Our Universe
A word used to describe space and all the energy and matter in it.
What is the universe?
What is a large celestial body that is composed of gas and emits light?
What is a star?
What are the approximate percentages of the two gases that make up stars?
What is 71% hydrogen and 27% hydrogen?
Two stars that orbit around their common center of mass.
What is a binary star system.
What does the H-R Diagram use to classify stars and which axis are they on?
What is Surface temperature (x-axis) and
Luminosity (brightness/absolute magnitude) y-axis
The middle of the Sun where energy is produced.
What is the core?
The order of our universe from big to small
What is universe, galaxies, stars, planets
Name three characteristics used to classify stars.
What is color, temperature, size, composition, and brightness.
This determines the color of a star.
What is temperature?
The class of very small stars with low luminosity and low/medium temperatures.
What are white dwarfs?
The outer atmosphere of the Sun.
What is the corona?
A collection of large and small bodies that orbit our central star, the sun.
What is the solar system?
Why is a term scientists use to describe the actual brightness of a star?
What is luminosity?
The order of stars from coolest to hottest.
What is it red, red-orange, yellow, white, blue.
90 % of the stars and our Sun are classified as what?
What are Main Sequence stars?
The visible surface of the Sun
What is the Photosphere?
A large collection of stars, gas, and dust and there are estimated to be 100 billion of these in the universe
What is a galaxy?
Compare and contrast absolute and apparent brightness.
What is apparent brightness is how bright the star is from Earth. Absolute brightness is the brightness of a star if it were at a standard distance from Earth.
The process that produces energy within the core of the star.
What is nuclear fusion?
What is the name of our galaxy and what type of galaxy is it?
What is the Milky Way and spiral (barred spiral)?
Temperature of stars are measured in what metric units?
What are Kelvins? (K)
What causes convection in the convection zone?
What is density?
How are distances measured in space and what is used to determine them?
What is a light year and what is the speed of light?
What are the four classes of stars based on size from biggest to smallest?
What are giants/supergiants, medium stars, white dwarfs, neutron stars.
What is the name of the model that astronomers use to describe the Sun as the center of our Solar System.
What is the heliocentric model?
What are the two things that appear backwards on the H-R Diagram.?
What is temperature -x-axis (goes from right to left/ cooler are red and blue are on hotter) and luminosity - negative numbers are brighter and + numbers are medium or dimmer.
What describes the how the different parts of the Sun have different periods of rotation?
What is differential rotation?