6.5 Flashcards
(20 cards)
What is the name of the galaxy where we live?
Milky Way
Which shapes best illustrate the galaxy where we live?
spiral
What is the closest star to Earth in our galaxy?
The closest star to Earth in our galaxy is the Sun
How many stars are in our galaxy?
There are more than 1,000,000 stars in our galaxy.
Is there a small quantity of dust between the stars in our galaxy?
False
Is there a small quantity of gas between the stars in our galaxy?
False
What word describes all of space and everything in it?
Universe
Why can we see other galaxies in space?
Because they contain stars that give out their own light.
What are the three shapes of galaxies?
Spiral, Elliptical, Irregular
What do scientists not know about galaxies?
Scientists do not know exactly how many galaxies there are in total.
What type of object is present in all galaxies?
One type of object in all galaxies is stellar dust.
List three other types of objects that must be present in all galaxies.
Stars, solar systems held together by gravity, and stellar dust.
How can clouds of stellar dust produce strong forces of gravity in galaxies?
Small forces that will become strong forces.
What is the most common type of object that gives out its own light in a galaxy?
Star.
What is a black hole?
A black hole is not actually a hole, but is a solid object.
Why do black holes appear black?
- They don’t reflect light.
- They absorb light.
What has been discovered about galaxies in space?
Most of the galaxies in space are moving further apart from each other.
How will the movement of galaxies affect their visibility from Earth in the future?
- Fewer will be seen.
- They will appear smaller.
How can you estimate the number of grains of sand on a beach?
Count the number of grains in a small volume and use the formula length x width x depth (make them the same unit).
How is estimating the number of grains of sand an analogy for estimating the number of galaxies?
Both methods are the same formula.
