Chapter 14: Solar System Debris
Large meteoroids are thought to collide with Earth ...
a few times in every million-year period.
The major impact in the Yucatan wiped out the dinosaurs ...
about 65 million years ago.
The tail of a comet always points ...
away from the Sun and becomes longest and brightest at perihelion.
Which of the following objects would be found on the Moon's surface?
meteorites
Which of the following gives direct information about the age of the solar system?
meteorites from asteroidal debris
What part of a comet has only been seen by a space probe?
nucleus
Iron meteorites are believed to come from ...
the core of a dense M-type asteroid, now broken up.
The Oort Cloud is thought to be...
the spherical cloud of comets and some larger icy bodies surrounding the outer solar system.
Meteorites are valuable to astronomers because ...
they may provide evidence about the process in which the solar system was born.
About what percent of all asteroids are S-type asteroids?
15%
About what percent of all asteroids are C-type asteroids?
75%
What is the typical size of most known asteroids?
a few kilometers
The nucleus, or main solid body, of a comet has a typical size of...
a few kilometers.
The Perseid meteor shower gives us about a meteor every minute in mid ...
August
The type of asteroid that would appear darkest and reflect the least light is type...
C
The three largest asteroids are ...
Ceres, Pallas, and Vesta
What is so unusual about Pluto's orbit?
It is more inclined to the ecliptic than any of the eight planets.
Why do researchers believe that asteroids in the asteroid belt are primal rocks that did not merge into a planet?
Jupiter's gravity could have prevented these objects merging into a single body. The differences in chemical compositions of the asteroids are too large for them to have originated in a single body. The total mass of the asteroids in the asteroid belt is much smaller than that of any terrestrial planet in our solar system.
From its orbit, we now recognize Pluto as one of the largest members of the ...
Kuiper Belt.
The type of asteroid that would be the densest would be type ...
M
Long period comets are thought to reside mainly in the ...
Oort Cloud.
When a formal definition of a planet in the solar system was adopted, Pluto was reclassified as a dwarf planet. What characteristic of planets does NOT describe Pluto?
Planets have cleared the neighborhood around their orbit.
What is the defining property of the Trojan asteroids?
They have orbits at the distance of Jupiter and 60 degrees ahead of or behind it.
Pluto is most similar to ...
Triton
Meteor showers are the result of debris left behind by the passage of a decaying comet.
True
Most comets are discovered when their coma develops, giving them a fuzzy appearance instead of stellar such as asteroids.
True
What are comets made of?
dark colored complex hydrocarbons metallic dust particles silicates and rocky dust silicates and rocky dust
The first hint of the role of asteroids in extinction of the dinosaurs came from ...
finding a layer of worldwide iridium enriched dust.
The orbits of most comets ...
lie almost entirely beyond the orbit of Neptune.
The orbits of most asteroids ...
lie entirely beyond the orbit of Mars.