Question

1. most planetary systems discovered thus far have planets that resemble those in the solar system, with rocky planets close to their stars and large planets like the jovian planets farther out, all in nearly circular orbits around their stars. a. true b. false 43. pluto has moons but no rings. a. true b. false 44. a shooting star is a meteoroid. a. true b. false 45. the asteroid belt is debris from the cambrian explosion. a. true b. false 46. a comet with a period of 10,000 years comes from the kuiper belt. a. true b. false 47. pluto is sometimes closer to the sun than neptune. a. true b. false 48. an astronaut walking on a comet could easily float off into space. a. true b. false 49. panspermia refers to primitive alien life from other planets drifting across space to seed life on the earth a. true b. false 50. small objects (a few centimeters in size) are called “fireballs” if they hit the earth’s upper atmosphere. a. true b. false

Explanation:

1. Most exoplanetary systems have a wide variety of configurations and not all resemble the Solar - System.
2. Pluto has five known moons and no rings.
3. A shooting star is a meteoroid that enters the Earth's atmosphere and burns up.
4. The asteroid belt is leftover debris from the early formation of the Solar - System, not from the Cambrian Explosion.
5. Comets with long periods (like 10,000 years) typically come from the Oort Cloud, not the Kuiper Belt.
6. Pluto has a highly elliptical orbit and is sometimes closer to the Sun than Neptune.
7. Comets have very low gravity, so an astronaut could easily float off.
8. Panspermia is the hypothesis that life exists throughout the Universe and is distributed by meteoroids, asteroids, etc.
9. Larger meteors (not just a few centimeters) that are particularly bright when they hit the Earth's upper atmosphere are called fireballs.

Answer:

1. B. FALSE
2. A. TRUE
3. A. TRUE
4. B. FALSE
5. B. FALSE
6. A. TRUE
7. A. TRUE
8. A. TRUE
9. B. FALSE