Asteroid 2007 WD5 Won’t Hit Mars

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Sorry to disappoint those of you hoping for some Martian fireworks the end of this month. NASA’s Near Earth Object (NEO) Program office has effectively ruled out the possibility of Asteroid 2007 WD5 impacting Mars. The probability of such an event has dropped dramatically, to approximately 0.01% or 1 in 10,000 odds of an impact. Observers also say the asteroid has no possibility of impact with either Mars or Earth anytime in the next century.

Recent tracking measurements of the asteroid from several Earth-based observatories have provided a significant reduction in the uncertainties of the asteroid’s position during its close approach to Mars on Jan. 30, 2008. The best estimates now have 2007 WD5 passing about 26,000 km (16,155 miles) from the planet’s center at approximately 12:00 UTC (4:00 am PST) on Jan. 30th. The NEO office at the Jet Propulsion Laboratory has 99.7% confidence that the pass should be no closer than 4000 km (2,485 miles) from Mars’ surface.

The 50 meter (164 feet) wide asteroid was discovered in late November of 2007 by astronomers at the University of Arizona as part of the Catalina Sky Survey. Other telescopes used to track the asteroid are the Kitt Peak telescope in Arizona, the Sloan Digital Sky Survey telescope in New Mexico, New Mexico Tech’s Magdalena Ridge Observatory, the Multi-Mirror Telescope in Arizona, the Mauna Kea telescope in Hawaii and the Calar Alto Observatory in Spain.

An impact on Mars by 2007 WD5 could have created a .8 km (1/2 mile) wide crater on the planet’s surface. Many scientists were excited by the prospect of such an event, one that could possibly be tracked by the many spacecraft orbiting and on the surface of the red planet.

NASA’s Spaceguard Survey continually searches for Near-Earth Asteroids such as 2007 WD5, and their goal is to discover 90% of those larger than 1 km in size. JPL’s NEO office says that goal should be met within the next few years. Each discovered asteroid is continually monitored for the possibility of impact on Earth.

Original News Source: Near Earth Object Program press release

China Plans for Big Year in Space

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China is hoping to launch 15 rockets, 17 satellites and its third manned mission in 2008. This is an ambitious manifest for any country, and it appears China hopes to take its global emergence to new heights in a year in which it will also host the summer Olympics.

No details were provided regarding specific dates or the types of unmanned missions that will be launched this year. The secretary-general of the Commission of Science Technology and Industry for National Defence, Huang Qiang, revealed the planned launches at a news conference on January 7, according to the official Xinhua news agency.

However, Chinese media reported earlier that the China National Space Administration plans to launch its third manned mission, Shenzhou VII sometime in October, and reportedly the mission will include a space walk. In 2003, China became only the third country to put a human into space using its own rocket, following the former Soviet Union and the United States, and in 2005 the Shenzhou VI rocket sent two Chinese astronauts on a five-day flight.

Xinhua quoted Huang as saying the Shenzhou VII was a major task for the year and called for full cooperation between all departments involved.

China successfully launched its first lunar probe, Chang’e 1 in October 2007. The spacecraft is now successfully in lunar orbit and it returned its first images of the lunar surface in late November 2007. Chang’e 1 is also obtaining 3-D pictures of the moon and mapping surface elements. This was the beginning of their “step by step” program of exploring the moon. China hopes to deploy a lunar lander for surface exploration of the moon in 2012, and attempt a lunar sample return mission in 2017.

China will also mount a joint effort with Russia to explore Mars in 2009.

Original News Source: Reuters

Comet, Cometary Dust Formed in Different Parts of Solar System

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Scientists studying the particles of comet dust brought to Earth by the Stardust spacecraft have uncovered a bit of a mystery. Research on the particles seem to indicate that while the comet formed in the icy fringes of the solar system, the dust appears to have been formed close to the sun and was bombarded by intense radiation before being flung out beyond Neptune and trapped in the comet. The finding opens the question of what was going on in the early life of the solar system to subject the dust to such intense radiation and hurl them hundreds of millions of miles from their birthplace.

