Sentences with phrase «observed apparent brightness»

By comparing this new diagram to the Hertzsprung - Russell diagram for the nearby stars, you will see that the ratio of the observed apparent brightness to the absolute brightness is the same for every kind of star - and this ratio gives you then the distance to the cluster.

One technique for measuring the expansion rate is to observe the apparent brightness of objects of known luminosity like Type Ia supernovas.

Not exact matches

Its actual brightness, which we can observe on earth, is called the apparent brightness.

Because all the stars in the Small Magellanic Cloud have approximately the same distance to us, the observed relationship between apparent brightness and period implies that there is an equivalent relationship between absolute brightness and oscillation period.

In 1996, another group of astronomers using the Hubble Space Telescope discovered that they might have directly observed a companion to Proxima with the implied brightness of a brown dwarf and an apparent visual separation of only about half the Earth - Sun distance — 0.5 AU (Schultz et al, 1998).