Asteroids Flashcards
What are asteroids?
Asteroids are rocky and irregularly shaped celestial objects formed over 4.6 billion years ago from the remnants of the formation of the solar system.
What determines the composition of an asteroid?
The composition of an asteroid depends on its distance from the Sun. Asteroids closer to the Sun have less silicates, while those farther away tend to contain silicates.
What is the composition of metallic asteroids?
Metallic asteroids are generally composed of 80% iron and 20% mixture of nickel, iridium, gold, and magnesium.
How many asteroids were identified in the solar system as of 2019?
According to NASA, there were 930,664 identified asteroids in the solar system as of 2019.
What are the two main ways to classify asteroids?
Asteroids can be classified according to their composition or location in the solar system.
What are the types of asteroids based on composition?
• C-type (chondrite): Made of clay and silicates.
• S-type (stony): Made of nickel, iron, and other silicates.
• M-type: Composed of pure nickel and iron.
What are the types of asteroids based on location?
• Main Belt: Located between the orbits of Mars and Jupiter.
• Near-Earth asteroids: Asteroids that pass near Earth.
• Trojans: Asteroids located near Jupiter’s Lagrange points.
What is the largest known asteroid in the inner solar system?
The largest known asteroid is 4 Vesta, with an average diameter of 55 km.
Who discovered 4 Vesta and when?
4 Vesta was discovered by Heinrich Wilhelm Olbers in 1807 in Bremen, Germany.
Who discovered Ceres, the largest asteroid in the inner solar system, and when?
Ceres was discovered by Giuseppe Piazzi in 1801. He initially thought it was a comet but later identified it as a planetoid.
