Astronomy and Cosmology

12345678910111213141516171819202122232425
Across
  1. 2. Small circle whose center moves around the circumference of a larger one.
  2. 4. The science of the origin and development of the universe.
  3. 8. A group of stars forming a recognizable pattern that is traditionally named after its apparent form or identified with a mythological figure.
  4. 11. Time reckoned from the motion of the earth relative to the distant stars.
  5. 12. Space Telescope
  6. 15. Nuclear reaction in which atomic nuclei of low atomic number fuse to form a heavier nucleus with the release of energy.
  7. 16. A system of millions or billions of stars, together with gas and dust, held together by gravitational attraction.
  8. 18. A statement or proposition which is regarded as being established, accepted, or self-evidently true.
  9. 19. Another term for Greenwich Mean Time.
  10. 21. The envelope of gases surrounding the earth or another planet.
  11. 23. The branch of science that deals with celestial objects, space, and the physical universe as a whole.
  12. 25. The force that attracts a body toward the center of the earth, or toward any other physical body having mass.
Down
  1. 1. natural object which is located outside of the Earth's atmosphere, such as the Moon, the Sun, an asteroid, planet, or star.
  2. 3. the star around which the earth orbits
  3. 5. A continuous area or expanse which is free, available, or unoccupied.
  4. 6. A small very dense star that is typically the size of a planet.
  5. 7. White dwarf that has cooled sufficiently to no longer emit significant heat or light.
  6. 9. A cluster of galaxies which themselves occur as clusters.
  7. 10. Discrete quantity of energy proportional in magnitude to the frequency of the radiation it represents.
  8. 13. How astronomers explain the way the universe began.
  9. 14. Numerical or other measurable factor forming one of a set that defines a system or sets the conditions of its operation.
  10. 17. An instance of one moving object or person striking violently against another.
  11. 20. A theoretical repulsive force that counteracts gravity and causes the universe to expand at an accelerating rate.
  12. 22. All of space and time and their contents, including planets, stars, galaxies, and all other forms of matter and energy.
  13. 24. One of the largest known dwarf planets in our solar system.