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Globe at Night is an international citizen-science campaign to raise public awareness of the impact of light pollution by inviting citizen-scientists to measure & submit their night sky brightness observations. It's easy to get involved - all you need is computer or smart phone & follow these 5 Simple Steps!

Image courtesy Babak Tafreshi

Join us for the December, 2018 campaign!

So far in 2018 citizen scientists from around the world have contributed 7,311 data points! Help us achieve our goal of 15,000 data points this year!

Check out the Campaign dates & Constellations for 2018!

Can You Find Perseus?

Perseus the slayer of Cetus is most easily seen rising in the East in the winter. The constellation is most easily identifiable as what almost appears to be a wishbone of brightest stars, with the brightest being the center and chest of Perseus. The legs of Perseus are pointing southward and are the forked part of the wishbone and the body and head are the straight line leading up northward. It is easy to find Perseus by either looking southward from Cassiopeia or just to the left of Taurus the Bull.

Practice finding all the Globe at Night Constellations or review the Magnitude Charts.

The December 2018 campaign is using the Constellation Perseus. Check out the dates and constellations for our other campaigns during all 12 months of 2018.

Globe at Night is a program of the National Optical Astronomy Observatory, the national center for ground-based nighttime astronomy in the United States, operated by the Association of Universities for Research in Astronomy (AURA), under cooperative agreement with the National Science Foundation.