By Frank D. Roylance , frank.roylance@baltsun.com|May 11, 2009
The picture on Adam Riess' computer monitor arrived fresh from the orbiting Hubble Space Telescope. It was the fading light from an exploding star, potentially a key piece of evidence in his yearslong investigation of one of the greatest of all cosmological mysteries - dark energy.
But as the Johns Hopkins University astrophysicist waited for the next image to arrive, an e-mail message popped onto his screen. In an instant, he tumbled into what he describes as one of those "uh-oh" moments when everything changes.
Hubble's Advanced Camera for Surveys - or the part of it vital to his research - had shut itself down. And it was quickly apparent that it would not come back. Riess' work on the scientific puzzle that had made him famous was finished, maybe for years. Maybe forever.
That was more than two years ago, and Riess is one of hundreds of Marylanders whose jobs and passions will be riding on space shuttle Atlantis as astronauts attempt a grueling series of five spacewalks to upgrade and repair the famed Hubble telescope.
The three-day launch window opens Monday at 2:01 p.m. for Atlantis and its seven-member crew as they set out from Cape Canaveral to extend the life of history's most productive observatory by at least another five years, add two new, more powerful instruments and restore life to two others, including ACS.
But it would be hard to find anyone with more at stake than Riess.
He was just 29 years old in 1998 when he became the lead author on the first dark energy paper to be published. It turned out to be one of the most momentous discoveries in cosmology. Ever.
He and his team had used a peculiar class of exploding star, called Type Ia supernovae, as mile markers across the universe. By measuring each stars' brightness, they could calculate their distances. And by analyzing their light spectra, they could measure how fast the universe was expanding when the light left each star. By plotting that expansion rate over time, they discovered that the cosmos has been expanding at an accelerating rate for billions of years.
The discovery (also made independently by another team) was astonishing, as if his paper had reported they tossed a brick into the air and watched it zoom into space, instead of falling back to Earth. Gravity was supposed to slow the universe's expansion over time, not accelerate it. The unexplained force driving that acceleration was dubbed "dark energy."
