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Kramer
Kramer Astron. Chap 30
| Question | Answer |
|---|---|
| Brightness an object would have if it were pplaced at a distance of 10 pc; classification system for stellar brilghtness that can be calculated only when the actual distance to a star is known | Absolute magnitude |
| Classification system based on how bright a star appeaars to be; does not take distance into account so cannot indicate how bright a star actually is | Apparent magnitude |
| Describes how stars that are bound together by gravity and orbit a common center of mass | Binary star |
| Small, extremely dense remnant of a staar whose gravity is so immense that not even light can escape its gravity field | Black hole |
| Layer of the Sun's atmosphere above the photosphere and below the corona that is about 2500 km thick and has a temperature around 30,000 K at its top | Chromosphere |
| Group of stars that forms a pattern in the sky that resembles an animal, mythological character, or everday object | Constellation |
| Top layer of the Sun's atmosphere that extends from the top of the chromosphere and ranges in temperature from 1 million to 2 million K. | Corona |
| Process in which heavy atomic nuclei split into smaller, lighter nuclei | Fission |
| Process in a star's core in which lightweight hydrogen nuclei combine into heavier helium nuclei | Fusion |
| Graph that relates stellar characteristics-class, mass, temperature, magnitude, diameter, and luminosity. | Hertzsprung-Russell diagram |
| Energy output from the surface of a star per second; measured in watts | Luminosity |
| In an H-R diagram, the broad, diagnonal band that includes about 90 percent of all stars and runs from hot, luminous stars in the upper-left corner to cool, dim stars in the lower-right corner | Main sequence |
| Large cloud of interstellar gas and dust that collapses on itself, due to its own gravity, and forms a hot, condensed object that will become a new star | Nebula |
| Collapsed, dense core of a star that forms quickly while its outer layers are falling inward, has a raius of about 10 km, a mass 1.5 to 3 times that of the Sun, and contains only neutrons | Neutron Star |
| Apparent positional shift of an object caused by the motion of the observer | Parallax |
| Lowest layer of the Sun's atmosphere that is also its visible surface, has an averge temperature of 5800 K, and is abut 400 km thick | Photosphere |
| Arc of gas ejected from the chromosphere, or gas that condenses in the Sun's inner corona and rains back to the surface, that can reach temperatures over 50,000 K and is associated with sunspots | Prominence |
| Hot, condensed object at the center of a nebula that will become a new star when nuclear fusion reactions begin | Protostar |
| Violent eruption of radiation and particles from the Sun's surface that is associated with sunspots. | Solar flare |
| Wind of charged particles that flows throughoutthe solar system and begins as gas flowing outward from the Sun's corona at high speeds | Solar wind |
| Arrangement of visible light ordered according to wavelength | Spectrum |
| Dark spot on the surface of the photosphere that typically lasts two months, occurs in pairs, and has a penumbra and an umbra. | Sunspot |
| Massive explosion that occurs when the outer layers of a star are blown off | Supernova |