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Science Ch. 19
Question | Answer |
---|---|
The color of a start depends on its | temperature |
What color are the hottest stars? | blue |
The H-R diagram shows the relationship of a star's surface temperature | absolute magnitude |
What objects are formed from the materials in the core of a supernova? | black holes and neutron stars |
What is the term for the actual brightness of a star? | absolute magnitude |
What is the term for the brightness of a star as it appears to an observer on Earth? | apparent magnitude |
What is the term for a gigantic explosion that causes the death of a large star | supernova |
What is a the term fora massive and dense object from which even light cannot escape its gravity? | black hole |
What type of star is bright and hot? | blue star |
What type of star is bright and cool? | red giant |
What type of star is dim and hot? | white dwarf |
What type of star is dim and cool? | red dwarf |
Name the three major types of galaxies? | Spiral galaxy, irregular galaxy, and elliptical galaxy |
Why do scientists study distant galaxies? | To learn what early galaxies looked like |
Is the universe expanding outward or inward? | Outward |
What is the term for radiation left over from the big bang that fills all of space? | cosmic background radiation |
What is the term for the type of galaxy that has a center bulge and outer "arms"? | spiral galaxy |
What is the term for the type of galaxy with a bright center and little to no dust and gas? | elliptical galaxy |
What is the term for the theory that states the universe began with a huge explosion? | Big Bang Theory |
What is the term for a large cloud of dust and gas where new stars are formed or stars explode? | nebula |
What is the term for the study of the origin, structure, and future of the universe? | cosmology |
Scientists think that the universe will do what? | Expand forever |
What does a star's color indicate? | It's temperature |
The H-R diagram shes the relationship between a star's surface temperature and what? | It's absolute magnitude |
What star is the hottest? | Main-sequence blue star |
According to the big bang theory, how old is the universe? | 13.7 billion years old |
What type of galaxy do the scientists think the milky way is? | spiral galaxy |
Which is a bigger: a nebula or a galaxy? | Galaxy |
What part of the modern H-R diagram do cool, bright red stars appear? | bottom right |
What is one way scientists use to calculate the age of the universe? | They measure the distance from Earth to various galaxies |
Why do black lines appear on an absorption spectrum? | Black lines appear where colors of light are absorbed by a star's atmosphere |
What do the pattern of lines in a star's absorption spectrum represent? | Some of the elements in the star's atmosphere |
Elliptical galaxies and the halos of spiral galaxies contain groups of stars called what? | globular clusters |
According to the big bang theory, what filled the universe after the original explosion? | cosmic background radiation |
The universe is organized according to what? | a loosely arranged structure |
What are the three major types of galaxies identified by Edwin Hubble? | spiral, elliptical, and irregular |
Why do scientists study distant galaxies to learn about early galaxies? | Because it takes a long time for light to travel through space, looking at distant galaxies shows what early galaxies looked like |
What type of star has used up all of its hydrogen and is the leftover center of an old star? | white dwarf |
Which is larger: a galaxy or a globular cluster | galaxy |
What do the patter of lines in a star's absorption spectrum represent? | Some of the elements in the star's atmosphere |
Elliptical galaxies and the halos of spiral galaxies contain groups of stars called | Globular clusters |