Dark Matter

Refined Hubble Constant Narrows Possible Explanations for Dark Energy:

The new value for the expansion rate, known as the Hubble constant, or Ho (after Edwin Hubble who first measured the expansion of the universe nearly a century ago), is 74.2 kilometers per second per megaparsec (error margin of ± 3.6). The results agree closely with an earlier measurement gleaned from Hubble of 72 ± 8 km/sec/megaparsec, but are now more than twice as precise.

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