distance modulus

The distance modulus is a way of expressing distances that is often used in astronomy.

Distance to the star can be calculated from magnitude by the distance modulus:

True distance moduli require a further theoretical step, that is the estimation of the interstellar absorption coefficient.

The difference between the relative and absolute magnitude, the distance modulus, yields this estimate of the distance.

After adjusting for reddening due to interstellar dust, the distance modulus is estimated as 11.6 magnitudes.

Distance moduli are most commonly used when expressing the distance to other galaxies in the relatively nearby universe.

Also calculating absolute magnitude from distance modulus :

By comparing the apparent brightness of two supernovae (called as distance modulus), we can thus determine their relative distances.

This is known as the distance modulus, where d is the distance to the star measured in parsecs.

Visual distance moduli are computed by calculating the difference between the observed apparent magnitude and some theoretical estimate of the absolute magnitude.

The difference between absolute and apparent magnitudes is called the distance modulus, and astronomical distances, especially intergalactic ones, are sometimes tabulated in this way.

This can be compared to the apparent magnitude of the galaxy, which provides an estimate of the distance modulus and, hence, the distance to the galaxy.

The maximum volume can be approximated as a sphere with radius found from the distance modulus, using the object's absolute magnitude and the limiting apparent magnitude.

The difference in magnitude that was bridged in order to match the two groups is called the distance modulus and is a direct measure for the distance.

The distance modulus is the difference between the apparent magnitude (ideally, corrected from the effects of interstellar absorption) and the absolute magnitude of an astronomical object.

Thus a distinction is made between distance moduli uncorrected for interstellar absorption (whose values would overestimate the distance if used naively) and absorption-corrected moduli.

The first ones are termed visual distance moduli and are denoted by while the second ones are called true distance moduli and denoted by .

At a distance of 150pc, the distance modulus is 5.9 magnitudes providing a lower limit to the absolute magnitude of the companion of about 16 whether or not the candidate star is the binary companion.