Astronomers will use NASA's Kepler Mission to search for stellar oscillations

Astronomers from the South African Astronomical Observatory and the University of Cape Town will be working on the data from this ambitious and exciting space mission.
On 7 March 2009 at 03:50 Universal Time [05:50 am local South African Time] NASA plans to launch the Kepler Spacecraft into orbit around the Sun. The launch will be from launch pad 17B at Kennedy Space Center in Florida. The goal of this mission is ambitious and exciting. Using Kepler, NASA expects to answer a very fundamental question: do planets the size of Earth exist in orbit around other stars? The Kepler Spacecraft is equipped with a large telescope that will measure the variations in brightness of 170,000 stars simultaneously and continuously for a period of at least 3.5 years.
NASA’s Kepler mission will not only be able to search for planets around other stars, but also yield new insights into the parent stars themselves. Kepler’s measurements of changes in stellar brightness can also be used to study stars and their interiors.
Kepler mission scientists are expected to answer a host of questions about stars in our galaxy: How old are stars? How do they evolve? Is the Sun a typical star?  How does matter behave under the extreme conditions in stars?
Stars like our sun can “ring like a bell” due to sound waves which will result in oscillations of the whole star.  Kepler’s precise photometry will be able to measure these oscillations by recording small variations in a star’s light and conduct “stellar seismology,” in a similar way geologists probe Earth’s interior through earthquakes which make waves move in the Earth's interior. If the surface of the star is oscillating, Kepler will detect periodic variations over time spans from weeks to months and years and the Kepler team will be able to measure the precise periods of those stellar oscillations. The Kepler team will use seismic techniques to probe the cores of a large number of stars. This will allow the team to determine the size of stars, and to measure a star’s chemical composition as well as rotation rate.
For many of the stars where accompanying planets will be detected, the astronomers expect to use stellar seismology to determine the parent star’s age.  Do stars that host planets have the same age as the Sun and the Earth?
The quality of the Kepler data and the large number of stars observed are expected to lead to a huge step forward in understanding of stellar evolution. During the first nine months in space Kepler will survey more than 5000 stars for oscillations. Based on those measurements around 1100 stars will be followed for detailed studies throughout the full mission. The accuracy with which Kepler will be able to measure stellar oscillations is so high that the science team expects to watch directly the change in stars as they age.
In order to allow scientists worldwide to participate in analyzing the huge dataset, a scientific consortium has been formed, aiming at maximizing the scientific use of the data. This consortium, Kepler Asteroseismic Science Consortium (KASC), includes more than 200 researchers from 50 institutions all over the world.
Astronomers, Dr Luis Balona from the South African Astronomical Observatory and Dr Thebe Medupe from the University of Cape Town, will as active members of the Kepler Asteroseismic Science Consortium take part in the analysis of this exciting data set. The expertise from South African astronomers will be used to extract the detailed seismic information for the stars observed by Kepler. Dr Luis Balona and Dr Thebe Medupe are busy preparing for the analysis of the data and selected some of the stars that will be observed by the Kepler Spacecraft.
For more information refer to the NASA press release.
Local contacts: Dr Luis Balona, South African Astronomical Observatory, Observatory, Telephone: +27 (0)21 460 6292; email: lab(at)saao.ac.zaDr Thebe Medupe, University of Cape Town, Rondebosch, South Africa, Telephone: +27 (0)21 650 2393; email: thebe(at)baghayogo.ast.uct.ac.za Kepler is a NASA Discovery mission. NASA's Ames Research Center is the home organization of the Science Principal Investigator and is responsible for the ground system development, mission operations and science data analysis. Kepler mission development is managed by JPL. Ball Aerospace & Technologies Corp., Boulder, Colo., is responsible for developing the Kepler flight system and supporting mission operations. More information about the Kepler mission is at www.nasa.gov/kepler