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March 9, 1999

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NASA pulls plug on WIRE science mission

The first mission in a new NASA program aimed at finding life elsewhere in the cosmos ended Monday when a freshly-launched satellite was essentially declared dead.

Tumbling in space since its Thursday liftoff, the $54 million spacecraft exhausted its supply of a critical coolant, making it impossible to operate an onboard telescope to study the birth of stars and galaxies.

"We are very disappointed at the loss of (the satellite's) science program," said NASA space science chief Ed Weiler.

He added an investigation into the failure of NASA's Wide-Field Infrared Explorer - WIRE for short - is underway.

Frozen hydrogen was supposed to cool the craft's telescope during a four-month mission, but the coolant began spewing out shortly after launch. That sent the spacecraft it into a spin.

Experts think the trouble was caused when a telescope cover popped off, allowing the coolant to heat and escape. Without the coolant, heat from the telescope overwhelms faint infrared light from faraway stars, planets and galaxies.

Weiler said the mission will be somewhat salvaged with a plan to right the craft and try to use its advanced communications and data handling systems for engineering tests.

The flight was the first for NASA's Origins Program, which aims to determine how life on Earth arose and if it exists elsewhere in the universe.

The craft would have shed light on how and when stars and galaxies formed.

That would have helped scientists understand the processes which lead to the birth of sun-like stars and Earth-like planets elsewhere in the universe.


NASA-Goddard Status Report for Saturday, March 6

Efforts to establish control of the Wide-Field Infrared Explorer (WIRE) spacecraft are continuing.

The spacecraft continues to spin, but the rate of spin has stabilized at about 60 revolutions per minute. Last night, controllers sent commands to the spacecraft to see if the telescope could be gently moved in order to reduce solar input. However, imparting even the extremely light magnetic countering force on the rotating spacecraft caused the spacecraft's solar arrays to begin oscillating and the maneuver was stopped.

"We are still hopeful that we can take advantage of the fact that WIRE's rotation rate has finally stabilized, but our efforts last night proved we have to develop a different scheme," said Jim Watzin, Small Explorer Project Manager. "We are totally focused on gaining full control of WIRE and we won't do anything to jeopardize other systems."

Watzin said the WIRE team is devising a new plan which will involve building a software program that would use the spacecraft's onboard attitude control system to "de-spin" the spacecraft." Watzin said it would take several days to develop this software package.

WIRE was launched March 4 at 9:57 p.m. EST on from Vandenberg Air Force Base, Calif. Ground controllers determined that WIRE was spinning instead of maintaining a stable position in orbit and was warmer than expected. The spacecraft carries frozen hydrogen to cool its instrument. Controllers believe the hydrogen is venting as it warms up, causing the spacecraft to spin. Spacecraft controllers do not know what specifically caused the situation.

The WIRE team is communicating with the spacecraft. "The subsystems are in good shape," said Watzin. "The solar arrays are generating power and the battery is fully charged. We have plenty of power to effect a recovery."

The next WIRE update will be released on March 8.


NASA Headquarters, Washington, DC
Goddard Space Flight Center, Greenbelt, MD

March 5, 1999

NASA WORKING TO CORRECT SPIN RATE OF WIRE SPACECRAFT

Ground controllers are attempting to recover a NASA spacecraft that was unable to maintain a stable position in orbit after launch Thursday.

The Wide-Field Infrared Explorer (WIRE) spacecraft began to experience a problem during its second pass over a ground station, following a successful launch at 9:57 p.m. EST from Vandenberg Air Force Base, CA. The Poker Flats, AK, ground station determined that WIRE was still spinning instead of maintaining a stable position in orbit and was warmer than expected. The WIRE team has declared a spacecraft emergency and is communicating with the spacecraft while attempting to slow the spin rate and cool the WIRE spacecraft.

"Recovery of the spacecraft is our top priority," said Ken Ledbetter, Director of the Mission and Payload Development Division in the Office of Space Science at NASA Headquarters, Washington, DC. "The spacecraft carries frozen hydrogen to cool its instrument, and we believe that the hydrogen is venting as it warms up, causing the spacecraft to spin. However, at this time, spacecraft controllers do not know what specifically caused the situation."

