Hubble's constant

noun

Astronomy.

1. the ratio of the recessional velocity of galaxies to their distance from the sun, with current measurements of its value ranging from 50 to 100 kilometers per second per megaparsec.

Word History and Origins

Origin of Hubble's constant¹

First recorded in 1950–55; after E. P. Hubble

Example Sentences

The universe is still expanding, at a rate of 73 kilometers per second per megaparsec, a metric known as Hubble's constant.

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Hubble’s law says the recession velocity of a galaxy is equal to its distance multiplied by a quantity called Hubble’s constant.

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To be precise, the time elapsed since the big bang is a function of the present value of Hubble’s constant and its rate of change.

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The value of Hubble’s constant seemed to be the same in all directions, a necessary consequence of uniform expansion.

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Hubble’s constant – proposed by Edwin Hubble in the 1920s – reveals by how much.

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