For a comet, visiting the sun is risky business. Fierce solar heat vaporizes gases long frozen in the fragile nucleus, breaking up some comets and completely destroying others.
That’s why astronomers weren’t sure what would happen in early March when Comet Pan-STARRS, a first-time visitor to the inner solar system, dipped inside the orbit of Mercury. On 10th March , NASA’s STEREO-B spacecraft watched as the comet made its closest approach to the sun only 28 million miles away. At that distance, the sun loomed 3 times wider and felt more than 10 times hotter than it does on Earth.
The comet survived.
Still intact, Comet Pan-STARRS is emerging from the Sun’s glare into the sunset skies of the northern hemisphere. Solar heating has caused the comet to glow brighter than a first magnitude star. Bright twilight sharply reduces visibility, but it is still an easy target for binoculars and small telescopes 1 and 2 hours after sunset. As of March 15th, people are beginning to report that they can see the comet with the unaided eye. Click image to see You Tube video.