Astronomy Picture of the Day . ... Second planet from the Sun and third brightest celestial object after the Sun and Moon, Venus has been appreciated by casual sky gazers as a brilliant beacon above the horizon after sunset. ... Brain Crater on Mars . ... Comet NEAT (Q4) Over Indian Cove . ... Although the head and part of the tails of Comet C/2001 Q4 (NEAT) were visible to the unaided eye, the best views of the colorful tail were revealed only later by cameras able to expose for long periods. ...