Across
- 5. 75 percent of the visible universe is made up of ________ and 25 percent is helium.
- 7. The cyclic model indicates that our universe consists of _______ dimensions.
- 8. ___________ _______________ is the mysterious force that scientists think is driving the universe's current accelerating expansion.
- 11. The discovery of the cosmic microwave background radiation was found because no matter where the telescope was pointed, astronomers received __________.
- 12. A point of infinite density and temperature is called a _____
- 13. The universe is expanding at an _____ rate.
Down
- 1. The earliest stars began shining after 300 ______ years.
- 2. In the steady state theory, new particles were continually being ________.
- 3. How do heavier elements get spread throughout the universe?
- 4. The scientists that study the Big Bang theory are called ___________.
- 6. The picture gotten by the Wilkinson Microwave Anisotropy Probe (WMAP) satellite shows the universe at 4.5 _____ years old.
- 9. After the universe underwent inflation, it was probably filled with a hot, dense _______.
- 10. Because you know that space is expanding, you can tell that the universe was once_______.