The Stardust spacecraft flew to Comet Wild-2 in 2004, coming approximately 150 miles from the comet’s nucleus, and captured particles of dust and gases from the comet’s coma and then returned those particles to Earth in 2006.

Researchers from the University of Minnesota and Nancy University in France analyzed gases locked in the tiny dust grains, which are about a quarter of a billionth of a gram in weight. They were looking for helium and neon, two noble gases that don’t combine chemically with other elements, and therefore would be in the same condition as when the comet dust formed.

The analysis of the helium and neon isotopes suggests that some of the Stardust grains match a special type of carbonaceous material found in meteorites. The gases most likely came from a hot environment exposed to magnetic flares that must have been close to the young sun.

About 10 percent of the mass of Wild 2 is estimated to be from particles transported out from hot inner zones to the cold zone where Wild 2 formed. Earlier research showed that the comet formed in the Kuiper Belt, outside the orbit of Neptune, and only recently entered the inner regions of the solar system.

“Somehow these little high-temperature particles were transported out very early in the life of the solar system,” said Bob Pepin from the University of Minnesota. “The particles probably came from the first million years or even less, of the solar system’s existence.” That would be close to 4.6 billion years ago. If our middle-aged sun were 50 years old, then the particles were born in the first four days of its life.

The studies of cometary dust are part of a larger effort to trace the history of our celestial neighborhood.
“We want to establish what the solar system looked like in the very early stages,” said Pepin. “If we establish the starting conditions, we can tell what happened in between then and now.”

Stardust launched in February 1999, began collecting interstellar dust in 2000 and met up with Wild-2 in January 2004. It’s tennis raquet-sized collector made of an ultra-light material called aerogel, trapped aggregates of fine particles that hit at 13,000 miles per hour and split on impact. It is the first spacecraft to bring cometary dust particles back to Earth.

This study also has relevance in learning about the history of our own planet. “Because some scientists have proposed that comets have contributed these gases to the atmospheres of Earth, Venus and Mars, learning about them in comets would be fascinating,” Pepin said.

The research appears in the Jan. 4 issue of the journal Science

Original News Sources: University of Minnesota Press Release, Lawrence Livermore National Laboratory Press Release

Landing Sites for Mars Science Lab Narrowed to Six

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Where should the next spacecraft land on Mars? The Mars Science Laboratory (MSL) rover is scheduled to launch in the fall of 2009. MSL is a long-range rover that will explore a region on Mars with the goal of determining if Mars has or ever had conditions capable of supporting microbial life. Over fifty landing sites have been proposed by various planetary scientists, and recently, the selection committee narrowed the field down to six possible sites. The final site and a backup will be selected in September of 2008. Here’s a look at the six final candidates:

Mawrth Vallis: Location:Northern Plains, east of Pathfinder rover site (24.65°N, 340.10°E)
Mars Global Surveyor MOLA Instrument
This is an ancient channel carved by catastrophic floods. Spectrometers on the Mars Reconnaissance Orbiter (MRO) have detected clay minerals which contain water, and may also preserve organic materials, so there is great interest in studying these deposits to understand past environments that could have supported life. Images from the MRO HiRise camera show hills with several layers and intriguing boulders.

Nili Fossae Trough: Location: Near Isidis Planitia, and near the Beagle 2 intended landing site. (21°N, 74.2°E)
Nilli Fossae Trough.  Image Credit:  Mars Global Surveyor MOLA Instrument
This region has one of the largest and most diverse exposures of clays minerals that have been detected from orbit. Again, clay minerals contain water, and possibly organic materials. The area is a linear depression about 25 km wide that was created from tectonic activity.

