Donald Savage Headquarters, Washington, DC April 24, 1995 (Phone: 202/358-1547) Tammy Jones Goddard Space Flight Center, Greenbelt, MD (Phone: 301/286-5566) Ray Villard Space Telescope Science Institute, Baltimore, MD (Phone: 410/338-4514) RELEASE: 95-56 FIFTH ANNIVERSARY OF HUBBLE LAUNCH OBSERVED TODAY Today is the fifth anniversary of the launch of NASA's Hubble Space Telescope. Celebrated throughout the world as the finest astronomical instrument ever built, Hubble has provided remarkable new views of the universe which have revolutionized astronomers' thinking about a variety of current astronomical mysteries. "The Hubble Space Telescope is truly a national scientific treasure," said Dr. Wesley Huntress, Jr., NASA's Associate Administrator for Space Science. "With a rate of discovery that is unprecedented for any modern observatory, Hubble not only has revolutionized astronomy, it has engaged the interest and imagination of the public more than any space science satellite has done before. "And that may be its most far-reaching and important legacy -- getting a new generation of young people excited about science," Huntress said. Launch and First Three Years Launched April 24, 1990, on the Space Shuttle Discovery's STS-31 mission, the Hubble Space Telescope, with a resolving power calculated to be ten times better than any telescope on Earth, was poised to open a new era in astronomy. Within a few months, however, a flaw was discovered in Hubble's main mirror which significantly reduced the telescope's ability to focus. The focusing defect was due to spherical aberration, an optical distortion caused by an incorrectly shaped mirror. Instead of being focused into a sharp point, light collected by the mirror was spread over a larger area in a fuzzy halo. Images of objects such as stars, planets and galaxies were blurred. However, on relatively bright objects, Hubble's cameras were still able to provide images far superior to any telescope on the ground. Program and project management officials, working with the scientific community, developed a plan to take advantage of the telescope's instruments that were not affected by the aberration, such as ultraviolet and spectrographic observations. During its first three years of operation, Hubble provided significant new information and discoveries about the universe, including astonishing images of supernova 1987A and a disk of cold gas fueling a black hole. The team also began developing a corrective optics package that, together with a new camera already scheduled for installation in Hubble in 1993, would restore Hubble to its intended imaging capabilities. The two major instruments planned for installation, the Wide Field/Planetary Camera (WF/PC-II) and the Corrective Optics Space Telescope Axial Replacement (COSTAR), were designed to correct the aberration. WF/PC- II was designed so that the light reaching each of the instrument's four cameras was corrected by relay mirrors polished to a prescription compensating for the incorrect figure produced by Hubble's primary mirror. COSTAR routed properly focused light to three of Hubble's five instruments. Ball Corp. built Hubble's corrective optics for the Goddard Space Flight Center, Greenbelt, MD. The seven astronauts selected to service Hubble practiced for nearly a year-and-a-half. They spent hundreds of hours practicing and learning the uses of more than 100 different servicing tools. This mission would be one of the most challenging missions NASA had ever attempted. Servicing Mission Opens New Era On December 2, 1993, the STS-61 crew launched on Space Shuttle Endeavour for an 11-day mission with a record five spacewalks planned. Watched by millions worldwide on live television, the astronauts endured long hours of challenging spacewalks to install instruments containing the corrective optics and replaced the telescope's solar arrays, gyroscopes, and other electronic components. They installed WF/PC-II and replaced the High Speed Photometer with the COSTAR instrument. They also installed a new computer co-processor to upgrade the telescope's computer memory and processing speed, the Solar Array Drive Electronics unit and the Goddard High Resolution Spectrograph Redundancy Kit. The crew completed everything it set out to do and the mission was declared a success. After five weeks of engineering check-out, optical alignment and instrument calibration, the confirmation of success came as the first images were received on the ground from the space telescope. NASA Administrator