Term
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Definition
| parallax of one ar sec--3.26 light years |
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Term
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Definition
| amount of stars moving across they sky--most are too far awy to see proper motion |
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Term
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Definition
| brightness of star in a night sky |
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Term
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Definition
| each magnitude number changes by 2.5 times up or down |
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Term
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Definition
| how bright star would appear at 10 parsecs |
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Term
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Definition
*Tells the star surface temperature O= 30,000 k B= 10,000-30,000k A= 7,500-10,000k F=6,000k-7,500k G= 5,000k-6,000k K= 3,500k-5,000k M= 3,500k |
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Term
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Definition
| the more massive the star the brighter it is |
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Term
| Radius Luminosity--Temperature Relationship |
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Definition
| to truly know the brightness of a star you need to know size and temp |
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Term
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Definition
1) main sequence- running from upper left to lower right 2) supergiants- stars in upper right--very large and bright 3) Giants- smaller in radius and lower in luminosity 4) White dwarfs- lower left, small in radius and appear in white color |
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Term
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Definition
| can see the two stars and used to get masses |
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Term
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Definition
| cannot see the companions but spectrum tells them they are there |
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Term
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Definition
| two stars that block each others light--easy to measure masses of stars |
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Term
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Definition
| two stars that block each others light--easy to measure masses of stars |
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Term
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Definition
I- Supergiants II- Bright giants III- Giants IV- Subgiants V- Main sequence stars |
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Term
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Definition
Round, old stars, 10,000-1million stars, few heavy, Hallo of Galaxy, in a ball 60-150 light years |
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Term
Main sequence turnoff point |
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Definition
| star leaves main sequence as it gets old |
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