Is The Universe Expanding?

Is The Universe Expanding?

The universe is expanding at an accelerating rate, or is it?

Five years ago, the Nobel Prize in Physics was awarded to three astronomers for their discovery that the universe is expanding at an accelerating pace. Their conclusions were based on analysis of Type Ia supernovae -- the spectacular thermonuclear explosion of dying stars -- picked up by the Hubble space telescope and large ground-based telescopes. It led to the widespread acceptance of the idea that the universe is dominated by a mysterious substance named 'dark energy' that drives this accelerating expansion. Now, a team of scientists has cast doubt on this standard cosmological concept. The evidence for acceleration may be flimsier than previously thought, they say, with the data being consistent with a constant rate of expansion. Ref. Source 9z.