An Eclipse of Regulus, March 20, 2014

On March 20, 2014, a very rare event will occur. For a few people in a narrow band that includes New York City, Utica NY, Bridgeport CN, and Kingston ON, at around 2 in the morning, the bright star Regulus will disappear. Asteroid 163 Erigone will pass between observers and the star that night, and, just like a solar eclipse, anyone who happens to be in the shadow will see the star disappear.  Asteroids move pretty quick though, and their shadows are tiny, so don’t blink or you might miss it! Luckily, Regulus is a bright star, so it’s usually visible even in pretty bad skies.

There’s a lot we can learn from this event too, and scientists are looking for your help! We don’t actually know a whole lot about Erigone. Observations of how long it lasts and where people were actually able to observe the occultation help scientists characterize the asteroid and its motion. Think about the shadow of a badly thrown football compared to the shadow of a well thrown tennis ball. Simply knowing where the shadow fell and for how long will tell scientists something about the shape of the asteroid and (if it’s not round) if it’s tumbling.

If you aren’t in the narrow path of the shadow, but aren’t too far away, you can still help. If Erigone has a moon, the moon’s shadow may be several hundred miles from the main shadow. You could be part of a very small group of people to discover that moon!

Additionally, it may be possible to learn about Regulus. Anyone who can do imaging or photometry can help measure how the light curve, which can be used to put limits on the diameter of star.

For a map of the path, and to find out more about how to make and report an observation, visit
http://occultations.org/regulus2014/