Eyes open

STFC’s Space Science Department at the Rutherford Appleton Laboratory (RAL) has built instruments for three space missions, two already launched, to enable research into the Earth, Moon and Sun.

Mapping the Moon

In January 2009, an X-ray camera developed jointly by RAL and the Indian Space Research Organisation (ISRO) successfully detected its first X-ray signature from the Moon.

The instrument is onboard the Chandrayaan-1 spacecraft, India’s first mission to the Moon. C1XS (Chandrayaan-1 Imaging X-ray Spectrometer) detected the signal from a region near the Apollo landing sites. The lunar signal resulted from the reflection of a weak solar flare around twenty times smaller than C1XS was designed to detect.

This compact X-ray camera will continue to build up a detailed picture of the Moon, mapping the surface composition and mineral resources as well as helping scientists understand its origin and evolution.

Predicting solar storms

RAL instruments are also part of NASA’s STEREO mission. STEREO’s two identical spacecraft were launched in 2006, each carrying a UK-built Heliospheric Imager. The aim of the mission is to image the solar atmosphere between the Earth and the Sun in three dimensions as well as determine the speed and direction of solar storms.

Solar storms are coronal mass ejections, where the Sun spews out hot gases and magnetic energy across space at around a million miles an hour. They can pose a hazard for astronauts and affect communications and satellites – disrupting technologies ranging from GPS to power stations. A huge solar storm in 1989, for instance, shut down Quebec’s entire power grid.

In December 2008 STEREO observed a weak solar storm heading towards Earth. It caused the Earth’s magnetic field to wobble and this characteristic signature was picked up by instruments on the ground within an hour of the storm arriving. “The images taken from the UK-built Heliospheric Imagers represent a major step forward in predicting the arrival of these storms at Earth,” said RAL’s Dr Chris Davis.

Protecting our planet UK scientists are also working on a European-Japanese mission called EarthCARE (Earth Clouds, Aerosols and Radiation Explorer). Due for launch in 2013, EarthCARE aims to improve our understanding of the Earth’s radiation balance and the role it plays in regulating our climate. This will help improve climate prediction models and weather forecasts.

The mission will profile clouds, aerosols and any outgoing radiation from the top of the atmosphere. RAL is supplying the Optics Unit to the UK company SEA, who won the ESA (European Space Agency) contract for the Broad Band Radiometer (BBR). RAL will also assemble, test and calibrate the instrument. BBR will take images, simultaneously, of both the Earth’s reflected sunlight and its emitted heat.