Using the Hubble Space Telescope, astronomers have, for the first time, observed the atmosphere of an extrasolar planet evaporating into space. Much of this planet may eventually disappear, leaving only a dense core. It is a type of extrasolar planet known as a ‘hot Jupiter’. These giant gaseous planets orbit their stars very closely, drawn to them like moths to a flame. The scorched planet called HD 209458b orbits ‘only’ 7 million kilometres from its yellow Sun-like star. By comparison, Jupiter, the closest gas giant in our Solar System, orbits 780 million kilometres from our Sun. NASA/ESA Hubble Space telescope observations reveal a hot and puffed-up evaporating hydrogen atmosphere surrounding the planet. This huge envelope of hydrogen resembles a comet with a tail trailing behind the planet. Earth also has an extended atmosphere of escaping hydrogen gas, but the loss rate is much lower.