Spinning Truths

A spacecraft that could service Earth observation satellites in orbit, ensuring their data is accurate, is being proposed by UK researchers.

Information produced by these satellites is used to determine the causes of global warming and assess the threat from climate change. They measure solar radiation hitting and being reflected off the Earth to produce a diagnosis of the planet’s health.

But researchers cannot be sure that the instruments used to gather this data are accurate enough once the satellites have gone through a violent launch and been in space for some time.

This uncertainty allows climate change sceptics to dispute the data produced, said Dr Nigel Fox, head of science in the optical radiation measurement group at the National Physical Laboratory. Accurate data would provide unequivocal evidence to support national and international legislation, he said.

As the satellites cannot be brought back to Earth, Fox is proposing to build a calibration laboratory that can be launched into orbit, against which all other satellites can be tested. As it is in orbit, the device, called Truths (Traceable Radiometry Underpinning Terrestrial and Helio Studies) would view the sun and Earth through the same atmospheric conditions as the instruments on the satellites.