Question

section 23.4 assessment
reviewing concepts

1. where are most asteroids located?
2. describe the structure of a comet.
3. where do short - period comets come from? what about long - period comets?
4. meteoroids originate from what three sources?

critical thinking

1. comparing and contrasting compare and contrast a meteoroid, meteor, and meteorite.
2. predicting what do you think would happen if earth passed through the tail of a comet?

Explanation:

1. Most asteroids are located in the asteroid - belt between Mars and Jupiter.
2. A comet has a nucleus (solid core), a coma (cloud of gas and dust around the nucleus), and a tail (formed when near the Sun, pointing away from the Sun).
3. Short - period comets come from the Kuiper Belt, long - period comets from the Oort Cloud.
4. Meteoroids originate from asteroids, comets, and the Moon or Mars (ejected by impacts).
5. A meteoroid is a small rocky or metallic body in space. A meteor is a meteoroid that enters Earth's atmosphere and burns up, creating a streak of light. A meteorite is a meteoroid that survives the passage through the atmosphere and hits the Earth's surface.
6. If Earth passed through the tail of a comet, there could be an increase in meteors (a meteor shower), and the gases and dust in the tail could potentially affect Earth's upper atmosphere, but likely have minimal long - term or catastrophic effects as the tail is very tenuous.

Answer:

1. In the asteroid - belt between Mars and Jupiter.
2. It has a nucleus, a coma, and a tail.
3. Short - period comets come from the Kuiper Belt; long - period comets come from the Oort Cloud.
4. Asteroids, comets, and the Moon or Mars (ejected by impacts).
5. A meteoroid is in space, a meteor burns up in the atmosphere, a meteorite hits the Earth's surface.
6. There could be a meteor shower and possible minor effects on the upper atmosphere.