ASTRONOMY Flashcards
lUMINOSITY
total power emitted from a star
radiant flux intensity
amount of power polairisng normally per unit surface area
luminiuos flux
ntensity of radiation at a distance from the star
standard candles
an astronomical object which has a known luminious
Weins displacement law
the black body radiation curve for different temperatures peak at wavelengths inversely proportional to the temp.
black body
idealised physical body that absorbs all EMR regardless of frequency or angle of incidence
Stefan boltzman law
total power emitted by a black body per unit area per second is proportional to the 4th power of the absolute temp of a body
Hubble’s law
recessional speed of galaxies moving away from the earth is proportional to their distance from the earth
Doppler red shift effect
fractional increase in wavelength as the source moves away from the observer
light year
it is the distance travelled by a light in a vacuum in a time of one year
light year
it is the distance travelled by a light in a vacuum in a time of one year
