Download A Star is a ball of matter that is pulled together by gravity, and that

Star Notes
Name:___________________
A Star is a ball of matter that is pulled together by ________________, and that gives of ________________
as a result of________________________________ (when two atoms bond together to make one heavier
atom).
1. Composition of Stars: The 2 most abundant elements in stars are ______________and ______________.
–Scientists determine the composition by studying the _________________that comes from a star.
How Light shows composition: when elements in a star burn, they give off certain colors of light. The
____________of _____________ corresponds to a specific _____________________of the light.
•Scientists look at the light from a star through a__________________________.
A spectroscope breaks
light apart and shows the wavelengths of the light.
•Each ____________________gives off a unique pattern, or color__________________. If scientists find
that pattern in a star’s light, they know that element is present in the star.
–Example: When you burn sodium, it produces a yellow flame.
•Astronomers match up the lines on the spectrum coming from a star with the dark lines different elements
produce when they burn to determine the _____________________________ of the star.
2. Temperature: Scientists estimate the _________________of stars by the _______________of the star.
3. Magnitude: The Brightness of a star depends on three things:
–__________________
–__________________
–__________________from us
•_____________________Magnitude:
How bright a star is when viewed from___________. A very large,
hot star could look dim just because it is so far away.
•_____________________Magnitude: the amount of ____________ that is actually given off by a star.
4. Measuring the Distance to Stars: we measure the distance between objects in space using ___________.
–Parallax is the apparent change in _______________of a star in the sky when viewed from two different
positions in earth’s revolution. The ______________a star is, the ________________its parallax, or
apparent movement. The _____________away a star is, the _______________its parallax.
•When we observe Star X from Location 1, it appears to be beside Star B.
•When we observe Star X from Location 2, it appears to be beside Star A. Did Star X really move? ______
5. Measuring Distance in Space
•Light-Year- The _____________that light can travel in one__________. 5,865,696,000,000 miles
•Astronomical Unit (AU)- the distance between the _________and the ___________(93 million miles)
6. ______________________are patterns of _________________in the sky.
•________________Constellations: Constellations that appear to _____________around the North Star.
•Major constellations: ____________________ and _____________________________
7. Important Stars
•_______________: The North Star: The star directly above the earth’s axis of rotation, or the north pole.
It appears to stay in the same place all year, and other constellations revolve around it.
•_________________________: Closest star to us (other than the__________)