Astronomy/Stars & Galaxies Crossword

12345678910111213141516171819202122232425262728293031323334
Across
  1. 1. Stars that pulsate radially, varying in both temperature and diameter, to produce brightness changes with a well-defined stable period and amplitude.
  2. 4. An explosion that marks the final stage of stellar evolution.
  3. 8. The classification of stars according to their temperatures using the characteristics of their spectra.
  4. 10. The distance from the center of a black hole to its event horizon.
  5. 12. A star that experiences a sudden outburst of radiant energy, temporarily exponentially increasing its luminosity.
  6. 13. A star of extremely high density composed almost entirely of neutrally charged subatomic particles.
  7. 16. A spherical collection of stars that orbits a galactic core as a satellite.
  8. 17. A variable radio source of small angular size that emits very rapid radio pulses in very regular periods.
  9. 19. A low-mass star that has exhausted most or all of its nuclear fuel and has collapsed to a very small size.
  10. 20. A measure of the observed light received from a star or other object.
  11. 22. The apparent displacement of a nearby star caused by the revolution of the Earth around the sun.
  12. 23. A theoretical point of zero volume and infinite density to which any black hole must collapse.
  13. 26. A large assemblage of stars, gas, dust, and dark matter orbiting a common center.
  14. 27. The outermost extent of a galaxy with a sparse distribution of stars.
  15. 28. A star of large luminosity and radius.
  16. 29. A large assemblage of stars without radial symmetry.
  17. 30. Two stars that revolve around each other.
  18. 31. An object of very high redshift that looks like a star but is extragalactic and highly luminous
  19. 32. Middle-age stars that can be found running diagonally through the middle of an HR diagram.
  20. 34. The central part of a galaxy.
Down
  1. 1. The upper boundary to the mass of a white dwarf.
  2. 2. A star of very high luminosity and relatively low temperature.
  3. 3. A flattened, rotating, large assemblage of stars with pinwheel-like arms of interstellar material and stars winding out from its nucleus.
  4. 5. Large, cold, interstellar clouds with large diameters where massive stars form.
  5. 6. One of the 107 galaxies, nebulas, star clusters, and other deep sky objects classified with an M followed by a number.
  6. 7. A plot of luminosity against surface temperature or spectral type for a group of stars also called an HR diagram.
  7. 9. An assemblage of stars, oval in shape, that contains no conspicuous interstellar material.
  8. 11. A collapsed, massive body whose escape velocity is equal to or greater than the speed of light.
  9. 14. A measure of the luminosity of an object like a star.
  10. 15. An object, midway in size between a planet and a star, with a mass about 1/100 that of the sun.
  11. 18. The rate at which an object must travel in order to break free of the influence of gravity.
  12. 21. A cloud of interstellar gas or dust
  13. 24. The main portion of a galaxy. Consists of a nucleus, bulge, and spiral arms.
  14. 25. A morphological classification scheme for galaxies. Often described as a tuning fork, after the shape of the diagram created from it.
  15. 33. The surface at which the escape velocity of a collapsing star is equal to the speed of light.