astrology and cosmology

Front

How does redshift lead to idea of expanding universe

Back

1.) redshift is the increase in observed wavelength

2.) radiation of distant galaxies observed to be redshifted

3.) redshift provides evidence that galaxies are moving apart

4.) galaxies moving apart means universe must be expanding

Front

how can standard candles be used to determine the distance of galaxies

Back

1.) standard candles have known luminosity

2.) radiant flux intensity can be measured by the observer
3.) distance can be found using the formula

Front

why does redshift occur

Back

1.) galaxies are moving away from observer

2.) this causes the observed wavelength to be increased by dopplers effect

Front

how the surface temperature of distant star can be determined from wavelength spectrum

Back

1.) by wavelength of peak intensity

2.) temperature can be determines using Wiens displacement law

Front

explain how hubbles leads to idea of Big bang universe

Back

1.) all parts of the universe are moving away from each other

2.) more distant objects moves further away

3.) in the apart, matter must have been really close

Front

how did cosmologists realize light from distant stars undergoe redshift

Back

1.) examining the lines of the spectrum of light of that star

2.) comparing it with already known spectrum