Big Bang

New Hubble constant measurement adds to mystery of universe’s expansion rate

In a new study, scientists announced a new measurement of the Hubble constant using a kind of star known as a red giant and indicated that the expansion rate for the nearby universe is just under 70 kilometers per second per megaparsec (km/sec/Mpc).

Assembling wide view of the evolving universe

Astronomers have put together the largest and most comprehensive "history book" of galaxies into one single image, using 16 years' worth of observations from...