Hubble constant value tagged posts

Researchers have discovered an unusual pulsar – one of deep space’s magnetized spinning neutron-star ‘lighthouses’ that emits highly focused radio waves from its magnetic poles. It is unusual because the masses of its two neutron stars are quite different — with one far larger than the other. The breakthrough provides clues about unsolved mysteries in astrophysics — including the expansion rate of the Universe (the Hubble constant).

The newly discovered pulsar (known as PSR J1913+1102) is part of a binary system — which means that it is locked in a fiercely tight orbit with another neutron star.

Neutron stars are the dead stellar remnants of a supernova...

3 steps astronomers used to measure the universe’s expansion rate (Hubble constant) to an unprecedented accuracy, reducing the total uncertainty to 2.3 percent. The measurements streamline and strengthen the construction of the cosmic distance ladder, which is used to measure accurate distances to galaxies near to and far from Earth. The latest Hubble study extends the number of Cepheid variable stars analyzed to distances of up to 10 times farther across our galaxy than previous Hubble results

Astronomers have used Hubble to make the most precise measurements of the expansion rate of the universe since it was first calculated nearly a century ago. Intriguingly, the results are forcing astronomers to consider that they may be seeing evidence of something unexpected at work in the universe...