Holden Crater: Location: South of Vallis Marineris (26.4°S, 325.3°E)
Holden Crater.  Image Credit:  Mars Global Surveyor MOLA Instrument
This crater contains deep gullies carved by running water as well as examples of what are assumed to be lake beds and sediments deposited by streams. These deposits are more than three billion years old, which dates back to a wetter period on Mars. Scientists believe Holden Crater once was a lake, and when the water disappeared, wind eroded the surface and formed the ripples and dunes that have been imaged by the HiRise instrument.

Eberswalde Crater: Location: South of Vallis Marineris (23.20°S, 326.75°E)
Eberswalde Delta.  Image Credit:  Mars Global Surveyor MOLA Instrument
The Eberswalde delta is the most convincing evidence on Mars for the persistent flow of a river into a standing body of water. HiRise images show many channels within the delta that have become inverted, which occurs as sediments deposited by flowing water solidify over time and become resistant to erosion. High resolution HiRise images show individual boulders breaking off from the channel deposits.

Miyamoto Crater: Location: Merdiani Planum, near Opportunity Rover site. (1.7°S, 352.4°E)
Miyamato Crater.  Image Credit:  Mars Global Surveyor MOLA Instrument
Located along the western boundary of Meridiani Planum, this 150-km crater has hematite and sulfate-bearing minerals, possibly created from lakes or groundwater. The southwestern part of the crater floor has been stripped by erosion, revealing clay minerals.

Northern Meridiani: Location: Meridiani Planum,2.34°N, 6.69°E
Meridiani.  Image Credit:  Mars Global Surveyor MOLA Instrument
This is the same area that the Opportunity rover has studied. By landing here, the MSL rover could increase our knowledge of the Meridiani region, which Opportunity has revealed to have a complex geologic history that involves flowing water, groundwater, lakes and wind. If chosen as a landing site, the MSL rover would study the smooth plains before driving to the ridged plains to the north.

MSL will arrive on Mars in 2010. Once on the surface, the rover will be able to roll over obstacles up to 75 centimeters (29 inches) high and travel up to 90 meters (295 feet) per hour. On average, the rover is expected to travel about 30 meters (98 feet) per hour, based on power levels, slippage, steepness of the terrain, visibility, and other variables. The science instruments on board include cameras, spectrometers, radiation detectors and environmental sensors.

Original News Source: HiRise Blog

Shuttle Launch Date Still Uncertain

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NASA officials are hoping that the repairs to space shuttle Atlantis’ fuel sensor system will be completed in time for a January 24 launch date for the STS-122 mission to the International Space Station. But in a January 3rd press briefing, John Shannon, deputy manager of the shuttle program told reporters that a February 2nd or 7th launch date is more probable given the testing and the work required.

“There’s no way we’re going to be earlier than Jan. 24,” Shannon said. “I would say it is a stretch to think we would make the 24th, that would require the weather to cooperate out at the Kennedy Space Center, it would require no hitches in any of the testing.”

A suspect connector in the engine cutoff (ECO) fuel sensor system was removed from the shuttle’s external tank and is being tested at the Marshall Space Flight Center in Huntsville, Ala. If the tests there don’t replicate the false readings that occurred during two launch attempts in early December, another on-pad fueling test might be required to collect additional data. If so, the launch could be delayed to Feb. 2 at the earliest.

A fueling test performed on December 18 isolated the problem to the 1 1/2-by-3 inch connector called a pass-through connector, located both inside and outside the tank. The wires for all four ECO sensors pass through the same connector. From the data of that test, engineers believe the problem lies in gaps between pins and sockets on the external side of the pass-through connector when the system is chilled to cryogenic temperatures, as when the tank is filled with liquid hydrogen and oxygen.

“It’s a difficult problem,” Shannon said. “I’m not making excuses here, but at liquid hydrogen temperatures is the only time it shows up so you have to set up a test that uses liquid hydrogen. We’re very interested. This is the first time we’ve removed the hardware from a vehicle and had the opportunity to test it without disturbing it before hand. So it will be interesting to find out.”

Engineers are now working on installing new connectors to the tank.

