Busy. Please wait.

show password
Forgot Password?

Don't have an account?  Sign up 

Username is available taken
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.
We do not share your email address with others. It is only used to allow you to reset your password. For details read our Privacy Policy and Terms of Service.

Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.
Don't know
remaining cards
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

Ch. 21 Earth Science

7th Grade finals test

telescope A device that makes distant objects appear to be closer
electromagnetic radiation energy that can travel through space in the form of waves
wavelength distance between the crest of one wave and the crest of the next wave
spectrum a range of different colors of different wavelengths
optical telescope uses lenses or mirrors
refracting telescope uses convex lens
convex lens a piece of transparent, curved glass
reflecting telescope a curved mirror that collects light
radio telescopes curved lenses that reflect other waves and focus on radio
observatory a building that contains one or more telescopes
constellation an imaginary pattern "drawn" by the stars
spectrograph breaks light in to colors and and produces images of it
apparent brightness brightness seen on earth
absolute brightness the brightness the star would have if it were at a standard disatnce from Earth
light year distance that light travels in one year
parallax apparent change in position of an object when looking at it from a different place
main sequence surface temperature increases, and is the main life of a star
binary star a two star system
eclipsing binary a binary system in which the dim star eclipses the bright star
open cluster a much less dense cluster of stars
globular cluster a much more dense cluster of stars with millions of them
galaxy a group of stars, dust, and ice held together by gravity
quasar active young galaxies with giant black holes
universe all of space and everything in it
Created by: WhiteWyvern95