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Alpha Centauri - The Sun's Twin - Windows to the Universe

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Alpha Centauri - The Sun's Twin


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What's in a Name: Sometimes called Rigel Kentaurus meaning "foot of the Centaur" in Arabic.
Claim to Fame: Member of the triple star system closest to our sun. 3rd brightest star in the sky (apparent visual magnitude = -0.3).
Type of Star: Yellow-Orange Main Sequence star (G2 V Spectral Class).
How Far Away: 4.3 light years away
How Big: About the same size as the sun
How Bright: 40% brighter than the sun. Absolute visible magnitude Mv = +4.4
Where to View: Located in the constellation Centaurus, the Centaur (Star Map)
When to View: Centaurus is never in the sky viewed from middle northern latitudes (around 40 degrees). As you travel south on the Earth's surface and pass below the equator, you will definitely see it from time to time.

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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part by the National Science Foundation and NASA, our Founding Partners (the American Geophysical Union and American Geosciences Institute) as well as through Institutional, Contributing, and Affiliate Partners, individual memberships and generous donors. Thank you for your support! NASA AGU AGI NSF