Comet ISON Set to Survive Its Pass By the Sun

Comet ISON on the morning of Oct. 8, seen with the 0.8-meter Schulman Telescope at the University of Arizona SkyCenter atop Mount Lemmon. Credit: Adam Block / CaelumObservatory.com While most Americans are looking forward to November 28 this year to (over)indulge in turkey and gratitude, astronomers have another reason to count down the days. That’s when Comet ISON, the Great Comet of 2013, will reach its closest approach to the sun (1.7 solar radii from the solar surface, or about 700,000 miles). Only then will they know for sure whether the comet will survive its close encounter and go on to provide spectacular views for skywatchers on Earth.