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Astronomy
Question | Answer |
---|---|
Big Bang | the event from which the universe began expanding |
what is the universe doing | expanding |
hubbles law | galaxies are moving away from us the father the faster they go |
what does blue shift look like | more tightly compacted rays |
what does red shift look like | looser less compacted rays |
object approaching | short blue rays |
object receding | long red waves |
cosmic background radiation(microwaves) | background radiation from the big bang consists of photons(cmb) |
what do stars differ from | mass, size, temperature, color, luminosity |
the more massive a star is | the greater the gravity and the hotter and denser a star must be |
what size star is our star from the range of small medium and large | our sun is a medium size star |
what do stars consist of | controlled atomic reactions called nuclear fission |
nuclear fission | in which hydrogen (nuclei) atoms fuse to form helium (nuclei) atoms |
what happens during each step of the process of nuclear fission | mass is lost and energy is released |
the energy released from the star causes what | to shine and it gives it its high temperature |
star stability | energy from fusion stabilizes the star by producing pressure needed to counteract the force of gravity |
fusion > gravity =? | expansion |
fusion< gravity =? | contraction |
fusion=gravity is ? | stable |
stable stars are plotted on a what | hr diagram |
is the sun contracting or expanding | the sun is slowly getting bigger and brighter |
what color is associated with the hottest star temperature | BLUE stars |
what color is associated with the coolest star temperature | RED stars |
what color is our sun | our sun is a yellow star with a surface temperature of about 5,500⁰ c |
what are the spectral class letters | (O)h (B)oy (A) (F)ailing (G)rade (K)ills (M)e (obafgkm) |
what are the list of stars colors from coolest to hottest | red , orange, yellow, yellow-white, white, blue-white , blue |
what are the two kinds of brightness | apparent brightness, luminosity |
apparent brightness | how bring the object APPEARS TO US on earth |
luminosity | how bright a star actually is |
where do stars form | in the nebulae (a large cloud of gas and dust) due to gravity are called dense cores and form new stars |
how do stars emit energy | by nuclear fission |
what is the longest phase in a stars life | main sequence stage(hydrogen converts to helium) |
when does the star enter into the next stage of life | after all the hydrogen has fused into helium |
what happens after all the hydrogen is gone | star ejects matter and rapidly loses mass until only the core remains |
what does the final stages of a stars life depend on | the mass of the star |
what is the stages of life for a low mass star | Nebula --> Main sequence star --> Red giant -->Planetary nebula --> White dwarf |
for a low mass star what comes after the main sequence star stage | red giant |
for a low mass star what comes after the red giant stage | planetary nebula |
for a low mass star what comes after the planetary nebula stage | white dwarf |
what is supernova | is a gigantic explosion in which a high- mass star throws its outer layer into space but the core remains |
what is the stages of life for a high mass star | Nebula --> Main sequence star --> Red super giant --> Supernova --> Neutron star -->Black hole |
for a high mass star what comes after the supernova stage | either neutron star or black hole |
what does a h-r diagram plot stars according by | luminosity and temperature |
upper left stars on a h-r diagram are? | large, hot, luminous |
what is an example of an upper left star on a hr diagram | blue giant |
lower right stars on a hr diagrams are | small,cool,dim |
what is an example of an lower right star | red dwarf |
what stage of life is our sun in | the main sequence |
where are main sequence stars on a hr diagram | in the top left(hot and bright) to bottom right (cool and dim) |
the larger the amount of mass in as star | the more luminous it is |
what is a comet | a mass made up of frozen ice and rock |
what forms the cloud called the coma around the comet | vaporized gases and released dust |
what are meteoroids | small pieces of rock moving through space |
a meteoroid that burns up into the earths atmosphere is called what | a meteor |
when a meteoroid strikes earth it is called a what if it gets through earths atmosphere | a meteorite |
asteroid | a piece of rock similar to the materials that formed into planets |
where are most asteroids found | in the asteroid belt in between mars and Jupiter |
kuiper belt | like the asteroid belt but father out and made up of icy objects |
who was the first country in space | the soviet union |
what does nasa stand for | National Aeronautics and Space Agency |
when was nasa founded | 1958 |
what was the space race | the race for countries to be the first on the moon |