Exploding stars shed more light on dark energy

Scientists report observations of supernovas from billions of years ago help prove that a force called dark energy was pushing the universe apart even back then.

They still do not understand dark energy -- which appears to be everywhere, pushing everything apart with its repulsive power. But now they may be on the right track.

"We think this is a significant clue in the quest to understand what is probably one of the most, if not the most, pressing questions in physics," said astrophysicist Adam Riess of Johns Hopkins University and NASA's Space Telescope Institute.

And their findings, made with the help of the orbiting Hubble Space Telescope, suggest that Albert Einstein was right yet again when he predicted that an energy force, which he called the Cosmological Constant, permeated the universe.