Details Title: Chapter 11 Description: Surveying the stars Total Flash Cards: 17 Created: 04/21/2008 11:20:07		New Users: To study from this flashcard set, or to create your own your own study flash cards, REGISTER HERE. Existing Users: CLICK HERE. Additional Physics Flashcards
Cards in this set: Term Parsec Definition parallax of one ar sec--3.26 light years Term Proper Motion Definition amount of stars moving across they sky--most are too far awy to see proper motion Term Apparent brightness Definition brightness of star in a night sky Term Magnitude scale Definition each magnitude number changes by 2.5 times up or down Term Absolute mag Definition how bright star would appear at 10 parsecs Term Spectral Classes 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 Term Mass Luminosity Definition the more massive the star the brighter it is Term Radius Luminosity--Temperature Relationship Definition to truly know the brightness of a star you need to know size and temp Term HR diagram 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 Term Visual Binaries Definition can see the two stars and used to get masses Term Spectroscopic Binaries Definition cannot see the companions but spectrum tells them they are there Term Spectroscopic Binaries Definition two stars that block each others light--easy to measure masses of stars Term Eclipsing Binaries Definition two stars that block each others light--easy to measure masses of stars Term Luminosity Classes Definition I- Supergiants II- Bright giants III- Giants IV- Subgiants V- Main sequence stars Term Globular Definition Round, old stars, 10,000-1million stars, few heavy, Hallo of Galaxy, in a ball 60-150 light years Term Main sequence turnoff point Definition star leaves main sequence as it gets old Term Definition