Exam 9: Asteroids, Comets, and Dwarf Planets: Their Nature, Orbits, and Impacts

Refer to the following scenario for the questions below. Lost in the Solar System: You have been abducted by an alien being. After performing experiments on you, the alien gives you a "life- support belt", allowing you to survive in any environment, and dumps you somewhere in the solar system. Each question below gives a brief description of a place where you were left by the alien. Identify your location. Be as specific as possible. Include a brief explanation for your answer. -You find yourself in a maelstrom, whipped by winds gusting at 10,000 km/hr, rising and falling in convective currents. On the rare occasions when you can assess your surroundings, you notice a horizon that seems to go on "forever" (or, at least, much farther than the horizon on Earth), and no solid surface anywhere. You get a glimpse of several large moons. The Sun races through your sky, requiring only about 5 hours to rise nearly due east, cross the meridian at an altitude of about 55° in the north, and then set due west.

Visiting comets and asteroids: In recent years, several space probes have been sent to comets and asteroids to physically interact with them. Briefly describe three of these missions, and compare how each allows astronomers to better study the composition of these objects.

What do astronomers mean when they refer to "gaps" in the asteroid belt between Mars and Jupiter?

Which direction do a comet's dust and plasma tails point?

The last major dinosaurs were wiped out as a consequence of a major impact with the Earth about 65 million years ago. All but one of the following statements would be regarded as evidence for this claim.

Classification in Science: Usually, the first task of any science is to classify the available observations. Often, the initial classification scheme reflects the historical order of discovery in addition to nature itself. In this question, we will use our solar system as an example. Make a complete list of all of the solar system components that you have studied in the last three chapters. Then try to place this list in historical order of discovery. For example, start your list with the Sun, Moon, Earth, and 5 "classical" planets, which have been known for all of human history, and end your list with Eris, the largest currently known Kuiper Belt object. Can you see the historical order of discovery reflected in the classification of objects on your list? Have there been occasions when this classification scheme has been revised? Finally, does the classification scheme for the solar system introduce any artificial divisions, making strict categories from objects with a continuous range of properties?

What evidence led astronomers to conclude that the Oort cloud is a spherical distribution of comets?

In what way(s)does this figure give a poor representation of the asteroid belt?

What is Pluto's moon Charon thought to have in common with our own Moon?

Gaps in the asteroid belt (often called Kirkwood gaps)are caused by .

Suppose we discover a new comet on an orbit that brings it closer to the Sun than Mercury every 125 years. What can we conclude?

Refer to the following choices to answer the questions below. Choose the answer that best describes the chemical composition of the object. -a Kuiper- belt object

What part of a comet always points most directly away from the Sun?

Refer to the following choices to answer the questions below. Choose the answer that best describes the chemical composition of the object. -Comet Hale- Bopp

What would be the consequence(s)of more frequent collisions between planets and asteroids?

What is Charon?

Which of the following statements about comets and asteroids is true?

Processed meteorites with high metal content probably are

On average, how often do impacts large enough to produce mass extinction on the Earth occur?

How was Pluto's surface mapped?