Daniel Goldin was joined in announcing the successes by Dr. John Gibbons, Assistant to the President for Science and Technology, and Sen. Barbara Mikulski (D-MD), at a press conference at Goddard. "This is phase two of a fabulous, two-part success story," Goldin said at the press conference. "The world watched in wonder last month as the astronauts performed an unprecedented and incredibly smooth series of space walks. Now, we see the real fruits of their work and that of the entire NASA team." Not only has Hubble advanced science's understanding of the universe, it also is making direct contributions through a variety of technological spinoffs. During 1994 a new, non-surgical breast biopsy technique was developed using imaging Charge Coupled Devices, originally developed for Hubble's Imaging Spectrograph. This technology now enables doctors to precisely locate a suspicious lump in a woman's breast and use a needle, instead of a scalpel, to extract a sample of tissue for study. Looking Ahead The Hubble Space Telescope was designed to work on orbit for 15 years, providing an unparalleled observatory for astronomers well into the next century. To keep Hubble running smoothly, three additional servicing missions are planned, similar to but probably not as extensive as the first servicing mission in 1993. During the next servicing mission, scheduled for February 1997, astronauts will install two new instruments -- the Space Telescope Imaging Spectrograph and the Near Infrared Camera and Multi-Object Spectrograph. The third servicing mission, scheduled for November 1999, will see the installation of the Hubble Advanced Camera for Exploration, which will greatly enhance the telescope's imaging capabilities. Hubble's Ten Most Important Scientific Discoveries Hubble program and project scientists selected the following "top ten" list of discoveries from hundreds of findings made over the past five years by scientists using Hubble. The selections were based on their scientific merit and long-term importance in advancing the field of astronomy. Since it became operational in 1990, NASA's Hubble Space Telescope: * Offered the first conclusive evidence for the existence of immense black holes, millions or billions of times the mass of Earth's Sun. * Showed that the universe might be much younger than had been previously thought. This was accomplished by calculating the universe's expansion rate based on an accurate Hubble distance measurement to a remote galaxy. * Gave the first direct visual evidence that the universe is evolving as predicted in Big Bang cosmology, by resolving the shapes of the farthest galaxies ever seen. * Discovered that quasars, very distant and remarkably bright objects, are even more mysterious than commonly thought because many do not dwell in the cores of galaxies, but are isolated in space. * Suggested that dark matter in the universe is more exotic than previously thought, by finding that nature doesn't make enough of the extremely small Red Dwarf stars that were once a leading candidate for the universe's "missing mass." * Supported the Big Bang theory by refining estimates of the amount of deuterium in space, an element created in the initial cosmic fireball that gave birth to the universe. * Solved the mystery of intergalactic clouds of hydrogen by showing that they are really gigantic halos of galaxies. * Implied that planets, and presumably life, might be abundant in the universe by discovering disks of dust that might be embryonic planetary systems around young stars. * Provided important details and surprising findings of the spectacular collisions of comet Shoemaker-Levy 9 with Jupiter last year. * Revealed dynamic weather changes on nearly all the planets with a clarity once attainable only with spacecraft flybys. Scientists found that most planets' atmospheres are much more active than previously believed, and the ability of Hubble to 'revisit' the planets allows frequent monitoring similar to Earth weather satellites. A Photo Gallery Of The Universe: The Best Of Hubble Images 1990-1995 Hubble Space Telescope's dramatic images evoke a sense of awe and wonder. The following is a selection of Hubble's ten most spectacular and important images, selected on the basis of scientific value as well as aesthetic content. The images are available in color or B&W prints or via the Internet in a special Hubble 5th Anniversary Home Page. See Editor's Note following this release for information on obtaining images or accessing the home page. SUPERNOVA 