Hubble's constant


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Related to Hubble's constant: Hubble diagram, Hubble time

Hub·ble's constant

 (hŭb′əlz)
n.
A ratio used in Hubble's law to express the rate of apparent expansion of the universe, equal to the velocity at which a typical galaxy is receding from Earth divided by its distance from Earth, approximately 71 kilometers per second per megaparsec.

[After Edwin Powell Hubble.]

Hubble's Constant

In 1924, Edwin P. Hubble discovered that the farther away a galaxy is, the faster its apparent speed. The speed-to-distance ratio is the constant, now measured at 30–60 mi/sec (50–100 km/sec) per million parsecs.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.Hubble's constant - (cosmology) the ratio of the speed of recession of a galaxy (due to the expansion of the universe) to its distance from the observer; the Hubble constant is not actually a constant, but is regarded as measuring the expansion rate today
cosmogeny, cosmogony, cosmology - the branch of astrophysics that studies the origin and evolution and structure of the universe
constant - a number representing a quantity assumed to have a fixed value in a specified mathematical context; "the velocity of light is a constant"
References in periodicals archive ?
The newly estimated expansion rate of the universe, known as Hubble's constant, is 67.
With this relation, obtained value of the present Hubble's constant is 70.
But tell me, what isn't being said when in the April 23 issue you report the value of Hubble's constant to be 70.
From Plato's erroneous promulgation that the planets have circular orbits to calculation in 2003 of Hubble's constant, Fraser (history and philosophy of science and technology, U.