Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Astronomy part 2
| Term | Definition |
|---|---|
| photosphere | luminous visble surface of sun, shallow layer of strong ionized gases |
| chromosphere | gaseous envelope surrounding a star (on the sun: outside of photosphere) |
| corona | faintly luminous envelope outside of sun's chromosphere, inner part made of highly ionized elements |
| solar wind | emanation from sun's corona, flow of charged particles, interacts with magnetic field of earth and other planetry bodies |
| sunspot | dark patch appears periodically on the surface of the sun, affects terrestrial magnetism and other phenomena |
| prominence | flamelike eruption of relatively cool, high-density gas from sun's chromosphere into corona |
| solar flare | sudden burst or flame |
| aurora | radiant emission from upper atmosphere happens sporadically over middle and high of both hemispheres looks like limunous bands |
| nuclear fusion | reaction in the nucleaus of light atoms formed to make a heavier atom |
| constellation | any group of stars to which a name has been given |
| binary star | two stars that revolve about their common center of mass |
| light year | unit of astronomical distance equivalent to distance that light travels in 1 year |
| apparent magnitude | how an observor on earth sees the magnitude of a star |
| absolute magnitude | how a hypothetical observer would view the magnitude of a star (viewer is light years away) |
| main sequence star | stary laying on a diagonal band that extends from hot stars to cool stars |
| red giant | star in intermediate stage of evolution, large volume, low surface temperature, reddish hue |
| supergiant | star whose diameter is more than 100 times the size of the sun's, extremely bright |
| cepheid variable | variable star, changes in brightness are due to alternate contractions and volume changes |
| nova | a star that suddenly becomes 100 times brighter and then fades back to its original intensity |
| nebulae | a cloud on intersellar gas and dust |
| hertzsprung russell diagram | graph showing absolute magnitude plotted against surface temperature for stars |
| protostar | early stage in evolution of star |
| supernova | explosion of star |
| white dwarf | star about the size of earth, has underagone gravitational collapse and is in final stage of evolution for low mass stars |
| neutron star | extremely dense compact star, primarly made of neutrons |
| pulsar | one of several hundred celestial bodies, rapidly rotating neutron stars, emit pulses of radiation, |
| black hole | theoretical massive object at beginning of universe |
| galaxy | system of stars held together by mutual gravitation, isolated from similar systems |
| hubble's law | velocity of recession of distant galaxies from our own is proportional to their distance from us |
| big bang theory | a theory that deduces a cataclysmic birth of the universe |
Created by:
3083291
Popular Earth Science sets