ASTRO 104 Study Guide - Quiz Guide: Cosmic Distance Ladder, Right Ascension, Declination
Document Summary
Destination 3: sky from earth: properties of stars from earth. Different brightnesses and colors suggest intrinsic differences among stars. Brightness: affected by size, luminosity, and distance of the star. Color: affected by the motion of the star and the natural color of the elements burning inside (emission spectra) Diversity of stellar brightness = diversity of stellar distance: constellations and coordinates. Constellations: 6,000 visible stars, 88 constellations (specific groupings of stars, each with a 3 letter abbreviation) Zodiac: sun, moon, planets travel within their boundaries. Greek naming system: alpha, beta listed according to brightness. Numbering system: # abbreviation (76 vir) given by increasing right ascension. Ra 0 = vernal equinox: distances to stars. What is a parsecond? sin(p)=1au/d p=(1/d) p is measured in arcsec, d is measured in parsec. Parallax: shift in the apparent position of a nearby object relative to the distance background. Parallax angle: half the full angle between earth, star, earth 6 months later (tiny angle)
