Astronomy: Comets and Asteroids

These flashcards cover key concepts from the lecture on comets and asteroids, including notable comets, characteristics of asteroids, and significant astronomical phenomena.

What is Comet Hale-Bopp known for?

Comet Hale-Bopp was one of the most attractive and easily visible comets of the twentieth century.

What are the two types of tails that comets have?

Comets have a long blue ion tail and a shorter white dust tail.

What are asteroids primarily composed of?

Asteroids have different compositions, primarily categorized as S-type, C-type, and M-type.

What did the NASA Dawn spacecraft reveal about Vesta and Ceres?

Vesta is irregularly shaped with a mountain twice the height of Mt. Everest, while Ceres is a dwarf planet and more round.

How are the moons of Mars, Phobos and Deimos, believed to have formed?

They may be captured asteroids based on their similar surface materials to those in the asteroid belt.

What phenomenon was observed during the impact of Comet Shoemaker-Levy 9 with Jupiter?

It created a visible impact dust cloud and several bright spots on Jupiter.

What structure does a comet consist of?

A comet typically consists of a nucleus, a coma, and two tails.

What does the orientation of a comet's tail indicate?

The tail direction changes based on the comet's position relative to the Sun, being behind the comet before perihelion and ahead after.

Describe the surface characteristics of asteroid Itokawa.

Itokawa appears to have no craters and consists of rocks and ice chunks, suggesting a loosely-bound rubble pile.

What was the significance of the discovery of the Kuiper Belt?

It suggested there is a reservoir of frozen chunks that can be potential comet nuclei at the edge of the Sun's gravitational influence.