“All of those changes, it’s fairly simple, it’s a fairly elegant change and we feel very confident that if the problem is where we think it is, between the external connector and the feed through, that this will solve that,” Shannon said. “Now, if you look at the schedule, we’re going to have new external connectors and feed-through assemblies at KSC this weekend and we’re going to proceed with installing that on external tank Number 125, which is the one Atlantis is currently mated to. We expect that work to be done by next Thursday.”

“But I asked the team to go ahead and protect that date (Jan. 24) as the earliest date that we could possibly go,” Shannon continued. “I think it is much more likely that we’ll be ready to go somewhere in the February 2 to February 7 timeframe, given we don’t have any additional findings as we go through our testing.”

Another timing issue to deal with is the scheduled Feb. 7 launch of a Russian Progress supply ship to the ISS. Joint U.S.-Russian space station flight rules don’t allow a Progress docking during a shuttle visit. If the Russians won’t change their launch date, Atlantis would have to take off by Jan. 27 or the flight would slip to sometime around Feb. 9 in order to get the Progress docked before the shuttle arrives.

Also, NASA originally planned to launch the shuttle Endeavour on the next mission to the ISS on Feb. 14. But the Atlantis delay will force a subsequent delay for Endeavour. Shannon said that NASA typically needs five weeks between launches to get ready for the next flight.

Original News Source: NASA News Audio

Former Astronaut John Herrington Resigns from Rocketplane

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Former NASA astronaut John Herrington has resigned from the commercial space company Rocketplane Global, Inc. Herrington left NASA in 2005 to join Rocketplane as vice president and director of flight operations. He was slated to pilot the company’s passenger-carrying suborbital XP spaceplane. His resignation was effective on December 21, 2007.

Herrington said he plans to continue working in the commercial space industry, because he believes “commercial space is the next great adventure in aerospace.” Herrington will also continue as a motivational speaker to both industry and educational institutions, and as an advisor to the University of Colorado’s National Institute for Space, Science and Security Centers. In addition, he’ll also work with the Chickasaw Nation, of which he is a member.

“I was fortunate during my tenure at Rocketplane to work with an incredibly talented group of professionals,” said Herrington. “My decision to leave was a difficult one.”

Rocketplane has had its troubles recently, with several top officials leaving the company, including former company president Randy Brinkley.

But in an interview with me in October, Herrington was optimistic about Rocketplane’s future. “If we can be successful, then hopefully we can make spaceflight more routine, then more people can experience what a unique environment it is,” he said. “And if we can be successful doing both then we provide a market to the consumer that’s looking for high adventure.”

Rocketplane’s company structure consists of the parent corporation Rocketplane Limited, under which are two separate entities: Rocketplane Kistler which is developing a reusable two-stage orbital unmanned spacecraft called the K-1 while Rocketplane Global is building the XP.

In August 2006 Rocketplane Kistler (RpK) won a contract with NASA for the COTS (Commercial Orbital Transportation Services) program, to bring cargo and eventually crew to the ISS. But in October of 2007, NASA terminated its agreement with RpK, citing the company’s failure to meet financial and design review milestones per the agreement. Rocketplane had threatened to sue NASA over the termination of the contract, but several sources now indicate that the commercial space company will not file a lawsuit against NASA.

Herrington said that while working at both NASA and Rocketplane was a dream come true, he spent a lot of time away from home, which took a toll on his family. “There’s an aura associated with being an astronaut, but the reality is that it’s a lot of hard work,” he said. “When the thrill wears off, you stick your head in the books and you spend a lot of time learning what you need to know and then performing in a hostile environment. But it was a dream I had as a kid, and when you fulfill a dream like that it’s a phenomenal feeling.”

Original News Source: Chickasaw Nation Press Release, interview with John Herringon.

White Dwarf or Pulsar?

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A group of astronomers have discovered something they never expected to find. The scientists were studying white dwarf stars, hoping to learn if white dwarfs could be responsible for the cosmic rays that zip through our galaxy and occasionally strike earth. But instead, what they found was that a certain white dwarf star known as AE Aquarii acts like a Pulsar, challenging our understanding of white dwarfs.

