CCDs for Kepler

Chelmsford-based aerospace component manufacturer e2v has supplied the charged-coupled device (CCD) imaging sensors to be used by Kepler, NASA’s mission to find Earth-like planets.

The Kepler spacecraft was launched on its three-and-a-half-year mission from Cape Canaveral on 6 March with 42 of e2v’s CCD90 high-performance CCDs on board.

Kepler was designed by NASA and Ball Aerospace & Technology to monitor more than 100,000 sun-like stars in our galaxy, looking for tiny reductions in their light output that could signal the passage of a planet in front of them.

The frequency of the orbit - the year length of the planet - will determine whether the planet is in the habitable zone, or the distance from the star where there could be liquid water, considered essential to life.

According to NASA, for a planet in an Earth-size orbit, the chance of it being aligned to produce a visible transit is less than one per cent. For an Earth-size planet transiting a solar-like star, the change in brightness is only 84 parts per million.

Ball Aerospace designed, built and tested Kepler’s photometer, a specially designed 0.95m-aperture, wide field-of-view Schmidt telescope with a 1.4m primary mirror. The array of CCDs takes intentionally defocused images to improve the photometric precision. 

John Troeltzsch, Ball Aerospace programme manager, said: ‘e2v's imaging sensors are the heart of the Kepler mission. The CCDs will allow Kepler to detect Earth-like planets orbiting in the habitable zone around other stars and possibly answer the million-dollar question, are we alone?’

Brian McAllister, general manager of space and scientific imaging at e2v, said: ‘e2v is proud to be able to help NASA accelerate discovery by supplying imaging sensors for this telescope. This will be the largest camera launched in space and promises some exciting discoveries.’