22.15: The Solar System- Challenge 3
- Page ID
- 6176
- 1. The outer planets are ___.
- Jupiter, Saturn, Uranus, and Neptune
- 2. The inner planets are ___.
- Mercury, Venus, Earth, and Mars
- 3. Compared to Earth, Mercury has ___ years and ___ days.
- short; long
- 4. Mercury's large core is mostly liquid ___.
- iron
- 5. Mercury is ___ because it has such a large core.
- dense
- 6. Venus is sometimes referred to as the ___.
- Morning Star
- 7. Surface temperatures on Venus reach up to ___.
- 465 degrees Celsius
- 8. The atmospheric pressure on Venus is ___ times greater than the atmospheric pressure on Earth.
- 90
- 9. The dark areas of the Moon are called ___.
- maria
- 10. The footprints of astronauts on the Moon cannot be erased by weathering and erosion, but a ___ could destroy them.
- meteorite impact
- 11. Maria cover about ___ percent of the Moon's surface.
- 16
- 12. Mars is nicknamed the Red Planet because of the ___ in its soil.
- iron oxide
- 13. Water cannot stay in liquid form for long on Mars because ___.
- the atmospheric pressure is too low
- 14. Mars has ___ moons, named ___ and ___.
- two; Phobos; Deimos