Through the night, the figure of the great hunter Orion strides through southern skies. With two of the brightest stars at opposite corners of his hourglass shape bisected by three parallel stars marking his belt, Orion is one of the most familiar constellations in the heavens.
Now, with just a few minutes spent gazing at Orion and reporting your sightings, you can join the cadre of international amateur astronomers contributing to make a world-wide night-sky map. In its sixth year, the GLOBE at Night campaign aims to shine a light on the rampant spread of light pollution, hoping for 15,000 worldwide reportings between now and March 6. As of this writing, their web-site’s thermometer graphic registered maybe 500.
So lend an eye or two between 8:00 and 10:00pm (for our online readers, these same times hold true wherever you live). You’ll be comparing the number of stars you can see within Orion to a star map provided on the group’s website — www.globeatnight.org. Based on data submitted, the group will create a world-wide map of illuminating light pollution on Earth.
And if not for science, take part for the fun of the hunt. Even within city lights, a clear night should reveal Betelgeuse marking Orion’s shoulder and Rigel at his foot. Darker skies reveal the three belt stars, Alnitak, Alnilam and Mintaka. Away from the urban glow, the hunter is awash with stars, and you may even spot the string of pearls hanging from his belt, the Orion Nebula M42.