Cometary Globule CG4

Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2015 March 6
Cometary Globule CG4
Image Credit & Copyright: CEDIC Team - Processing: Christoph Kaltseis Explanation: The faint and somehow menacing cometary globule CG4 reaches through the center of this deep southern skyscape. About 1,300 light-years from Earth toward the constellation Puppis, its head is about 1.5 light-years in diameter and its tail about 8 light-years long. That's far larger than the Solar System's comets that it seems to resemble. In fact, the dusty cloud contains enough material to form several Sun-like stars and likely has ongoing star formation within. How its distinctive form came about is still debated, but its long tail trails away from the Vela Supernova remnant near the center of the Gum Nebula, while its head could represent the rupture of an originally more spherical cloud. Still, the edge-on spiral galaxy also near picture center is not actually being threatened by CG4. The galaxy lies in the distant background more than 100 million light-years away.

 

The Clouds of Orion the Hunter

Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2015 March 16
The Clouds of Orion the Hunter
Image Credit & Copyright: Rogelio Bernal Andreo Explanation: Cradled in cosmic dust and glowing hydrogen, stellar nurseries in Orion the Hunter lie at the edge of giant molecular clouds some 1,500 light-years away. Spanning about 30 degrees, this breath-taking vista stretches across the well-known constellation from head to toe (left to right) and beyond. At 1,500 light years away, the Great Orion Nebula is the closest large star forming region, here visible just right and below center. To its left are the Horsehead Nebula, M78, and Orion's belt stars. Sliding your cursor over the picture will also find red giant Betelgeuse at the hunter's shoulder, bright blue Rigel at his foot, the Witch Head Nebula above -- and illuminated by -- Rigel, and the glowing Lambda Orionis (Meissa) nebula on the left, near Orion's head. Of course, the Orion Nebula and bright stars are easy to see with the unaided eye, but dust clouds and emission from the extensive interstellar gas in this nebula-rich complex, are too faint and much harder to record. In this mosaic of broadband telescopic images, additional image data acquired with a narrow hydrogen alpha filter was used to bring out the pervasive tendrils of energized atomic hydrogen gas like in the arc of the giant Barnard's Loop.

Tomorrow's picture: big dipper enhanced

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