ASTR 111 Chapter 7 Review Questions
What are the basic differences between terrestrial and Jovian planets? Which planets fall into each group?
Terrestrial: Small, rocky planets that are close together and close to the Sun. Mercury, Venus, Earth, and Mars. Jovian: Large gas-rich planets that are farther apart and farther from the sun. Jupiter, Saturn, Uranus, and Neptune.
What do we mean by comparative planetology? Does it apply only to planets?
We compare the worlds to one another, seeking to understand their similarities and differences. It applies to not only planets but also to moons, asteroids, and comets.
Flyby
A spacecraft on a flyby goes past a world just once and then continues on its way.
Sample Return Mission
A sample return mission makes a round trip to return a sample of the world it has studied to Earth.
Briefly describe the patterns of motion that we observe among the planets and moons of our solar system.
-All planetary orbits are nearly circular and lie nearly in the same plane. -All planets orbit the Sun in the same directions: counterclockwise as viewed from high above Earth's North Pole. - Most planets rotate in the same directions in which they orbit, with fairly small axis tilts. The Sun also rotates in this direction. - Most of the solar system's large moons exhibit similar properties in their orbits around their planets, such as orbiting in their planet's equatorial plane in the same direction as the planet rotates.
Briefly describe the overall layout of the solar system as it is shown in figure 7.1. What are the four major features of our solar system that provide clues to how it formed?
1.) Large bodies in the solar system have orderly motions. 2.) Planets fall into two major categories. 3.) Swarms of asteriods and comets populate the solar system. 4.) Several notable exceptions to these trends stand out.
Describe at least two "exceptions to the rules" that we find in our solar system.
1.) While most of the planets rotate in the same direction as they orbit, Uranus rotates nearly on its side, and Venus rotates "backwards" 2.) Similarly, while most large moons orbit their planets in the same direction as their planets rotate , many small moons have much more unusual orbits.
Orbiter
An Orbiter is a spacecraft that orbits the world it si visiting, allowing longer term study.
What are asteroids? What are comets? Describe the basic differences between the two, and where we find them in our solar system.
Asteroids are rocky bodies that orbit the sun much like planets, but they are much smaller. They are mainly found in the asteroid belt found between the orbits of Mars and Jupiter. Comets are also small objects that orbit the sun, but they are made largely of ices mixed with rock. They make occasional appearances in our solar systems.
What do we mean by hydrogen compounds? In what kinds of planets or small bodies are they major ingredients?
Compounds containing hydrogen, such as water, ammonia, and methane. These are major ingredients in Jovian planets.
What is the Kuiper Belt? What is the Oort Cloud? How do the orbits of comets differ in the two regions.
Kuiper Belt is the donut shaped region beyond the orbit of Neptune. It contains at least 100,000 icy objects that are more than 100 kilometers in diameter. The Oort Cloud is the second cometary region, it is much farther from the sun and may contain a trillion comets. These comets are randomly inclined to the ecliptic plane, giving them a roughly spherical shape.
What would the solar system look like to your naked eye if you could view it from beyond the orbit of Neptune?
Not much , because of the distance between planets they are very small. They would only be small pin point of light in the sky.
What kind of object is Pluto? Explain.
Pluto is a Dwarf Planet. Which means it was too small to qualify as an official planet but large enough to be round in shape.
Lander or Probe
These spacecraft are designed to land on a planet's surface or probe a planet's atmosphere by flying through it. Some landers carry rovers to explore wider regions.