Question

1.

All the planets orbit the Sun in the same direction.
This is strong evidence that:

Group of answer choices

None of these is correct. We do not have any idea yet why the planets are orbiting in the same direction.

the solar system resulted from the collision of two medium-sized stars.

after the planets formed, collisions between them eventually caused them all to move in the same direction.

the planets were formed elsewhere in the galaxy and were later captured by the Sun.

the solar system formed from a rotating cloud of gas that collapsed to form the Sun and planets.

2.

As the solar nebula contracted, much of its material formed into a disk. This happened because:

Group of answer choices

the nebula was cool so everything fell toward the center very rapidly.

Kepler’s laws did not hold in the early solar system.

the nebula always had a disk shape.

the nebula was spinning.

the nebula was not spinning.

3.

Protoplanets are thought to coalesce from planetesimals about 1 km in diameter. Why do these planetesimals stick together when they collide?

Group of answer choices

There is gravitational attraction between the planetesimals.

A sticky surface material causes them to adhere.

The planetesimals are electrically charged, and electric forces make them attract each other.

Chemical bonds hold the planetesimals together.

4.

Is there any debris left over from the small particles that formed planetesimals, which in turn coalesced into the planets?

Group of answer choices

No, all the material was used up in forming the planets.

Yes, there is debris left over in the form of dust, meteoroids, asteroids, and comets.

Yes, but we cannot see it because of its small size.

No, the material left over was all ejected from the solar system by Jupiter and Saturn.

No, the material left over was all burned up in the Sun.

5.

What property of the early solar nebula helped to define the formation of the terrestrial and the jovian planets?

Group of answer choices

The temperature distribution within the nebula

The distribution of hydrogen in the nebula

The distribution of silicates in the nebula

The mass of the Sun

The rotation of the nebula

Answer 1

1. All the planets orbit the Sun in the same direction. This is strong evidence that the solar system formed from a rotating cloud of gas that collapsed to form the Sun and planets.

2. As the solar nebula contracted, much of its material formed into a disk. This happened because the nebula was spinning.

3. Protoplanets are thought to coalesce from planetesimals about 1 km in diameter. These planetesimals stick together when they collide because There is gravitational attraction between the planetesimals.

4. The debris that was left over from the small particles that formed planetesimals in turn coalesced into the planets. Yes, there is debris left over in the form of dust, meteoroids, asteroids, and comets.

5. The distribution of silicates in the nebula helped to define the formation of the terrestrial and the jovian planets.