Hubble’s law
Quick Summary
Hubble's law, also known as the Hubble-Lemaître law, is a fundamental concept in cosmology that describes the expansion of the universe. It states that the velocity at which a galaxy recedes from Earth is directly proportional to its distance from us. This relationship was established by astronomer Edwin Hubble in 1929, building on earlier observations of galactic redshifts.1234
The law is expressed as: velocity = H0 × distance, where H0 is the Hubble constant. This constant represents the rate of the universe's expansion and is measured in kilometers per second per megaparsec. Modern estimates for the Hubble constant are around 67-72 km/s/Mpc. The reciprocal of the Hubble constant provides an approximate age for the universe, estimated to be between 13 and 14 billion years. Hubble's discovery provided crucial empirical support for the idea of an expanding universe originating from a big bang.1325
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redshift…basis for what is called Hubble’s law, which correlates the recessional velocity of a galaxy with its distance from Earth. That is to say, the greater the redshift manifested by light emanating from such an object, the greater the distance of the object and the larger its recessional velocity (see…
Read More…basis for what is called Hubble’s law, which correlates the recessional velocity of a galaxy with its distance from Earth. That is to say, the greater the redshift manifested by light emanating from such an object, the greater the distance of the object and the larger its recessional velocity (see…
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astronomyDetermining astronomical distances…correlation is expressed in the Hubble law: velocity = H × distance, in which H denotes Hubble’s constant, which must be determined from observations of the rate at which the galaxies are receding. There is widespread agreement that H lies between 67 and 73 kilometres per second per megaparsec (km/sec/Mpc).…
Read More…correlation is expressed in the Hubble law: velocity = H × distance, in which H denotes Hubble’s constant, which must be determined from observations of the rate at which the galaxies are receding. There is widespread agreement that H lies between 67 and 73 kilometres per second per megaparsec (km/sec/Mpc).…
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