unit review-Objects In Space Flashcards
what’s is the big bang theory? when did it occur? what evidence is there to support it?
states that 14 billion years ago, everything in the universe existed as an fixed mass that was hot and dense. the mass suddenly expanded and formed galaxies a billion years ago
what is a elliptical shaped galaxy?
an elliptical galaxy has an approximately ellipsoidal shape and smooth, nearly featureless image.
what is a spiral shaped galaxy?
a flat rotating disk with stars, gas, and dust
what is a lenticular shaped galaxy?
disk galaxies used most of latter and now little on going star formation
what is a irregular shaped galaxy?
a galaxy that does not have a regular shape
what shape of galaxy is the milky way?
a spiral
what is an asteroid? what is it made of? where are there 2 asteroid belts in our solar system?
small celestial object made of mostly rock and metal. most are located in the asteroid belt between mars and jupiter
what is a comet? what is it made of? how is it’s tail formed?
a comet is a large chunk of ice, dust, and rock that orbits the sun. when it gets closer to the sun it creates a glowing sphere with a tail
what is a meteoroid?
a small particle from an asteroid or comet orbiting the sun
what is a meteor?
a meteoroid that is observed as it burns up in earths atmosphere
what is a meteorite?
a meterorite that survives
