Ch. 28. 4 - Asteroids, Comets, and Meteoroids

List the following parts of the solar system from closest to the sun to farthest from the sun: Kuiper Belt, asteroid belt, Neptune, Oort cloud.

-asteroid belt, -Neptune, -Kuiper Belt, -Oort cloud

Describe 2 differences between asteroids and comets.

1 - Most asteroids are located between the orbits of Mars and Jupiter, and most asteroids are made of rock, metal, or both. 2 - Most comets come from the Oort cloud or the Kuiper Belt, which are beyond the orbit of Neptune. Most comets are made of ice, dust, and rock.

Your friend tells you that he found a meteor in his backyard. What is wrong with your friend's statement?

A meteor is a flash of light that forms when a meteoroid burns up in Earth's atmosphere. It's impossible to "find" a meteor on the ground, because by definition a meteor is a flash of light in the sky.

How does a meteor form?

As a meteoroid flies through Earth's atmosphere, friction causes it to get hotter and eventually burn up. The burning produces a flash of light, which is a meteor.

Iron meteorites are the easiest kind of meteorite to identify. What is the most likely reason for this?

Iron meteorites look very different from any rocks on Earth. Therefore, they are easier to identify as meteorites.

When an asteroid collides with Earth, it produces effects similar to those of a large volcanic eruption. What is one way an asteroid impact might harm life on Earth?

It could throw large amounts of dust into the atmosphere. The dust could block the sun and make Earth cooler.

Suppose astronomers discovered a comet that takes about 875 years to orbit the sun. Is the comet a short-period comet or a long-period comet? Where did it probably come from?

It is a short-period comet, so it probably came from the Oort cloud.

How is the appearance of a carbon asteroid different from the appearance of an iron and nickel asteroid?

Most carbon asteroids are dark colored. Most iron and nickel asteroids are shiny and metallic looking.

Could the ion tail of a comet ever point in the opposite direction from the dust tail?

Yes, it could. When the comet is moving away from the sun, the dust tail will point back along its orbit (toward the sun), but the ion tail will point away from the sun.

meteor

a bright streak of light that results when a meteoroid burns up in Earth's atmosphere

What is the Oort cloud?

a cloud of dust and ice that lies beyond Neptune's orbit

Kuiper Belt

a region of the solar system that starts just beyond the orbit of Neptune and that contains dwarf planets and other small bodies made mostly of ice

meteoroid

a relatively small, rocky body that travels through space

comet

a small body of rock, ice, and cosmic dust that follows an elliptical orbit around the sun and that gives off gas and dust in the form of a tail as it passes close to the sun

asteroid

a small, rocky object that orbits the sun; most asteroids are located in a band between the orbits of Mars and Jupiter

Oort cloud

a spherical region that surrounds the solar system, that extends from the Kuiper Belt to almost halfway to the nearest star, and that contains billions of comets

Where are most asteroids located?

between the orbits of Mars and Jupiter, in the asteroid belt