Hot, dense planet with eight-hour year

artist's impression of the new planet - An international team involving researchers at UCL has discovered a new planet, GJ 367 b, whose surface temperature may reach 1,500 degrees Centigrade - hot enough to melt all rock and metal - and which takes only eight hours to orbit its star. In a new study, published in the Science journal, the researchers show that the planet, which is 31 light years from Earth, is one of the lightest among the nearly 5,000 exoplanets (planets outside our own solar system) that are known today, with half the mass of Earth. It has a diameter of just over 9,000 kilometres - slightly larger than Mars. The team say the research represents a step forward in the search for a "second Earth" as it shows astronomers can determine the properties of even very small planets. Co-author Dr Vincent Van Eylen (UCL Mullard Space Science Laboratory) said: "In this new study, the size and mass of the planet were calculated using two methods, both of which involved analysing the light of the planet's star. One was to measure the minute dip in emitted light from the star as the planet passed in front of it. This was done using data from NASA's Transiting Exoplanet Survey Satellite (TESS).