Astronomy Picture of the Day

Thor’s Helmet Emission Nebula
Image Credit & Copyright: Adam Block, Mt. Lemmon SkyCenter, U. Arizona

Explanation: This helmet-shaped cosmic cloud with wing-like appendages is popularly called Thor‘s Helmet. Heroically sized even for a Norse god, Thor’s Helmet spans about 30 light-years across. In fact, the helmet is more like an interstellar bubble, blown as a fast wind — from the bright star near the center of the bubble’s blue-hued region — sweeps through a surrounding molecular cloud. This star, a Wolf-Rayet star, is a massive and extremely hot giant star thought to be in a brief, pre-supernova stage of evolution. Cataloged as NGC 2359, the emission nebula is located about 12,000 light-years away toward the constellation of the Big Dog (Canis Major). The sharp image, made using broadband and narrowband filters, captures striking details of the nebula’s filamentary gas and dust structures. The blue color originates from strong emission from oxygen atoms in the nebula.

Tomorrow’s picture: Thor’s day (Thursday)

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s