A spacecraft recovery team has been formed, headed by David Everett of NASA's Goddard Space Flight Center, Greenbelt, MD. In addition to the recovery team, an anomaly investigation board is being formed.

Further updates will be released as information concerning WIRE's anomaly is obtained.


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NASA's WIRE mission short-circuits just after launch

A $46 million NASA spacecraft is tumbling through space today as ground controllers scramble to save the inaugural mission in a program aimed at determining if life exists elsewhere in the cosmos.

And while mission managers haven't declared the satellite dead yet, the craft was in critical condition Friday.

Consequently, the telescope-toting explorer probably won't be able to complete a planned four-month mission to study the birth of stars throughout the universe.

"It certainly will not be four months," said Ken Ledbetter, director of payload development at NASA Headquarters in Washington, D.C. "And the longer it takes (to right the spacecraft) the shorter the mission will be."

Lofted into space late Thursday by an air-launched Pegasus rocket, the Wide-Field Infrared Explorer spacecraft is equipped with a 560-pound telescope that was designed specially to study the formation of stars, planets and galaxies.

To do that, the infrared telescope was wrapped in a jacket of supercold hydrogen ice and then housed in a device similar to a thermos bottle.

Stored at Minus 438 degrees Fahrenheit, the frozen hydrogen serves as the critical coolant the telescope needs to collect faint infrared light given off by celestial targets.

Without it, the glow of heat from the telescope itself would overwhelm the dim points of infrared light the small observatory is attempting to detect in deep space.

Engineers think the so-called WIRE mission began to go awry when a telescope cover inadvertantly popped off after the craft reached an orbit 335 miles above Earth.

Heat streaming into the spacecraft probably caused the frozen hydrogen to sublimate - or turn from a solid to a gas - at a much more rapid pace than planned.

Engineers think pent-up hydrogen gas then began shooting out of spacecraft vents, sending the craft into a tumble.

Ground controllers were attempting to right the spacecraft so it could be turned away from the sun. The idea is to cool the craft enough so that its limited store of frozen hydrogen won't be wasted away.

The tumbled, however, must be stopped quickly if mission is to be saved.

"Certainly we don't have weeks - we've only got days - if we continue at the rate that (the coolant) is venting," Ledbetter said. "So we're proceeding post-haste to try to find a solution."

The $54 million mission represents the maiden voyage for NASA's so-called Origins Program, which aims to determine how life arose on Earth and if it exists elsewhere in the universe.

The troubled spacecraft is expected to help scientists understand how and when stars and galaxies formed. That information, in turn, would shed light on the processes which lead to the formation of sun-like stars and potentially habitable Earth-like planets.

Detailed studies also are to be made of:

  • "Methane dwarfs," which are thought to be more massive versions of giant gaseous planets like Jupiter.
  • Nearby stars that have cast off chunks of debris that ultimately come together in space to form planets.
  • In addition, the spacecraft is supposed to make the most comprehensive survey ever of the rocky objects that make up the asteroid belt between Mars and Jupiter.

    Perhaps most enticing, however, would be a planned search for powerful quasars that formed shortly after the Big Bang, the primordial explosion scientists think spawned the universe 15 billion years ago.

    The results of that search, scientists say, could yield new clues about the age, structure and fate of the universe.


    JET PROPULSION LABORATORY
    CALIFORNIA INSTITUTE OF TECHNOLOGY
    NATIONAL AERONAUTICS AND SPACE ADMINISTRATION

    March 5, 1999

    PROBLEM REPORTED ON NASA'S WIDE-FIELD INFRARED EXPLORER

    After a successful launch last night from Vandenberg Air Force Base, Calif., NASA's Wide-field Infrared Explorer (WIRE) spacecraft began to experience attitude control problems during its second pass over the ground station at Poker Flat, Alaska.

    It is not yet known specifically what caused the orientation malfunction on the spacecraft and a further investigation, now underway, is being done to assess the problem.

