On what does the shape of an asteroid depend on?
Strength of its gravity
On what does the brightness of an asteroid depend on?
What is an asteroid?
"rubble piles" made out of metal and rock
Why is there no Planet between Mars and Jupiter, where the asteroid belt is?
Because of Jupiter's gravitational petrurbations, which prevented coalescence of material into a planet.
What is an orbital resonance?
Occurs when two orbiting bodies exert a regular, periodic graviational influence on each other (usually because their orbital periods ae related by a ratio of two small integers.)
What are Comets?
= small, primitive objects that contain a substantial quantity of water ice and other frozen volatiles.
Why do Comets have clouds of gas and dust, visible as long tails?
Because of the vaporiation of ice by increasing solar radiation.
What are the features of a comet?