Comet Ison 'vaporised' in Sun pass
28 November 2013 Last updated at 21:19 GMT
Comet Ison seems to have been destroyed in its encounter with the Sun.
Astronomers saw the giant ball of ice and dust disappear behind the star, but then fail to emerge as expected.
Francisco Diego from University College London said he saw the comet "fading" as it approached the Sun.