    An aberration was detected during the second pass over the Alaskan station, and confirmed on the third pass. The WIRE launch and science teams are reviewing and assessing the data stream from the spacecraft to try to determine the nature of the problem.

    Further updates will be released as information concerning WIRE's anomaly is obtained.

    The WIRE observatory consists of a three-axis-stabilized spacecraft designed, built and tested by the Small Explorer Project at NASA's Goddard Space Flight Center, Greenbelt, Md., and a cryogenically cooled infrared telescope provided by the Jet Propulsion Laboratory.


    JET PROPULSION LABORATORY
    CALIFORNIA INSTITUTE OF TECHNOLOGY
    NATIONAL AERONAUTICS AND SPACE ADMINISTRATION

    WIDE-FIELD INFRARED EXPLORER LAUNCH STATUS

    March 2, 1999

    The launch of NASA's Wide-Field Infrared Explorer (WIRE) astronomy spacecraft mission from a Pegasus-XL launch vehicle at Vandenberg Air Force Base, Calif., will be rescheduled for no earlier than Thursday, March 4.

    Engineers continue to troubleshoot a mechanism that secures the rudder pin on the Pegasus-XL rocket and the device that retracts the pin for flight. The launch was aborted 45 seconds before the scheduled liftoff time of 6:56 p.m. PST Monday, March 1, when the Pegasus' rudder pin did not retract, preventing steering of the rudder. The rocket, built by Orbital Sciences Corporation, is a three-stage, solid-propellant booster system carried aloft by a Lockheed L-1011 jet aircraft. The system, carrying the 561-pound (254-kg) spacecraft, will be released when the aircraft reaches an altitude of about 40,000 feet (12,200 meters).

    A definite date for a second launch attempt has not been set, but launch now can occur no earlier than Thursday, March 4, when the launch window extends from 6:51:50 to 7:01:50 p.m. PST. The drop of the Pegasus from the L-1011 aircraft is targeted to occur at 6:57 p.m. PST at a location over the Pacific Ocean approximately 150 miles northwest of Vandenberg Air Force Base, CA.

    NASA engineers are continuing with the cyrogenic servicing effort for the WIRE spacecraft. WIRE's telescope is a 30- centimeter (12.5-inch) aperture Cassegrain instrument enclosed in a two-stage, solid-hydrogen thermos-like cryostat, which will keep the instrument's mirrors cooled to below -260 Celsius (-436 F). The telescope must be cold so that its own heat emission doesn't overwhelm the light that it is trying to detect from space.

    The four-month mission will help answer questions about how and when galaxies formed, and the subsequent history of star- formation in the universe. The WIRE spacecraft will be inserted into an orbit with an altitude of 540 kilometers (340 miles) above the Earth, and will orbit every 90 minutes. The mission is managed by NASA's Goddard Space Flight Center, Greenbelt, MD, and the WIRE science operations center is located at the Infrared Processing and Analysis Center (IPAC), California Institute of Technology, Pasadena, CA.

    For more information about the Wide-Field Infrared Explorer, check the web page.


    NASA Headquarters, Washington, DC
    Goddard Space Flight Center, Greenbelt, MD
    Jet Propulsion Laboratory, Pasadena, CA

    February 23, 1999

    WIDE-FIELD INFRARED EXPLORER TO SURVEY STARBURST GALAXIES

    One of NASA's smallest spacecraft will tackle a very big cosmic question: What is the history of star-formation in the Universe?

    NASA's first new spacecraft in the Origins Program, the Wide-Field Infrared Explorer (WIRE), was scheduled for launch at 10 p.m. EST on March 1 from Vandenberg Air Force Base (AFB), CA.

    The four-month mission will help understand how and when galaxies formed, and the subsequent history of star-formation in the Universe. Answers to these questions will shed a strong light on the very nature of the Universe.

