Small Bodies Orbiting the Sun Review

Why do astronomers believe chondrite meteorites are about 4.6 billion years old—formed when the Solar system formed?

• Their chemical composition suggests they are pieces broken off Mars, which is believed to have formed at that time.

• There is no other reasonable period in the solar system's history when any meteoroids could have formed.

• The chemicals they are made of were only common at the formation of the solar system.

• Radioactive dating can be used to determine their age.

Fragments that do not completely burn in the atmosphere and eventually fall on Earth are called

• meteoroids.

• meteorites.

• meteors.

• asteroids.

What is a meteor?

• a glowing trail of hot gas and debris heated as an object moves through the atmosphere

• a space rock that survives its fall through Earth's atmosphere and reaches the ground

• the object that causes a "shooting star," but before it passes through the atmosphere

• any one of the large rocky bodies that orbit the Sun, primarily between Jupiter and Saturn

What is a meteoroid?

• a glowing trail of hot gas and debris heated by friction as an object moves through the atmosphere

• a space rock that survives its fall through Earth's atmosphere and reaches the ground

• the object that causes a "shooting star," but before it passes through the atmosphere

• any one of the large rocky bodies that orbit the Sun, primarily between Jupiter and Saturn

What is a meteorite?

• a glowing trail of hot gas and debris heated by friction as an object moves through the atmosphere

• a space rock that survives its fall through Earth's atmosphere and reaches the ground

• the object that causes a "shooting star," but before it passes through the atmosphere

• any one of the large, rocky bodies that orbit the Sun, primarily between Jupiter and Saturn

What is the difference between a meteor and a meteorite?

• A meteor is the flash of light in the sky. A meteorite is the solid body ending up on the ground.

• A meteorite comes from a comet. A meteor comes from an asteroid.

What are the three broad categories of meteorites?

• small, medium and large

• organic, inorganic, vegetal

• iron, stony, stony-iron

• red, yellow and blue

All of the Asteroids in the Asteroid Belt together have

• a tiny fraction of Earth's mass.

• about Earth's mass.

• about ten times Earth's mass.

• a mass somewhere between the mass of Mars and the mass of Jupiter.

Infrared observations are used to determine the mass of asteroids because ____.

• asteroids reflect too little visible light to use optical telescopes for the measurements

• the infrared radiation is the glow of heat from the asteroid, and larger asteroids emit more infrared light

• the Hubble Space Telescope only has infrared cameras

• most asteroids are made of dark minerals which are more efficient at reflecting infrared light than visible light

Asteroids are _______.

• small bodies, typically the size of a grain of sand or a boulder

• can range in size from a few meters to many hundreds of kilometers

• are larger objects, a few hundred kilometers in size, but not quite large enough to be classified as a planet

• are about the same size as planets, but have not pulled themselves into a spherical shape