HAPPY BIRTHDAY TO HUBBLE

HAPPY BIRTHDAY TO HUBBLE
by Alan Boyle, April 24, 2007

Today marks the 17th anniversary of the Hubble Space Telescope's "birth" in space, and in a reversal of the usual routine, it's traditional for the Hubble team to give a gift. This time, astronomers are offering a wide-angle panorama of the Carina Nebula - a blazing-hot cosmic cookery that may be much like the environment that gave rise to our own solar system.

"It's one of the biggest and brightest star-forming regions in the sky," Nathan Smith, an astronomer at the University of California at Berkeley, told me Monday. "But this is the first time we've taken a large-scale view with the Hubble Space Telescope."

In fact, the Carina picture is one of the largest panoramic images ever taken with Hubble's cameras - more than 423 megapixels' worth, assembled from 48 frames taken with the Advanced Camera for Surveys.

The finished image shows a 50-light-year-wide inferno where ultraviolet radiation from monster stars carve into the landscape of cool gas and dust. About a dozen of the stars are thought to be at least 50 to 100 times as massive as our sun. One of those stars is Eta Carinae, a popular observational target that is in the last stages of its brief, explosive life. In this picture, Eta Carinae is just one bright blip toward the left edge of the frame. This annotated image helps you locate Eta Carinae and other major features in the panorama.

The winds of radiation from the brightest stars compress the surrounding shells of cold hydrogen gas, sparking a second wave of starbirth. How does this chain reaction work? To figure that out, astronomers color-coded the image, using additional data from the Cerro Tololo Inter-American Observatory in Chile. Red represents sulfur, green stands for hydrogen, and blue corresponds to oxygen emissions.

Smith, a leader of the research team behind the image, said the new image gave him a clearer picture of what's going on within the nebula. "With a 10 times sharper view, we have a much higher degree of certainty than before," Smith said.

For example, earlier pictures revealed bright linear features coming out of the darker regions of the nebula - and Hubble's sharper image confirmed exactly what those features were.

"We see them very clearly to be jets of ionized gas, coming out of globules of molecular gas and dust," Smith said. "What that signifies is that there's a star being born inside that dark cloud that's ejecting this material. ... It's proof that star formation is occurring there."

Studying the nebula, with Hubble as well as other telescopes, could tell astronomers whether planets are capable of forming amid the harsh conditions seen in places like the Carina Nebula. And the effort also could tell us something about the origins of our own solar system, 4.6 billion years ago.

"There's evidence that our own solar system was exposed to the death of a very massive star when it was young. ... Here we have a laboratory where we see young stars forming right now, right next to massive stars that are going to explode," Smith said. "That gives us a window to the environment where we think our own solar system might have formed."

Today's birthday portrait is just one of the nearly 500,000 pictures taken by Hubble since its launch aboard the shuttle Discovery on April 24, 1990. The Hubble team calculates that the space telescope has made nearly 100,000 trips around Earth, racking up 2.4 billion frequent-flier miles in the process - the equivalent of a trip to Saturn and back.

More than 30 trillion bytes of data have been sent back to Earth over those 17 years. Each day, another 10 billion bytes come back to Earth, and 66 billion bytes of data are transmitted from Hubble's archives to astronomers throughout the world. Hubble's team says all those bytes have spawned nearly 7,000 scientific papers, making the telescope "one of the most productive scientific instruments ever built." This 6.5-megabyte PDF file hits Hubble's high points.

How long will Hubble last? NASA wants to upgrade the telescope one last time, and that final servicing mission is now scheduled to lift off in August or September of 2008. Mission planners figure that should keep Hubble in good shape until 2013. By that time, NASA hopes the James Webb Space Telescope will be ready for launch, with Hubble eased into retirement at the ripe old age of 23.

Who knows? Maybe even then, there'll be some life left in the old telescope. So here's wishing Hubble and its handlers a happy 17th birthday ... and many more to come. For more stunners from space, check out our Space Gallery, as well as the Hubble Web sites maintained by the Space Telescope Science Institute and the European Space Agency.

Source : HAPPY BIRTHDAY TO HUBBLE article on MS NBC