double-star that, in turn, is orbited by a second distant pair of stars. The phenomenon is called a circumbinary planet in a four-star system. Coined PH1, and also known as Kepler-64b, the planet was identified by the citizen scientists participating in Planets Hunters
, a Yale-led program that enlists the public to review astronomical data from the Kepler mission for signs of planets transiting distant stars. The result has been submitted to the Astrophysical Journal and is available on the preprint server- A Transiting Circumbinary Planet in a Quadruple Star System
(Schwamb et al, 2012).
Last week European astronomers announced another exciting result: the discovery of a planet with approximately the same mass as Earth orbiting a star in the Alpha Centauri system- the nearest to Earth. The research team presented novel techniques for separating out planet versus star signals in the Doppler data. It gives us hope that astronomers might one day get mass determinations using the Doppler method for many of Kepler's most interesting planets. The Kepler team applauds and celebrates this exciting milestone in the search to confirm companion worlds. The finding was published in the journal Nature- An Earth mass planet orbiting Alpha Centauri B
(Dumusque et al, 2012).
Earlier in October, the Science Operations Center (SOC) deployed version 8.3 of the pipeline software. The new version will allow the team to complete a multi-quarter processing run for the first 12 quarters of data. As noted in the previous update, SOC 8.3 will improve sensitivity for detecting small planets, and help improve the rejection of false positives.
On Oct. 28, 2012, the Kepler project will release 12 additional months of time series data collected between June 2011 and June 2012 to the public archive at the Barbara A. Mikulski Archive for Space Telescopes
, or MAST, at the Space Telescope Science Institute in Baltimore, Md. This data release marks a milestone for Kepler. As of October 28, all previously collected and processed data for the exoplanet survey will be in the public domain and all future data will be published to the public archive without delay.
During the baseline mission, Kepler data were retained by the mission for exclusive use to ensure they were properly calibrated and searched for transit signatures. A data release schedule was developed to balance the mission goals to identify transiting planets with public access to the data. Although Kepler has met or exceeded every data release milestone, this open data policy for the extended Kepler mission enables the entire scientific community to participate in the survey by finding new planetary candidates within increasingly longer baselines of data with the greatest possible efficiency. The new open data policy also allows greater accuracy in the public characterization of planetary and stellar properties within the Kepler survey.
Finally, Nov. 12, 2012 will mark the successful completion of Kepler's three and a half year prime mission. The team looks forward to continuing the search in the extended mission, as Kepler's best and most exciting discoveries are yet to come.