If so, Comet ISON would rank as the most brilliant comet since the Great January Comet of 1910 became easily visible in daytime skies. (discovermagazine.com)
Three, possibly four, super-Earths have been detected in the habitable zone around Star C (more), view of daytime sky from planet «d» as imagined by Kormmesser. (members.nova.org)
Crab Nebula (1054): The supernova responsible for the famous Crab Nebula lit up even daytime skies, possibly rivaling the full moon in brightness. (discovermagazine.com)