Shuttle Flight Will Service Hubble Telescope, Extending Its Life: Griffin
The Hubble Telescope will live to provide further eye-opening scientific discoveries for a few more years, thanks to a decision by NASA Administrator Michael Griffin to send a space shuttle mission to service the eye in the heavens.
The $900 million rescue mission will lift off in spring to fall (perhaps May) of 2008, and should have but a minor financial impact on the future U.S. manned space exploration program.
Griffin said the decision will keep the Hubble functioning through 2013, when the James Webb Space Telescope will take the lead.
He thus effectively reversed a decision years ago to let the space telescope decay and slip from use, something that would occur in a couple of years without the shuttle servicing mission. This would be the fifth servicing mission for the telescope, and one that will make the Hubble better than it ever was.
There was no organized opposition within NASA to the Hubble rescue mission, Griffin indicated. “I don’t believe I’ve talked to anyone in the agency … who thinks we shouldn’t do this,” Griffin said.
Mission planners are working to determine the best location and vehicle in the manifest to support the needs of Hubble while minimizing impact to International Space Station (ISS) assembly, according to NASA. Space Shuttle Discovery might be deployed for the Hubble mission.
Once again, Griffin is making a gutsy decision with a potential significant payoff.
Just this year, he made a decision to let Space Shuttle Discovery fly, even though two key NASA officials made a no-fly recommendation based on safety concerns.
They were influenced by the Space Shuttle Columbia disaster in 2003, when the Columbia orbiter vehicle was hit by a large chunk of insulating foam that ripped loose from the external fuel tank shortly after launch began. The foam smashed a hole in the leading edge of a wing on the orbiter, which wasn’t seen by the crew or ground personnel, causing loss of the ship and crew during reentry.
But since then, changes were made in the remaining shuttles, including altered foam application moves.
The safety moves worked, and Griffin was right.
No large pieces of foam insulation broke off from the fuel tank during the launch of Space Shuttle Discovery on July 4, or in the launch of Space Shuttle Atlantis Sept. 9. And what few small specks of foam did tear loose were too late in the ascent to cause any major harm.
Also, Griffin in his Hubble shuttle mission decision considered the fact that the orbiter vehicle would be scanned minutely for any signs of damage, no matter how tiny. Thus it would be unlikely for another Columbia-style disaster to occur.
In part, his earlier decision process included the fact that those shuttles, Discovery and Atlantis, were on missions to the space station. That meant if either shuttle orbiter vehicle had been damaged, the shuttle crew could have used the ISS as a life raft.
In the Hubble mission, however, the space shuttle won’t be going to the ISS. While the shuttle orbiter will be examined carefully and repeatedly for damage after the ascent, if damage is discovered, the ISS won’t be there to use as a life raft.
But here again, Griffin has a safety fall-back move. In event the shuttle orbiter is found to have sustained damage during launch, NASA will have a rescue craft ready to launch, soaring aloft to pick up the stranded astronauts.
Planners are investigating the best way to support a launch-on-need mission for the Hubble flight. The present option will keep Launch Pad 39B at Kennedy Space Center, Fla., available for such a rescue flight should it be necessary.
“We would have another orbiter ready to fly,” William Gerstenmaier, associate administrator for space operations, said in a news conference following the Hubble rescue announcement. And this was no shoot-from-the-hip decision.
“We have conducted a detailed analysis of the performance and procedures necessary to carry out a successful Hubble repair mission over the course of the last three shuttle missions,” Griffin said.
Hubble Mission Safety Backed
“What we have learned has convinced us that we are able to conduct a safe and effective servicing mission to Hubble,” Griffin said. “While there is an inherent risk in all spaceflight activities, the desire to preserve a truly international asset like the Hubble Space Telescope makes doing this mission the right course of action.”
“The decision would always be based on the safety of our astronauts,” said Sen. Barbara A. Mikulski of Maryland, ranking Democrat on the Senate Appropriations Committee commerce, justice and science subcommittee. She spoke at the announcement of the Hubble mission, which came at the Goddard Space Flight Center, located in Mikulski’s home state. Goddard is the agency center responsible for managing Hubble.
She pledged to “make sure there is always money in the budget to protect our astronauts.”
Astronauts themselves have pointed out repeatedly that no space flight is totally safe or risk-free, including a mission such as the Hubble servicing that will involve multiple extra-vehicular activities (EVAs), or spacewalks.
The Hubble mission will have to be dovetailed into a very tight series of space shuttle launches required to complete construction of the ISS. For example, Atlantis carried a gigantic truss and solar array into orbit, which then was attached to the ISS and worked on during several EVAs. Discovery next month will carry another segment to be added to the ISS. (Please see story in this issue.)
NASA faces a daunting schedule averaging four shuttle missions yearly from now until 2010, when the shuttle fleet is slated to be retired.
Griffin also took issue with those who see NASA as neglecting science programs to free funds for manned space missions such as President Bush’s vision of journeys to the moon, Mars and beyond.
He pointed out that “there is absolutely nothing at NASA that isn’t science related,” including those missions.
And the Hubble Space Telescope has yielded a treasure chest of scientific marvels, with the rescue mission enabling the Hubble to continue unlocking mysteries of the universe for many more years.
Hubble Yields Priceless Science
The space telescope has provided myriad scientific gems, helping to push out the boundaries of astronomical knowledge.
Over a decade and a half, Hubble has seen hitherto unknown planets, plumbed deeper into space than ever seen in history, and helped scientists understand the origins of the universe.
One Hubble discovery was dark energy, some little-understood force that accelerates the expansion of the universe.
The telescope also has provided photographic evidence of supernovas, the death throes of huge stars as they explode.
And Hubble will be key in attempting to locate planets circling distant stars, planets that might be suitable for formation of life.
