 This is a story about catching rays, the kind that lure us here, and the kind that show doctors unseen parts of the human body. But this is not a story about getting a better tan or making better medicine. Instead, this is a story about NASA and astronomers, about the Space Shuttle, Space Lab, and a sensitive observatory that may show us our universe in a whole new light. For 10 days in May, a Space Lab mission called Astro-1 will focus its ultraviolet and X-ray telescopes on places far beyond our reach. Its sensitive instruments will catch the rays, ultraviolet and X-ray messages, that is, from these distant places. These messengers, invisible to the human eye, will bring new information about exploding stars that forge the elements used to make new stars, planets, and even life itself. About tiny stars where a sugar cube of matter weighs as much as a billion tons. About mysterious objects that shine with the brilliance of 10 trillion of our own suns. And about so-called black holes in the very fabric of space that are so gravitationally strong that neither matter nor light can escape from them. Astro-1 will show us a violent, ever-changing universe. Unlike the peaceful serene heavens, we see with the naked eye or from ground-based optical telescopes. But why does this astronomy have to be done in space? When we look at the light from stars and galaxies from the ground, we really don't see all of it. Most stars and galaxies emit a lot of light that doesn't reach the ground. That's because our atmosphere acts like a protective blanket, shielding us from all of the message-carrying ultraviolet and X-rays. Well, almost all of them anyway. But in space, this radiation is a rich, barely-tapped resource of information about the universe. Astro-1 will open our eyes to the knowledge hidden in the invisible universe. This is the first opportunity we've ever had to place an observatory like this in outer space manned by astronaut astronomers. And it will forward us an opportunity to take a view of the universe such as we've never seen it before. We'll be able to look at celestial objects with ultraviolet telescopes and an X-ray telescope. And this is going to tell us a whole lot about the composition of our universe, the history of the universe, and the future of the universe. Astro-1 is a team effort. Astronomers in space will operate the telescopes. They will work with astronomers on the ground in a brand-new Space Lab Control Center at NASA's Marshall Space Flight Center in Huntsville, Alabama. Other astronomers will participate from a facility at the Goddard Space Flight Center in Greenbelt, Maryland. Together they are in search of knowledge, trying to prove the expected, always anticipating the unexpected. Surprises come. In fact, that's the fun thing about science. And I think that's the thing that drives most of us involved with astro. We think we understand what these objects are and what radiation they're going to emit when we go and measure them in the ultraviolet or X-radiation. But we know that they're going to be unanticipated discoveries. People once stood on the beach and looked to the horizon at what they believed was a flat whirl. Again, explorers took to the vast unknown, returning information that forever changed human thought. Perhaps we are standing on a similar coastline, awaiting discoveries that could lead us to a whole new understanding of our universe. Thanks to Astro-1 and other Space Lab missions to follow, we may soon find out.