Calculate Distance and Expansion with the Hubble Constant
Calculator for the Hubble constant, which indicates the rate of expansion of the universe from the distance of the galaxies. The exact value of the Hubble constant is not yet known, depending on the measurement method, it is determined to be about 67 or 72 kilometers per second per megaparsec. In fact, it is not a constant as it changes over time. It is therefore also referred to as the Hubble parameter. The process of expanding the universe is called the Hubble flux. Please enter two values to calculate the third value. The calculator does not check the correctness or plausibility of the entered values.
Example: a galaxy one billion light-years away (1 Gly) is receding from us at a Hubble constant of 72 at a speed of 22074.825 kilometers per second, or 7.363 percent of the speed of light (%c).
The Hubble constant was named after Edwin Hubble, who was one of the discoverers of the expansion of the universe in the 1930s. This discovery occured from the redshift of distant galaxies. Objects that emit light are shifted towards the red in the spectrum as they move away from us. This is the optical Doppler effect, which works like the acoustic Doppler effect. The receding object emits electromagnetic waves, but each trough and crest of the wave arrives from a slightly greater distance than the previous one. This stretches the incoming wave and distorts it towards longer wavelengths. And longer wavelength in visible light is towards red. In the case of light, this effect is only measurable at very high speeds, which galaxies usually have. However, the redshift tends to be greater the further away the galaxy is, which suggests an expanding universe.
Last updated on 06/30/2025. Author: Jürgen Kummer
Physics Calculators | © Jumk.de Webprojects | Online Calculators
Imprint & Privacy | German: Elektromagnetisches Spektrum
Retrieved on 2026-04-22 from https://rechneronline.de/spectrum/hubble-constant.php