Look to the stars this week for a chance to spot Comet Tsuchinshan–ATLAS — a “ cosmic snowball ” that is visible to Earthlings only every 80,000 years.
The ideal time to catch a glimpse of the comet is between 6:45 and 7:15 p.m. on Friday, Oct. 11 and Saturday, Oct. 12, according to former Madison Astronomical Society (MAS) president and astrophotographer John Rummel . And it’s critical, he adds, to find a location that has a “very flat western horizon.”
“Ideally, get yourself to a hill that has a really good view to the west,” says Rummel. “Blue Mound [State Park, near Mount Horeb] has two fire towers which will put you above the local trees and hills and give you a spectacular view.”
On Sunday, Oct. 13, Comet Tsuchinshan–ATLAS will be about 21 degrees above the sun. Rummel shared an easy way for novice stargazers to locate the comet.
“To measure angles on the sky, hold your fist out at arm’s length. The width of your fist is approximately 10 degrees,” he says. “You can use the width of your fist to estimate where you should be able to spot the comet as the sky begins to darken after sunset.”