Stay up late tonight (or get up early in the very wee hours) to observe an asteroid block a star, then report what you see for SCIENCE! This only applies to eastern inhabitants of North America, but you're vital to figuring out the shape of this rock & if it has a mini-moon.
In the wee hours on Thursday morning, the asteroid 163 Erigone will briefly occult the star Regulus. If you live anywhere from the Carolinas to Nova Scotia to Winnipeg, and have skies dark enough to see the stars, stay up late and report your observations!
Occultation of Regulus in the constellation Leo. Image credit: Sky & Telescope
The asteroid will pass between us and the star for about 14 seconds. Anyone in the New York region should see it happen at 2:06 am EDT on Thursday March 2oth. Those further north will have the show delayed by a few minutes. If Erigone has an orbiting mini-moon, people further west or east might see it briefly block out Regulus any time from 2:00 to 2:12 am EDT (1:00 to 1:12 CDT).
Predicted occultation map. Image credit: International Occultation Timing Association
Regulus is fantastically bright, which means that not only should you be able to see it through urban light pollution, but it's also dead-easy to find. Go outside. Look at the moon. Then look to your right at the same height above the horizon. That bright star is Regulus.
By getting observations from people all over the region, we'll be able to map out the asteroid's shape and size, and if it has a miniature satellite-asteroid. Reports of, "The star didn't disappear at all, I was cheated!" are vitally important, as they'll help determine the asteroid's width. The International Occultation Timing Association has a detailed write-up, maps, videos, and even an app for the event.
Update: If you're in New York, astronomers will be out at bars to help people see the star-wink.