GLY 1001 Earth Science
Name:________________
Chapter 24 Part K: Key Terms
Fill in
the blanks with the word(s) that best fit the description:
1. _______________ The apparent brightness of a star if it were viewed from a distance of 10 parsecs (32.6 light years). Used to compare the true brightness of stars.
2. _______________
The brightness of a star when viewed from Earth.
3. _______________ A galaxy having straight arms extending from its nucleus.
4. _______________ The theory that proposes that the universe originated as a single mass which subsequently exploded.
5. _______________ a massive star that has collapsed to such a small volume that the gravity prevents the escape of all radiation.
6. _______________ A cloud of glowing gas excited by ultraviolet radiation from hot stars.
7. _______________ A cloud of interstellar dust that obscures the light of more distant stars and appears as an opaque curtain.
Degenerate matter -
9. _______________ A galaxy that is round or elliptical in outline. It contains little gas and dust, no disk, or spiral arms, and few, hot bright stars.
10. _______________ A gaseous nebula that derives its visible light from the fluorescence of ultraviolet light from a star in or near the nebula.
11. _______________ A star that varies in brightness.
12. _______________ A system of galaxies containing from several to thousands of member galaxies.
13. _________________________ A plot of stars according to their absolute magnitudes and spectral types.
14. _______________ Relates the distance to a galaxy and its velocity.
15. _______________ The conversion of hydrogen through fusion to form helium.
16. _______________ Dust and gases found between stars.
17. _______________ A galaxy that lacks symmetry
18. _______________Light-year The distance light travels in a year, about six trillion miles.
19. _______________Local Group The cluster of 20 or so galaxies to which our galaxy belongs.
20. _______________Magnitude A number given to a celestial object to express its relative brightness.
22. _______________ A sequence of stars on the Hertzsprung-Russell Diagram, containing the majority of stars, that runs diagonally from upper left to lower right.
23. _______________ A cloud or stellar gas and/or dust.
24. _______________ A star of extremely high density composed entirely of neutrons.
25. _______________ - A star that explosively increases in brightness.
26. _______________ A shell of incandescent gas expanding from a star.
27. _______________ A collapsing cloud of gas and dust destined to becomes a star.
28. _______________ A variable radio source of small size that emits radio pulses in very regular periods.
29. _______________- A variable star that pulsates in size and luminosity.
30. _______________ A large, cool
star of high luminosity, a star occupying the upper-right portion of the Hertzsprung-Russell
Diagram.
31. _______________ A relatively dense dust cloud in interstellar space that is illuminated by starlight.
32. _______________ A flattened, rotating galaxy with pinwheel-like arms of interstellar material and young stars winding out from its nucleus.
33. _______________ A measure of stellar distance.
34. _______________ A very large star of high luminosity.
35. _______________ An exploding star that increases in brightness many thousands of times.
36. _______________ A star that has exhausted most or all of its nuclear fuel and has collapsed to a very small size; believed to be near its final stage of evolution.
Chapter 24 Word
List
Absolute magnitude Apparent magnitude Barrel spiral galaxy Big bang Black hole Bright nebula Dark nebula Degenerate matter Elliptical galaxy Emission nebula Eruptive variables Galactic cluster |
Hertzsprung-Russell (H-R) diagram Hubbles law Hydrogen burning Interstellar dust Irregular galaxy Light-year Local Group Magnitude Main-sequence stars Nebula Neutron star |
Nova Planetary nebula Protostar Pulsar Pulsating variables Red giant Reflection nebula Spiral galaxy Stellar parallax Supergiant Supernova White dwarf |