Comets and Asteroids Flashcards
What are comets?
Remnants left over from formation of solar system
Where do comets lie?
In the Oort cloud around 50000AU and the Kuiper belt
Size of comets
Range from a few miles to tens of miles
How do comets start trip to Earth?
Gravitational perturbation causes orbit change so they pass through inner solar system
What happens to the comets orbit if its hyperbolic?
Enters solar system once before leaving again
What happens to the comets orbit if its ellipitcal?
enters elliptical orbit and remains trapped
Comet Halley orbit period
76 years
What are comets like with elliptical orbit?
Tails that points away from sun with ion and dust tails
What do comets consist of?
Rocky core surrounded by ice.
Added blend of frozen gases
Impact of life on earth
Dangerous due to impact but also can enrich Earth
What was comet shoemaker-Levy 9?
Comet collided with Jupiter in 1994 after orbiting it.
Why was it a more dramatic collison?
Prior fragmentation of the comet before this impact
How big was fragment-G?
Mile-wide
How hot did it reach?
20,000 K
Results of the impact with Jupiter
Debris plume 3000km up.
Raining molten debris
What are asteroids?
rocky objects orbiting the sun.
What are the three types of asteroids?
Carbenaceous chondrite
Silicaceuous
Metallic
How are asteroids classified?
How much iron they contain
Properties of carbonaceous chondrites
75% of all known asteroids,
Stony, non- metallica
253 Mathilde
Properties of silicaceous
17% of known asteroids
Metallic nickel-iron mix with mg and iron silicates
433 Eros
Properties of Metallica
8% of known asteroids
Bright, pure nickel-iron material
216 Kleopatra
Age of lunar crater
3.5 billion years ago
Ceres asteroid
Diameter of 975km
Has 30% of asteroidal mass
Why can asteroids not be remains of a destroyed planet?
Total mass of all of them is less than 1/1000 of Earths
