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The Winter 2010 issue of The Earth Scientist includes a variety of educational resources, ranging from astronomy to glaciers. Check out the other publications and classroom materials in our online store.
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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