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.

2001 August 29
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AFGL 2591: A Massive Star Acts Up
Credit: C. Aspin et al., NIRI, Gemini Obs., NSF

Explanation: Young star AFGL 2591 is putting on a show. The massive star is expelling outer layers of dust-laced gas as gravity pulls inner material toward the surface. AFGL 2591 is estimated to be about one million years old -- much younger than our own Sun's 5 billion-year age -- and has created a nebula over 500 times the diameter of our Solar System in just the past 10,000 years. The above image in infrared light is one of the first from the new NIRI instrument mounted on one of the largest ground-based optical telescopes in the world: Gemini North. Sharp details are discernable that are blocked by opaque dust in visible-light images. Close inspection of the image reveals at least four expanding rings, indicating an episodic origin to the mysterious activity. AFGL 2591 lies about 3000 light years away toward the constellation of Cygnus.

Tomorrow's picture: Virtual Observatory, Real Discovery

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Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (USRA)
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