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A light echo around the star V838 Mon.
Click on image for full size
NASA, ESA, and The Hubble Heritage Team (STScI/AURA)

V838 Mon - an echo of light!

What's in a Name: The 838th variable star in the constellation Monoceros.
Claim to Fame: In early 2002, V838 Mon produced enough energy in a brief flash to illuminate the surrounding dust. Light from this outburst travels to the dust and then is reflected to Earth. Because of the indirect path, the light arrives at Earth months after light from the star that traveled directly toward Earth.
Type of Star:Erupting star. Not yet completely understood.
How Far Away: About 20,000 light years.
How Big:About 1570 times the Sun's radius. About twice the Sun's mass.
How Bright:Peak light output 600,000 times greater than the Sun.
Where to View:In the constellation of Monoceros. Not visible to the unaided eye.
When to View:Best viewed during January-March from anywhere in the world.

Last modified February 16, 2005 by Travis Metcalfe.

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