Exam 7: The Formation of Planetary Systems

If an astronomer on a planet orbiting a nearby star observed the Sun when Neptune was transiting in front of the Sun, how would the Sun's brightness change? Note that the radius of Neptune is 2.5 * 10⁷ m.

In order for two clumps of dust to stick together in an accretion disk, they must collide at roughly

A refractory material is a material that

Astronomers have used radial velocity monitoring to discover

Why did the terrestrial planets lose their primary atmospheres?

As the radius, r, of extrasolar planets increases, we expect the amount of light they block from their parent star to change by a factor of ________.

What is a secondary atmosphere?

Which is the best description of a moon?

What property of an extrasolar planet can be determined directly from the Doppler effect data shown in the figure below? What other properties of the planet can then be determined if the mass of the central star is known?

What happens to the rotation speed of a slowly rotating cloud as it collapses to form a stellar system? Why does this occur?

Approximately how massive are most of the extrasolar planets that have been discovered using the Doppler effect, and which planet in our Solar System is similar in mass? Why is the Doppler effect method more likely to find massive (rather than low-mass) planets and planets that are close to their stars?

Which of the following is a terrestrial planet?

The atmosphere of which of these Solar System bodies is primary (as opposed to secondary) in origin?

What have astronomers and geologists studied to arrive at the same conclusions about Earth's origins?

If an interstellar cloud having a diameter of 10¹⁶ m and a rotation period of 1 million years were to collapse to form a sphere that had the diameter of our Solar System (approximately 40 AU), what would its rotation period be? Assume the cloud's total mass and angular momentum did not change.

What evidence do we have that planetary systems are common in the universe?

Why did the planetesimals in the asteroid belt never coalesce into a planet?

What evidence do we have that the accretion disk that formed the Solar System was initially much denser near its center?

How do astronomers explain the basic difference in composition between the inner planets and the outer planets?

The object shown in the figure below is a ________ and the dark circles, or "lanes," are mostly likely due to ________.