If you are on or near the centerline of the path of totality during the solar eclipse on August 21, 2017, you are able to participate in an activity to observe and record the faintest stars visible as a means of measuring how dark the daytime sky gets. By locating and observing the constellation Ursa Major (e.g, the Big Dipper) midway during the solar eclipse and comparing it to stellar charts, your “measurement” and submission of that measurement to the online database will document darkness levels of a daytime sky during a total solar eclipse. Your measurement will help scientific research.

For information on how to take your measurement, see the Globe at Night website. Globe at Night is a program of the National Optical Astronomy Observatory, operated by the Association of Universities for Research in Astronomy (AURA) under cooperative agreement with the National Science Foundation.