Astronomy Picture Of The Day Explore the cosmos Every day, a new image or photograph of the fascinating universe is presented along with a short explanation by an astronomer. 2021 October 13
NGC 7822 - Cosmic Question Mark
Yizhou Zhang, Image Credit and Copyright
Explanation: Although it may seem like a large cosmic question mark, the real question is how do the bright gas and the dark dust tell the story of the nebula’s history in star formation. The glowing region NGC7822, a star-forming region that lies approximately 3,000 light years away from the northern constellation Cepheus is located at the edge of a huge molecular cloud. This colorful and detailed skyscape highlights the bright edges and dark shapes within the nebula. This mosaic of 9 panels was created over 28 nights using a Texas small telescope. It includes data from narrowband filters that map emission from atomic oxygen and hydrogen into blue, green and red hues. The Hubble palette is well-known for its emission line and combination of colors. Energetic radiation from central hot stars powers the atomic emission. Their strong winds and radiation create and erode denser pillar forms and open up a cavity light-years across central cloud. Although stars could still form within the pillars due to gravitational collapse, once the pillars have been eroded away any remaining stars will be cut off from the star material they contain. At the distance of NGC7822, this field of view is more than 40 light-years wide.
