physics 8.4

stars moving away from us have ___ spectra because their wavelengths are ___

redshifted, longer

stars moving towards us have

blueshifted spectra

the more dramatic the shift →

the faster the star is moving

parallax (nearest objects)

measures movement relative to earths orbit. The more the object moves over the year the closer it is.

standard candles (moderately distant objects)

using objects of known brightness to find distance based on how bright they are. The dimmer it is the farther it is from earth.

hubble’s law (farthest objects)

calculated galaxies velocities by redshift and discovered everything in the universe is moving away from us.

relationship between distance and velocity based on hubbles law

linear, farther galaxies are moving away faster

hubbles constant graph represents

the rate at which the universe is expanding