astro quiz

Question 1
Which of the following is not a line of evidence supporting the hypothesis that our Moon formed as a result of a giant impact?

The Pacific Ocean appears to be a large crater - probably the one made by the giant impact.
Question 3
Which of the following best explains why we can rule out the idea that planets are usually formed by near-collisions between stars?

Stellar near-collisions are far too rare to explain all the planets now known to orbit nearby stars.
Question 4
According to our present theory of solar system formation, which of the following objects now reside quite far from the place where they formed originally?

Oort cloud comets
Question 5
What is the primary reason that astronomers suspect that some jovian moons were captured into their current orbits?

Some moons have orbits that are "backwards" (compared to their planet's rotation) or highly inclined to their planet's equator.
Question 6
The region of our solar system between Mercury and Mars has very few asteroids, while the region between Mars and Jupiter has many asteroids. Based on what you have learned, what is the most likely explanation for the lack of asteroids between Mercury and Mars?

There were very few planetary leftovers in this region, because most of the solid material was accreted by the terrestrial planets as the planets formed.
Question 7
Suppose you find a rock that contains 10 micrograms of radioactive potassium-40, which has a half-life of 1.25 billion years. By measuring the amount of its decay product (argon-40) present in the rock, you conclude that there must have been 80 micrograms of potassium-40 when the rock solidified. How old is the rock?

3.75 billion years
Question 8
According to our theory of solar system formation, which law best explains why the solar nebula spun faster as it shrank in size?

The law of conservation of angular momentum
Question 9
What is the primary basis upon which we divide the ingredients of the solar nebula into four categories (hydrogen/helium; hydrogen compound; rock; metal)?

The temperatures at which various materials will condense from gaseous form to solid form.

Question 10
About 2% of our solar nebula consisted of elements besides hydrogen and helium. However, the very first generation of star systems in the universe probably consisted only of hydrogen and helium. Which of the following statements is most likely to have been true about these first-generation star systems?

There were no comets or asteroids in these first-generation star systems.

Question 1

According to our present theory of solar system formation, which of the following best explains why the solar nebula ended up with a disk shape as it collapsed?
It flattened as a natural consequence of collisions between particles in the nebula

Question 3

According to our present theory of solar system formation, how did Earth end up with enough water to make oceans?
The water was brought to the forming Earth by planetesimals that accreted beyond the orbit

Question 5

According to our present theory of solar system formation, which of the following statements about the growth of terrestrial and jovian planets is not true?
The jovian planets began from planetesimals made only from ice, while the terrestrial planets began from planetesimals made only of rock metal

Question 6

How do scientists determine the age of the solar system?
Radiometric dating of meteorites

Question 7

According to present understanding, which of the following statements about the solar wind is not true?
It is even stronger today than it was when the Sun was young.

Question 9

According to our theory of solar system formation, which law best explains why the central regions of the solar nebula got hotter as the nebula shrank in size?
The law of conservation of energy

Question 6
What is the primary reason that astronomers suspect that some jovian moons were captured into their current orbits?

Some moons have orbits that are "backwards" (compared to their planet's rotation) or highly inclined to their planet's equator.
Question 8
According to our present theory of solar system formation, how did Earth end up with enough water to make oceans?

The water was formed by chemical reactions among the minerals in the Earth's core.