A dramatic new photo taken by the Hubble Space Telescope to mark the observatory's 25th anniversary, showing a cluster of hot young stars shining in the heart of a nursery-like nebula some 20,000 light years from Earth, serves as a reminder of Hubble's enormous impact on astronomy and a glimpse of things to come, NASA's administrator said Thursday.
Speaking at the Newseum in Washington, NASA Administrator Charlie Bolden, who served as pilot of the shuttle Discovery for Hubble's launch on April 24, 1990, said the astronauts all knew Hubble "was going to be something special. What we didn't realize was how special it really was going to be."
"Frankly, we never even thought the telescope would last this long," he said. "The original plan for Hubble, we were told, was maybe 15 years. The fact that we're still going strong a quarter century later is thanks to the Hubble heroes -- the scientists, the engineers and the astronauts who flew five missions to service Hubble in space."
The photo chosen to mark the telescope's 25th anniversary shows a young cluster of about 3,000 stars known as Westerlund 2 embedded in a vast cloud of gas known as Gum 29 in the southern constellation Carina.
The stars are among the hottest, brightest and most massive suns in the local neighborhood, releasing intense ultraviolet radiation and stellar "winds" that help shape the surrounding nebula.
"The brilliant stars sculpt the gaseous terrain of the nebula and help create a successive generation of baby stars," according to a NASA description of the image. "When the stellar winds hit dense walls of gas, the shockwaves may spark a new torrent of star birth along the wall of the cavity.
"The red dots scattered throughout the landscape are a rich population of newly-forming stars still wrapped in their gas-and-dust cocoons. These tiny, faint stars are between 1 million and 2 million years old -- relatively young stars -- that have not yet ignited the hydrogen in their cores. The brilliant blue stars seen throughout the image are mostly foreground stars."
The anniversary image merges visible light data from Hubble's Advanced Camera for Surveys and infrared images taken by the Wide Field Camera 3.
"As Frank Sinatra used to sing, the best is yet to come," Bolden said. "Thanks to the last servicing mission in 2009, Hubble is expected to continue to provide valuable data until 2020 and beyond. With two-and-a-half decades of historic, trail-blazing science already accomplished, we've come to realize and expect that there is still much more out there to discover."