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This drawing compares the Earth to the white dwarf, 40 Eridani B. The star is part of a triple star system about 16 light years from Earth in the constellation, Eridanus, "The River". 40 Eridani B is half the mass of the Sun with a diameter about twice that of Earth. It is very heavy for its size.
Travis Metcalfe

40 Eridani B - Burnt-Out Cinder

What's in a Name: Star designated 40 in the constellation Eridanus.
Claim to Fame: One of the first white dwarfs found. A white dwarf is the exposed extremely hot core of a star that has blown off its outer layers. Made of extremely dense material. A piece the size of a marble would weigh as much as an elephant.
Type of Star: Blue-White Color. Small hot white dwarf (Spectral Class DA4).
How Far Away: 16 light years
How Big:1/70 sun's radius (1.5 times the Earth's radius). About 1/2 the sun's mass.
How Bright:1/300 times the sun's visible brightness
Where to View: In the constellation of Auriga. Not visible to the unaided eye.
When to View: Best viewed from the Northern hemisphere during November-January.

Last modified January 31, 2005 by Travis Metcalfe.

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The Summer 2010 issue of The Earth Scientist, available in our online store, includes articles on rivers and snow, classroom planetariums, satellites and oceanography, hands-on astronomy, and global warming.

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