Astrophysics Flashcards
Define the universe
A collection of billions of galaxies
Define a galaxy
A large collection of billions of stars
Define a solar system
A collection of planets orbiting a common star
Which galaxy is our solar system in?
The milky way
Which unit is gravitational field strength measured in?
N/kg, Newtons per kilogram
Describe the orbital speed and shape of the orbit of moons
A near constant orbital speed and slightly elliptical orbit
Describe the orbital speed and shape of the orbit of planets
A near constant orbital speed and a slightly elliptical orbit
For comets, describe their orbital speed, shape of orbit, and what they orbit
Near constant orbital speed, highly elliptical orbit, orbiting the Sun
What do artificial satellites orbit?
The Earth
Why does a comet’s speed change
When a comet gets closer to a star, it’s speed increases because the ice inside it melts therefore it’s mass decreases
Describe the first stage of a star forming
A nebula of dust and gas begins slowly clumping together due to gravity. They continue to clump together until pressure and temperature is great enough for nuclear fusion to occur
Which directions of movement cause red shift and blue shift?
Red shift is caused by objects moving away from the observer
Blue shift is caused by objects moving towards the observer
