Studied by 13 peoplebig bang theory
the universe began expanding from a point 13.7 Billion years ago
13.7 billion years
how long ago did the universe start expanding?
galaxy expansion/redshift
evidence 1 for the big bang theory
cosmic microwave background (CMB)
evidence 2 for the big bang theory
cmb
leftover heat from the “big bang” (peak intensity - microwave)
2.7 K
temperature of space due to cmb
lightyear (ly)
distance light would travel in a year in a vacuum
parsec (pc)
the distance of one arc second of parallax
parallax
the apparent motion of an object due to the motion of the observer
astronomical unit (AU)
the average distance from Earth to the sun
MVEMABJSUNKBOC
the order of the solar system
mercury Venus Earth mars
terrestrial
terrestrial
mercury Venus Earth mars are __________
jupiter saturn Uranus neptune
jovian
jovian
jupiter saturn Uranus neptune are __________
asteroid belt
between Mars and Jupiter
Kuiper belt
after neptune
ort cloud
after Kuiper belt
comet
has a highly elliptical orbit
nebula protostar main sequence red giant planetary nebula white dwarf black dwarf
life cycle for a star less than 8 SM (7 steps)
nebula protostar main sequence red giant red supergiant supernova neutron star
life cycle for a star greater than 8 SM (8-20 SM)
nebula protostar main sequence red giant red supergiant supernova black hole
life cycle for a star greater than 8 SM (20-80 SM)
nebula protostar main sequence red giant red supergiant supernova supermassive black hole
life cycle for a star greater than 8 SM (80+ SM)
1) nebula
collection of gas and dust
2) protostar
spherical, but no fusion
3) main sequence
all fusing H (hydrogen) (our star)
4) red giant
fusing non-H elements up to Fe
5) planetary nebula
after red giant, if less than 8 SM
6) white dwarf
after planetary nebula (less than 8 SM)
7) black dwarf
after white dwarf (not yet observed) (less than 8 SM)
5) red supergiant
after red giant (greater than 8 SM)
6) supernova
after red supergiant (greater than 8 SM)
7) neutron star
after supernova (8-20 SM)
7) black hole
after supernova (20-80 SM)
7) supermassive black hole
after supernova (80+ SM)
radar
shoot light, see how long it takes to bounce back (solar system)
parallax
two known distances, two different points of the year, find the angle
spectroscopic parallax
looking at two stars where the wavelength has shifted, redshift of stars
cepheid variable
solve for distance - b = L/4pir²
type 1a supernovae
occurs at a known luminosity, use equation to solve for distance
Hubble’s constant
redshift of galaxies (H0)
planet
a celestial body that orbits a star
single star
a luminous sphere of plasma held together by its own gravityb
binary star
two stars orbiting a common center
planetary system
gravitationally bounded non-stellar objects in orbit around a star or star system
constellation
a pattern of stars visible from Earth that are not gravitationally bounded
stellar clusters
a group of stars gravitationally bounded together
nebula
the ejected envelope of a red giant star
galaxy
stars, gas, and dust held together by gravitational forces
clusters of galaxies
two or more galaxies that are close enough to each other to affect each other through gravitation
Note
Flashcard