Asteroids Lecture Notes

Flashcards about asteroids, focusing on definition, types, and locations.

Asteroid

Relatively small, rocky or metallic object that orbits a star.

Asteroid Detection

Photograph the sky for extended period. Asteroid motion shows as streak across the stars.

Main Belt Asteroids

Asteroids that orbit between the orbital paths of Mars (1.5 au) and Jupiter (5.2 au).

Asteroid Belt

Disk-shaped region between the orbital paths of Mars and Jupiter where most asteroids orbit.

Trojan Asteroids

Two groups of asteroids that travel with Jupiter, one leading and one following in orbit.

Earth-Crossing Asteroids (ECAs)

Asteroids whose paths cross Earth’s orbit, posing a collision risk.

Near-Earth Object (NEO)

An asteroid, comet, or large meteoroid whose orbit intersects Earth’s orbit.

Meteoroid

A rock orbiting the Sun, ranging from a grain of sand to larger than a boulder.

Vesta

Second most massive asteroid in the asteroid belt and sometimes referred to as a protoplanet, visited by Dawn spacecraft.

C-type Asteroids (Carbonaceous)

Asteroids primarily made of carbon and silicate rocks, are primitive, most common, and found in outer asteroid belt.

S-type Asteroids (Siliceous)

Asteroids made of silicate (stony) material, greenish to reddish, chemically like volcanic rocks, located in inner asteroid belt.

M-type Asteroids (Metallic)

Asteroids composed of mostly nickel and iron, rarest type, reddish, found in the middle region of the asteroid belt.