Chapter 22: Astronomy Flashcards
What is a solar system?
Collection of planets and moons that orbit a star or stars
What is a galaxy?
Millions of solar systems
What is a universe?
Millions of galaxies
What does the moon orbit?
The moon orbits the Earth. Other planets also have their own moons.
What is gravitational field strength and does it change?
Gravitational field strength is how strongly something pulls an object towards it. It is different on different planets and moons, because they have different masses. Larger mass = larger g.
What does gravitational force do?
If an object is sighing the field of another object’s gravitational force, then it will travel around it in a path known as an orbit.
What is the relationship between orbital speed, orbital radius and time period?
Orbital speed = (2 x Pi x orbital radius) / time period
How does the orbit of a comet differ from that of a planet?
Comets have elliptical orbits, which means they have two focal points that they orbit.
