Despite the mind-boggling temperature of the new planet, it may not necessarily keep hold of its record for long. Wasp-12b only just edges out the recently discovered HD 149026b, which is a searing 2040C. The discovery was made using two sets of telescopes, one in Spain's Canary Islands and the other in South Africa. They have been set up to search for signs of 'transiting' planets, which pass in front of and dim their host stars as seen from Earth.
Astronomers have found extrasolar planets too dim compared to their host stars to be directly measured, but the size of planets and orbital distances can be worked out from the transit observations. From this they can work out how much starlight falls on the planets and take their temperature.
Leslie Hebb, of the University of St Andrews, was part of the team which made the discovery.She explained the importance of the find, as most observed exoplanets have orbital periods of three days or longer. 'When the planets form and migrate inward, something is causing them to stop and preferentially stop with a period of three days,' she said. 'I was surprised that the period could be so much shorter.'
