At 114 times the mass of our own Sun, a star at the centre of nebula NGC 3603 is the fattest ball of fusion ever measured by astronomy types. In related star news, the recently-feted Gleise 581 has failed to show any transits to telescopes, which means that we haven’t learned any more about the potentially-habitable planet that orbits it – but we do know that Gleise itself is stable in output, which is a positive sign. If you need to cheer yourself up after that minor downer, why not browse through the fresh high-resolution images of Mars that have been collected by the HiRISE orbiter?