What is "apparent brightness"

Usage examples of "apparent brightness".

When Arp complied with that condition, he was then challenged for his prediction as to how the counts of quasars should vary as a function of their apparent brightness.

Calhoun drilled him in the use of brightness-charts, by which the changes in apparent brightness of stars between overdrive hops could be correlated with angular changes to give a three-dimensional picture of the nearer heavens.

Galaxies increase in numbers as they decrease in apparent brightness, and it is natural to assume that these two go together: if we double the distance of a galaxy, it appears one-quarter as bright, but we expect to see four times as many like it if space is uniformly filled with galaxies.

He made the acting pilot look up the intrinsic brightness of its sun and measure its apparent brightness from just off Dara.

Now, the apparent brightness of a star depends on two factors: how much light it radiates (its luminosity), and how far it is from us.

For nearby stars, we can measure their apparent brightness and their distance, and so we can work out their luminosity.

Conversely, if we knew the luminosity of stars in other galaxies, we could work out their distance by measuring their apparent brightness.

There was a catalog of several hundred stars, including the latitude, longitude, and apparent brightness of each one, written in such a tiny hand that it was almost impossible to read.

From this he deducted that the spindizzy screen, though itself invisible, cut down the apparent brightness of the stars by about three magnitudes, as had the atmosphere of the Earth in the region where Chris hj~d lived.

The candles sat on the floor in front of the Mirror in a triangular configuration, and despite their apparent brightness, gave off only a faint illumination.

It shows up as a slight bend in a graph of how a distant supernova's apparent brightness varies with its red shift.