Chapter 27.1 Flashcards

Front 1

star

Back 1

body of gases that gives off a tremendous amount of radiant energy in the form of light and heat

Front 2

spectrometer

Back 2

a device that separates light into a different color, or wavelengths

Front 3

circumpolar

Back 3

describing any star that is always visible in the night sky and, from the Northern Hemisphere, can be seen circling Polaris.

Front 4

doppler effect

Back 4

apparent shift in the wavelength of energy, such as sound wave or light wave, emitted by a source moving away from or toward an observer

Front 5

blue shift

Back 5

the colors in the spectrum of a star moving toward earth

Front 6

red shift

Back 6

apparent lengthening of the light waves emitted by a star moving away from the earth

Front 7

light-years

Back 7

distance that light travels in one year, about 9.5 trillion km

Front 8

parallax

Back 8

method of determining the distance from the earth to a star based on the shift in the apparent position of the star when viewed from different angles

Front 9

Cepheid variable

Back 9

a star that brightens and fades in a regular pattern

Front 10

apparent magnitude

Back 10

brightness of a star as it appears from the earth

Front 11

absolute magnitude

Back 11

brightness of a star as it would appear if located 32.6 light-years from the earth

Front 12

H-R diagram

Back 12

Hertzsprung-Russell diagram' graph showing the relationship of the surface temperature and absolute magnitude of a star

Front 13

main-sequence stars

Back 13

star with characteristics that place it within a band running through the middle of the H-R diagram

Front 14

giants

Back 14

very large, cool, bright star

Front 15

super giants

Back 15

extremely large,, giant star

Front 16

white dwarfs

Back 16

small, hot, dim star