Astrophysics standard candle

For an object to serve as a standard candle
Astronomers must know its inherent brightness
Or luminosity.
They can compare that to how bright (or dim) the object appears in the sky to work out its distance.
In 1993
The astronomer Mark Phillips plotted how the luminosity of Type Ia supernovas changes over time.

A standard candle is an astronomical object that has a known absolute magnitude.
They are extremely important to astronomers since by measuring the apparent magnitude of the object we can determine its distance using the formula:

Several methods rely on a standard candle
Which is an astronomical object that has a known luminosity .
The ladder analogy arises because no single technique can measure distances at all ranges encountered in astronomy.

There are several types of 'standard candle' objects for which we can predict the luminosity from some other measurement.
Two of the most important are Cepheid variable stars and type 1A supernovae.
1) Cepheid variables Cepheid variables are a special type of star with a luminosity which varies on a regular cycle.

A standard candle is an astronomical object that has a known absolute magnitude

They are extremely important to astronomers since by measuring the apparent magnitude of the object we can determine its distance using the formula:

There are several types of 'standard candle' objects for which we can predict the luminosity from some other measurement

Two of the most important are Cepheid variable stars and type 1A supernovae

Cepheid variables Cepheid variables are a special type of star with a luminosity which varies on a regular cycle

For distances which are too large to measure using parallax, astronomers use 'standard candles'

Light sources which are further away appear fainter because the light is spread out over a greater area

If we know how luminous a source really is, then we can estimate its distance from how bright it appears from Earth