1987A - HALO FOR A VANISHED STAR An eerie, nearly mirror-image pair of red luminescent gas "hula-hoops" framing the expanding debris of a star was seen as a supernova explosion in 1987. April 1994. NASA photo number: 94-HC-39 THE ORION NEBULA - STELLAR BIRTHPLACE An immense wall of glowing gases forms a colorful backdrop to dozens of newborn stars, many of which have dust disks -- as revealed by Hubble -- that might be embryonic solar systems. January 1994. NASA photo number: 94-HC-163 THE RING GALAXY - RESULT OF A BULL'S-EYE COLLISION A spectacular head-on collision between a spiral galaxy and a smaller intruder sends out a ripple of energy that triggers a firestorm of new star birth, forms a dazzling ring-like structure. January 1995. NASA photo number: 95-HC-23 COMET P/SHOEMAKER-LEVY 9 BOMBARDS JUPITER Hubble followed unexpected and dramatic changes in Jupiter's atmosphere caused by collisions with comet fragments. The titanic blasts left Jupiter with a temporary "bruised" appearance, caused by black debris that was tossed high above the giant planet's cloud tops. July 1994. NASA photo number: 94-HC-188 SPIRAL GALAXY M100 A majestic pinwheel formed by hundreds of billions of stars harbors rare pulsating stars that can yield clues to the size and age of the universe. The galaxy is so far away, Hubble sees it as it appeared at about the time dinosaurs roamed the Earth. January 1994. NASA photo number: 94-HC-280 SATURN STORM A rare storm, large enough to swallow Earth, appears near Saturn's equator. High altitude winds give the storm a distinctive arrowhead shape. January 1994. NASA photo number: 94-HC-556 RING AROUND A SUSPECTED BLACK HOLE IN GALAXY NGC 4261 The gravitational pull of a suspected super-massive black hole forms a Frisbee-like disk of cool gas, at the core of an energetic galaxy. Subsequent Hubble observations of yet another active galaxy confirmed the reality of monstrous black holes -- gravitational "sink holes" that trap everything, even light. November 1992. NASA photo number: 92-HC-708 PLANETARY NEBULA NGC 6543, GASEOUS COCOON AROUND A DYING STAR Mysterious stellar fireworks create expanding gas shells and blowtorch-like jets which form a spectacularly intricate and symmetrical structure. The nebula is a fossil record of the late stages of the star's evolution. January 1995. NASA photo number: 95-HC-24 CYGNUS LOOP - BLAST WAVE FROM A STELLAR TIME-BOMB High speed gas from a supernova explosion slams into dark cooler clouds of interstellar material. Shocked and heated by this tidal wave of energy, the clouds glow in bright, neon-like colors. February 1995. NASA photo number: 95-HC-77 WEATHER FORECAST FOR MARS Wispy clouds, a melting polar ice cap, and a dust- storm free surface all indicate a cool, clear spring time in the Martian northern hemisphere. Hubble also is serving as a weather satellite for studying the climate on other planets. February 1995. NASA photo number: 95-HC-115 The Space Telescope Science Institute is operated by AURA (the Association of Universities for Research in Astronomy, Inc.) for NASA, under contract with the Goddard Space Flight Center, Greenbelt, MD. The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. - end - EDITOR'S NOTE: The HST Top Ten Images are available to news media representatives by calling the Headquarters Broadcast & Imaging Branch at 202/358-1900, the Goddard Space Flight Center at 301/286-8956 or 286-7277, or the Space Telescope Science Institute at 410/338-4562 (use the NASA photo number listed for each image). The "Top Ten Images" also are available via the Internet in a special Hubble 5th Anniversary Home Page in GIF, JPEG and TIFF formats. Users can access this page using the following protocol: * Anonymous ftp to ftp.stsci.edu: GIF files are in /pubinfo/gif, with extension ".gif" JPEG files are in /pubinfo/jpeg, with extension ".jpg" TIFF files are in /pubinfo/tiff, with extension ".tif" * WWW -- follow links in http://www.stsci.edu/pubinfo/BestOfHST95.html or browse directories using http://www.stsci.edu/ftp/pubinfo and links to gif, jpeg and tiff NASA press releases and other information are available automatically by sending an Internet electronic mail message to domo@hq.nasa.gov. In the body of the message (not the subject line) users should type the words "subscribe press-release" (no quotes). The system will reply with a confirmation via E-mail of each subscription. A second automatic message will include additional information on the service. Questions should be directed to (202) 358-4043.