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Arcturus: Orange Giant
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What's in a Name: | Greek for "Bearkeeper". The bear is the constellation Ursa Major (the Great Bear).
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| Claim to Fame: | 4th brightest star in the sky. The reddish light of Arcturus striking a photoelectric cell marked the beginning of the 1934 Chicago World's Fair.
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| Type of Star: | Orange Giant (K2 III Spectral Class),
surface temperature 4400K. Fusing helium to carbon and oxygen in its core.
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| How Far Away: | 37 light years away
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| How Big: | 18 times larger than the sun, 4 times the sun's mass
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| How Bright: | 105 times the sun's luminosity (Mv=-0.3)
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| Where to View: | Brightest star in the constellation Bootes, the Herdsman (Star Map).
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| When to View: | April through August from Northern middle latitudes
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