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Stars
Galaxies
Universe
Solar System
Universe Beyond
100
Describe a constellation.
A constellation is a pattern of stars in the sky.
100
This is a star's brightness as seen from Earth.
Apparent brightness is a star's brightness as seen from Earth.
100
This is star's brightness as seen from Earth.
apparent brightness
100
How is a star born?
A star is born when nuclear fusion begins inside a protostar.
100
How many stars are main sequence stars?
More than 90% of stars are main sequence stars.
200
Describe a pulsar.
A pulsar is a neutron star that appears to produce pulses of radio waves.
200
Describe a nebula.
A nebula is a large cloud of gas and dust in a galaxy.
200
This is a star's brightness the star would have if it were a standard distance from Earth.
absolute brightness.
200
Describe a binary star.
A binary star is a star system containing two stars.
200
Describe constellations.
Constellations are imaginary patterns of stars.
300
Describe a protostar.
A protostar is the earliest stage of a star's life.
300
Describe The Milky Way.
Our solar system is located in The Milky Way Galaxy. It is a spiral galaxy.
300
Describe parallax.
Parallax is the apparent change in position of an object when you look at it from different places.
300
Describe a pulsar.
A pulsar is a neutron star that appears to produce pulses of radio waves.
300
How long do astronomers believe the universe will expand?
Astronomers believe the universe will expand forever.
400
How do astronomers use the Hertzsprung-Russell diagram?
Astronomers use the H-R Diagram to graph stars' absolute brightness and temperature.
400
Describe the four types of galaxies.
Spiral Galaxy - have a bulge in the middle and arms that spiral outward, like pinwheels. Quasar - looks almost like stars, are very bright and very far away Ellipital Galaxies - look like round or flattened balls Irregular Galaxies - have no regular shape, contain bright, young stars
400
Describe a wavelength.
A wavelength is the distance between the crest of one wave of electromagnetic radiation and the crest of the next one.
400
Why do astronomers use light years?
A light year is used because distance between objects is so large.
400
Describe dark matter.
Dark matter can't be seen directly. It is matter that does not give off electromagnetic radiation.
500
How long does a star live?
A star's life depends on its mass.
500
Describe an eclipsing binary.
An eclipsing binary is a star system in which one star blocks the light from another star.
500
Why do astronomers use parallax?
Parallax is the apparent change in position of an object when you look at it from different places. Astronomers use parallax to measure distances to nearby stars.
500
How does a star's color reveal its temperature?
The coolest stars are red and the brightest stars are bluish in color.
500
How old is our solar system?
Our solar system is about five billion years old.