Dark Matter

With proof in hand of a successful Hubble Space Telescope repair mission, NASA has shown that it can still be the "can-do" agency that put men on the moon and sent probes to the farthest planets. Last week's "first light" tests through the refurbished instrument returned razor-sharp pictures that met or exceeded scientists' most sanguine predictions for clarity and resolution.The planning and execution of the complex mission is already being ranked as one of the space age's most spectacular successes to date.

Seeing may be believing, but now it appears that nature consists of more than meets the eye. Last week, astrophysicists at the Space Telescope Science Institute in Baltimore and the National Optical Astronomy Observatories in Tucson, Ariz., reported a startling discovery that could profoundly alter our perception of the universe -- and indeed our most deeply-rooted conceptions of reality itself.Using their instruments to peer deep into space, they found that the local group of galaxies that includes our Milky Way is speeding in the direction of the constellation Virgo, apparently drawn by the gravitational pull of an enormous but invisible concentration of matter there.

CLEVELAND - Astronomers said yesterday that they had determined the time in cosmic history when a mysterious force, "dark energy," began to wrench the universe apart. Some 5 billion years ago, said Adam Riess, an astronomer at the Space Telescope Science Institute in Baltimore, the universe experienced a "cosmic jerk." Before then, he said, the combined gravity of the galaxies and everything else in the cosmos was resisting the cosmic expansion, slowing it down. Since the jerk, though, the universe has been speeding up. The results were based on observations by a multinational team of astronomers using the Hubble Space Telescope to search out exploding stars known as Type 1a supernovae, reaching back in time three-quarters of the way to the big bang in which the universe was born.

When it was launched in 1990, astronomers predicted that the powerful new Hubble Space Telescope would upset a lot of theoretical apple carts on its way to new discoveries.Three new reports from Hubble astronomers, including one described as "revolutionary," have proven those forecasts correct.The discoveries are challenging previous theories relating to gravitational "lenses," intergalactic hydrogen clouds and the chemistry of the early universe. Hubble's contributions to the debate were being discussed today before the 179th meeting of the American Astronomical Society in Atlanta.

Adam Riess studies exploding stars known as supernovas, so he's used to making surprising discoveries in space. But yesterday's biggest surprise was a message in his inbox -- telling him he will share a $1 million prize for his work in astronomy. "I woke up in the morning to check my e-mail, and there was a message from a Hong Kong reporter asking if he could interview me about winning the Shaw Prize," said Riess, 36, an astronomy professor at the Johns Hopkins University who shared in the 1998 discovery that the universe is expanding faster as time goes on. A fax later in the day confirmed he had been awarded the Shaw Prize, an international award given each year to scientists who make groundbreaking discoveries in astronomy, life sciences and medicine, and mathematics.

YOU'VE GOT YOUR business meetings, and then you've got your business meetings. All they did at the meeting of the American Astronomical Society was find 40 billion new galaxies and account for half the missing matter in the universe. Oh -- and raise the possibility of life on other planets.Must have been a fun couple of days.Did you happen to catch any of those stories coming out of San Antonio, where the stargazers were gathered last week for their latest celestial show-and-tell? Talk about playing ''Can You Top This?

PITTSBURGH -- Dr. Gibor Basri went looking for brown dwarfs and says he's found one.Dr. Basri is an astronomer at the University of California at Berkeley, and the brown dwarf he sought is a kind of star long thought to exist in a broad gap between the smallest known stars and the biggest planets."

Space shuttle Endeavour's record-long stargazing flight was extended to at least 16 1/2 days because of stormy weather at the landing site yesterday.The delay, after more than two weeks of round-the-clock work with a $200 million set of ultraviolet telescopes, left the crew a full day to rest and look out the window.The telescopes had already been packed away for the ride home Thursday night, just after scientists on the ground had a little fun with the crew.As they were preparing to shut down their equipment, Endeavour astronauts saw something strange on the TV monitor that displays what the telescopes are seeing.

Placing them in a select group of talented young scientists, two high school seniors from Howard County and two from Montgomery County have been named finalists in the Westinghouse Science Talent Search.Josh Greene, 17, of Oakland Mills High, and Sabyasachi Guharay, 17, of Wilde Lake High, each will each receive at least $1,000. One could receive as much as $40,000 if awarded the first-place prize.Perhaps more important, the highly competitive award is a flattering resume-booster for young scientists preparing for college.

"The Whole Shebang," by Timothy Ferris. Simon & Schuster. 393 pages. $25.Reading "The Whole Shebang" is like reading poetry in translation from Navajo. It's a good translation. Nevertheless you feel that you're missing something.Timothy Ferris has set himself a humorously difficult task: explaining for the layperson, in 393 pages, life, the universe and everything: in short, cosmology. Ferris, a physicist and prize-winning popular science writer, is qualified for the job if anyone is.In a time when the gulf between scientists and the rest of us is growing exponentially, any effort to explain the cutting edge of -- science to an intelligent layperson should be applauded.