and he further infers that this luminosity is to a great extent independent of the nature of the vapor or gas, so that a gas which would burn without producing light at the pressure of the ...

The first key, the period-luminosity scale discovered by Henrietta ... was more than 900,000 light years from Earth -- way beyond our own galaxy -- a surprise to everyone at the time.

Luminosity is another standout feature of this ... including a couple of clerestory windows that flood the interior with natural light from all angles. Apart from making the living space bright ...

The brighter the star is overall, the longer the period of luminosity. Since the cepheids ... distances in space only worked within about 100 light years. With Leavitt's findings, distances ...