Lost and Found: Hubble Finds Much of the Universe's Missing Hydrogen

For the past decade astronomers have looked for vast quantities of hydrogen that were cooked up in the Big Bang but somehow managed to disappear in the empty blackness of space. Now, NASA's Hubble Space Telescope has uncovered this long-sought missing hydrogen. This gas accounts for nearly half of the "normal" matter in the universe -- the rest is locked up in galaxies. The confirmation of this missing hydrogen will shed new light on the large-scale structure of the universe. The detection also confirms fundamental models of how so much hydrogen was manufactured in the first few minutes of the universe's birth in the Big Bang.

Illustration Credit:John Godfrey (STScI)