Vocab
Across
- 3. a region of cosmic gas and dust formed from the cast off outer layers of a dying star
- 7. leftover energy from the Big Bang
- 10. tide with the largest daily tidal range, which occurs when the Sun, Earth, and Moon line up with each other
- 12. the rise and fall of sea levels caused by the gravitational attraction of the Moon and the Sun
- 13. what stars like the sun become after they have exhausted their nuclear fuel
- 17. huge celestial bodies made mostly of hydrogen and helium that produce light and heat from the churning nuclear forges inside their cores
- 20. when the tide is at its lowest elevation
- 21. tide with the smallest daily tidal range; occurs when the Sun, Earth, and the Moon form a 90-degree angle
- 22. the Sun together with the group of celestial bodies that are held by its attraction and revolve around it
- 24. a galaxy exhibiting a central nucleus from which extend curved arms of higher luminosity
- 25. the four natural divisions of the year based on changes in temperature due to the varying amounts of sunlight received caused by the tilt of Earth during its revolution
- 26. large cloud of gas and dust that contracts under gravitational force and breaks apart into smaller pieces, each of which will collapse to form a star
- 27. graph in which the absolute magnitude of stars are plotted against their temperatures
- 30. when the left half of the Moon is illuminated and the lunar cycle is in the waning phase
- 33. the movement of one object around a center or another object
- 34. a young star forming from a collapsing region within a molecular cloud
- 35. distance light travels in a year
- 37. states that about 12 billion to 15 billion years ago, the universe began with a huge, fiery explosion
- 39. a band of stars on a Hertzsprung-Russell (HR) diagram that represents the stages a star goes through during most of its life
- 40. a star with a large radius for its mass and temperature, resulting in high brightness
Down
- 1. a huge collection of gas, dust, and billions of stars and their solar systems, all held together by gravity
- 2. the lunar phase when the Moon is between the Sun and the Earth and none of the illuminated portion is seen from Earth
- 4. an area of such immense gravity that nothing, not even light, can escape from it
- 5. a galaxy with no identifiable shape or structure, mostly made of young stars.
- 6. when the tide is at its greatest elevation
- 8. the slant of Earth’s axis
- 9. all of space and everything in it including stars, planets, and galaxies
- 11. an invisible form of matter that does not emit any detectable electromagnetic energy of its own
- 14. an attractive force that exists between all objects that have mass
- 15. the lunar phase when Earth is between the Sun and Moon and all of the illuminated portion is seen from Earth
- 16. the imaginary line through Earth that extends from the North Pole to the South Pole and is the center of Earth’s rotation
- 18. when the right half of the Moon is illuminated and the lunar cycle is in the waxing phase
- 19. an invisible form of energy that creates a repulsive force causing the universe to expand
- 22. the two days of the year when the noon sun reaches its highest or lowest point in the sky
- 23. the spiral galaxy of which in the Sun and the solar system are a part.
- 28. an enormous explosion that destroys a star
- 29. day and night are the same length because neither hemisphere is tilted toward the sun
- 31. an oval shaped galaxy, made of old stars and does not have much gas or dust
- 32. the shift to a different wavelength
- 36. a curved path followed by a satellite as it revolves around an object
- 38. the path an object follows as it moves around another object