All the accomplishments thus far have come before upgrades that the Hubble rescue mission space shuttle crew will install on the telescope, such as new instruments.
The two new instruments are the Cosmic Origins Spectrograph (COS) and Wide Field Camera 3 (WFC3). The COS is the most sensitive ultraviolet spectrograph ever flown on Hubble. The instrument will probe the cosmic web, the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by the spatial distribution of galaxies and intergalactic gas.
WFC3 is a new camera sensitive across a wide range of wavelengths (colors), including infrared, visible, and ultraviolet light. It will have a broad inquiry from the planets in our solar system to the early and distant galaxies beyond Hubble’s current reach, to nearby galaxies with stories to tell about their star formation histories.
Other planned work includes installing a refurbished Fine Guidance Sensor that replaces one degrading unit of the three already onboard. The sensors control the telescope’s pointing system. An attempt also will be made to repair the Space Telescope Imaging Spectrograph. Installed in 1997, it stopped working in 2004. The instrument is used for high resolution studies in visible and ultraviolet light of both nearby star systems and distant galaxies, providing information about the motions and chemical makeup of stars, planetary atmospheres, and other galaxies.
The New Instrument Lineup
COS will measure the structure and composition of the ordinary matter concentrated in the “cosmic web,” long, narrow filaments of galaxies and intergalactic gas separated by huge voids. COS will use faint distant quasars as “cosmic flashlights,” whose beams of light pass through the cosmic web, NASA explained. Absorption of this light by “stuff” in the web reveals characteristics of that material. This allows scientists to determine its composition and its specific location in space.
These observations, covering vast distances across space and time, will illuminate both the large-scale structure of the universe and the progressive changes in chemical composition of matter as the universe has grown older.
The WFC3 will extend Hubble’s capability to see deep into the universe, with the power to observe in multiple wavelengths (colors) of light including infrared, visible and ultraviolet light. WFC3 can, for example, observe young, hot stars that glow predominantly in ultraviolet and older, cooler stars that glow predominantly in infrared in the same galaxy. The first stars and galaxies to form in the universe are so old and distant that their light is now relegated to infrared wavelengths. WFC3 could blaze a trail for the NASA’s future James Webb Space Telescope, scheduled for launch sometime in 2013.
Looking For Clues to A ‘Dark’ Mystery
The upgraded Hubble probably will not solve this dark energy dilemma, but it will make important contributions to narrowing down the range of possible explanations.
The mysterious dark energy is tied to the telescope’s namesake, Edwin Hubble, who discovered in the 1920s that the universe was expanding and taking all of its contents — galaxies, stars and planets — along for the ride. The rate of the expansion is now called the Hubble constant. Using Hubble and other observatories, scientists have concluded the universe is expanding.
Hubble Mission Crew Members
Griffin also announced the astronauts selected for the 11-day Hubble mission.
Veteran astronaut Scott D. Altman will command the final space shuttle mission to Hubble. Navy Reserve Capt. Gregory C. Johnson will serve as pilot. Mission specialists include veteran spacewalkers John M. Grunsfeld and Michael J. Massimino and first-time space fliers Andrew J. Feustel, Michael T. Good and K. Megan McArthur.
Altman, a native of Pekin, Ill., will be making his fourth spaceflight and his second trip to Hubble. He commanded the STS-109 Hubble servicing mission in 2002. He served as pilot of STS-90 in 1998 and STS-106 in 2000.
Johnson, a Seattle native and former Navy test pilot and NASA research pilot, was selected as an astronaut in 1998. He will be making his first spaceflight.
Chicago native Grunsfeld, an astronomer, will be making his third trip to Hubble and his fifth spaceflight. He performed five spacewalks to service the telescope on STS-103 in 1999 and STS-109 in 2002. He also flew on STS-67 in 1995 and STS-81 in 1997.
Massimino, from Franklin Square, N.Y., will be making his second trip to Hubble and his second spaceflight. He performed two spacewalks to service the telescope during the STS- 109 mission in 2002.
Feustel, Good, and McArthur each were selected as astronauts in 2000. Feustel, a native of Lake Orion, Mich., was an exploration geophysicist in the petroleum industry at the time of his selection by NASA. Good is from Broadview Heights, Ohio, and is an Air Force colonel and weapons’ systems officer. He is a graduate of the Air Force Test Pilot School, having logged more than 2,100 hours in 30 different types of aircraft.
McArthur, born in Honolulu, considers California her home state. An oceanographer and former chief scientist at the Scripps Institution of Oceanography, she has a doctorate from the University of California-San Diego.
“Hubble has been rewriting astronomy text books for more than 15 years, and all of us are looking forward to the new chapters that will be added with future discoveries and insights about our universe,” said Mary Cleave, NASA’s associate administrator for the Science Mission Directorate.
Following launch, the Hubble servicing shuttle will rendezvous with the telescope on the third day of the flight. Using the shuttle’s mechanical arm, the telescope will be placed on a work platform in the cargo bay. Five separate space walks will be needed to accomplish all of the mission objectives.
“The Hubble mission will be an exciting mission for the shuttle team,” Gerstenmaier said. “The teams have used the experiences gained from [post-Columbia flights] and station assembly to craft a very workable Hubble servicing flight. The inspection and repair techniques, along with spacewalk planning from station assembly, were invaluable in showing this mission is feasible.”
He added, “There are plenty of challenges ahead as the teams do the detailed planning and figure the best way to provide for a launch-on-need capability for the mission. There is no question that this highly motivated and dedicated flight control team will meet the challenge.”
The Hubble telescope, designed and built at Lockheed Martin Corp. [LMT] Space Systems in Sunnyvale, Calif., was launched in 1990. The company announced it will provide support for the servicing mission to the telescope.
It is an international cooperative project between NASA and the European Space Agency.