The universe is expanding faster than previously believed, a surprising discovery that could test part of Albert Einstein's theory of relativity, a pillar of cosmology that has withstood challenges for a century.
The discovery that the universe is expanding 5 percent to 9 percent faster than predicted, announced in joint news releases by NASA and the European Space Agency, also stirs hypotheses about what fills the 95 percent of the cosmos that emits no light and no radiation, scientists said on Thursday.
"Maybe the universe is tricking us," said Alex Filippenko, a University of California, Berkeley astronomer and co-author of an upcoming paper about the discovery.