    "In many ways this inaugural mission of NASA's Origins Program, which will study the birth of star-forming galaxies, will move us towards our ultimate goals," said Dr. Harley Thronson, acting director of the Astronomical Search for Origins science theme at NASA Headquarters, Washington, DC. "One of the Origins Program's long-term goals is to understand the formation of not only the Universe, but the galaxies and stars we see everywhere in the cosmos. WIRE will provide us with a wealth of information, which will get us closer to understanding how the Universe could reach the point of forming Sun-like stars and Earth-like planets. And, WIRE will do that at a very modest cost."

    "Our science team will measure how densely filled the Universe has been with star-forming galaxies during its history, and how quickly those galaxies have been forming stars," said WIRE Principal Investigator Perry Hacking of Vanguard Research, Inc., Fairfax, VA; NASA's Jet Propulsion Laboratory (JPL), Pasadena, CA; and a professor at El Camino College, Torrance, CA. "WIRE also will conduct a search for powerful, dusty quasars in the very early Universe, shortly after the Big Bang. If found in significant numbers, these quasars will carry strong implications about the age and structure of our Universe."

    Additional WIRE science investigations will include detailed inventories of some star-forming regions in our own Milky Way galaxy; searches for small, substellar objects called 'methane dwarfs,' which are essentially more massive versions of the planet Jupiter; searches of nearby stars for leftover debris from planet formation; a more complete inventory of the asteroid belt, and much more.

    The 561-pound (254-kg) spacecraft will be launched from Vandenberg AFB on a Pegasus-XL launch vehicle built by Orbital Sciences Corporation. The launch vehicle is a three-stage, solid- propellant booster system carried aloft by a Lockheed L-1011 jet aircraft. The system will be released when the aircraft reaches an altitude of about 40,000 feet (12,200 meters).

    The WIRE instrument consists of a 12.5-inch (30-centimeter) aperture Cassegrain telescope with no moving parts and a field of view about the size of the full moon. The telescope is enclosed within a two-stage, state-of-the-art, solid-hydrogen cryostat, which will keep the instrument's mirrors cooled to below -436 F. The cryostat is designed like a thermos bottle, using a vacuum space between layers of insulation, and uses the sublimation (the direct transition from a solid to a gas) of frozen hydrogen to cool the telescope. The telescope must be cold so that its own heat emission doesn't overwhelm the light that it is trying to detect from space.

    The WIRE observatory will be inserted into an orbit with an altitude of 340 miles (540 km) above the Earth, and will orbit the Earth every 90 minutes. The observed data will be stored in the spacecraft memory and sent to ground stations at Poker Flat, AL, and NASA's Wallops Flight Facility, VA. From there the data will be sent to the spacecraft control center at NASA's Goddard Space Flight Center, Greenbelt, MD, and then on to the science operations center at the Infrared Processing and Analysis Center (IPAC), California Institute of Technology, Pasadena, for data calibration and analysis. The WIRE teaming partner is Space Dynamics Laboratory at Utah State University, Logan, UT.

    WIRE is the last of an initial series of Small Explorers (SMEX) that have been designed and built at Goddard. The Small Explorer office has provided the mission, spacecraft, and ground system engineering and the principal investigator has provided the scientific instrumentation for these missions.

    The WIRE observatory was integrated into a three-axis- stabilized spacecraft designed, built, and tested by the SMEX Project Team at Goddard. The telescope assembly is provided to Goddard by JPL. After an initial checkout period of thirty days on orbit, scientific operations will be coordinated by JPL through the science operations center at IPAC.

    The SMEX program provides frequent flight opportunities for highly focused, relatively inexpensive and small space science missions. Each mission is cost-capped for design, development, and operations through the first 30 days in orbit. Using modern technology and management techniques, the program is dedicated to the forty-year Explorer Program tradition of service to the space science community.

    "The Small Explorer program has produced remarkable results," said Jim Watzin, Project Manager for SMEX. The SMEX program already has four spacecraft (SAMPEX, FAST, SWAS and TRACE) successfully operating on-orbit. "All were completed on schedule and within or below the program cost constraints," he said. "All missions differed dramatically from each other in form, function, and scope. WIRE will be the fifth and final mission developed in this manner." Future SMEX missions are to be built at the institution chosen by the principal investigator.

    Additional information:

    WIRE Project website

    WIRE science website


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