Busy. Please wait.

Forgot Password?

Don't have an account?  Sign up 

show password


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.

By signing up, I agree to StudyStack's Terms of Service and Privacy Policy.

Already a StudyStack user? Log In

Reset Password
Enter the email address associated with your account, and we'll email you a link to reset your password.

Remove ads
Don't know (0)
Know (0)
remaining cards (0)
To flip the current card, click it or press the Spacebar key.  To move the current card to one of the three colored boxes, click on the box.  You may also press the UP ARROW key to move the card to the "Know" box, the DOWN ARROW key to move the card to the "Don't know" box, or the RIGHT ARROW key to move the card to the Remaining box.  You may also click on the card displayed in any of the three boxes to bring that card back to the center.

Pass complete!

"Know" box contains:
Time elapsed:
restart all cards

Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how

Unity's Astronomy

Astronomy for Ms. Hall

Who were three of the first early astronomers? Ptolemy, Copernicus, Tycho Brahe
What is a "Light Year"? A unit of length equal to the distance that light travels in one year
What makes up the first stages of a star? Gas and dust
What is it called when when gravity pulls gas and dust together? A nebula
What does Nuclear Fusion combine? Hydrogen atoms
How does a Red Giant "die"? It burns out like a candle
What are two things that may happen to a star that explodes? Turning into a Super Nova or a Black Hole
What does "H-R" Stand for in H-R Diagram? Hertsprung-Russell
What is an H-R Diagram? A graph that shows the relationship between a star's surface temperature and absolute magnitude
What is the Main Sequence? The diagonal pattern on an H-R diagram where most stars lie
What is a Black Hole? An object that is so massive that even light cannot escap its gravity
What is a Galaxy? A collection of stars, dust and gas held together by gravity
What is an example of a spiral galaxy we are familiar with? The Milky Way
What is a massive blob of stars? Elliptical Galaxies
Do irregular galaxies fit into any certain class? No
How long did the Big Bang Theory occur? 13.7 Billion years ago
What makes up comets? Ice, rock, and cosmic dust that is loosely packed together
Are comet tails a solid? No
What makes a comet tail? The melting of the ice in a comet that gives off gas
Do comet tails point towards the sun or away from the sun? Away
Created by: hcps-bowlingue