Astronomers had believed white dwarfs were inert stellar corpses that slowly cool and fade away, but this recently observed white dwarf star emits pulses of high-energy X-rays as it whirls around on its axis.

A group of astronomers from the US and Japan used the Suzaku X-Ray Observatory, a JAXA and NASA telescope in Earth orbit to make the new observations.

“AE Aquarii seems to be a white dwarf equivalent of a pulsar,” says Yukikatsu Terada, from the Institute of Physical and Chemical Research in Wako, Japan. “Since pulsars are known to be sources of cosmic rays, this means that white dwarfs should be quiet but numerous particle accelerators, contributing many of the low-energy cosmic rays in our galaxy.”

Some white dwarfs, including AE Aquarii, spin very rapidly and have magnetic fields millions of times stronger than Earth’s. These characteristics give them the energy to generate cosmic rays. But the Suzaku observatory also detected sharp pulses of hard X-rays. After analyzing the data, the astronomy team realized that the hard X-ray pulses match the white dwarf’s spin period of once every 33 seconds.

The hard X-ray pulsations are very similar to those of the pulsar in the center of the Crab Nebula. In both objects, the pulses appear like a lighthouse beam, and a rotating magnetic field is thought to be controlling the beam. Astronomers think that the extremely powerful magnetic fields are trapping charged particles and then flinging them outward at near-light speed. When the particles interact with the magnetic field, they radiate X-rays.

“We’re seeing behavior like the pulsar in the Crab Nebula, but we’re seeing it in a white dwarf,” says Koji Mukai of NASA Goddard Space Flight Center in Greenbelt, Md. The Crab Nebula is the shattered remnant of a massive star that ended its life in a supernova explosion. “This is the first time such pulsar-like behavior has ever been observed in a white dwarf.”

Original News Source: NASA/Goddard Spaceflight Center Press Release

SETI@home Needs You!

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If your New Year’s resolutions include trying something new, expanding your horizons, or doing something to benefit humanity, this is for you: SETI@home needs more volunteers to help crunch data in the search for extraterrestrial intelligence (SETI). And the easy part is that your desktop computer does all the work.

SETI uses radio telescopes to listen for narrow band-width radio signals from space. Since these signals don’t occur naturally, a detection of such a signal would indicate technology from an extraterrestrial source.

The SETI project at the University of California-Berkley gets data from world’s largest radio telescope in Arecibo, Puerto Rico, which has recently been updated with seven new and more sensitive receivers. The improved frequency coverage for the telescope is now generating 500 times more data for the SETI project than before, and more volunteers are needed to handle the increase in data.

According to project scientist Eric Korpela, the new data amounts to 300 gigabytes per day, or 100 terabytes (100,000 gigabytes) per year, about the amount of data stored in the U.S. Library of Congress. “That’s why we need all the volunteers,” he said. “Everyone has a chance to be part of the largest public participation science project in history.”

The SETI@home premise is simple but brilliant: Instead of using a monstrously huge and expensive supercomputer to analyze all the data, it uses lots of small computers, all working simultaneously on different parts of the analysis. Participants download a special screensaver for their home computers, and when the computer is idle, the screensaver kicks in to grab data from UC Berkley, analyze the data and send back a report. SETI@home was launched in May of 1999.

The SETI@home software has now been upgraded to deal with all the new data generated by the updated Arecibo telescope. The telescope can now record radio signals from seven regions of the sky simultaneously instead of just one. It also has greater sensitivity and 40 times more frequency coverage.

So, if the phrase “to search out new life and new civilizations” inspires you, her’s your chance to be part of the largest community of dedicated users of any internet computing project. Currently SETI@home has 170,000 individuals donating time on 320,000 computers.

“Earthlings are just getting started looking at the frequencies in the sky; we’re looking only at the cosmically brightest sources, hoping we are scanning the right radio channels,” said project chief scientist Dan Werthimer. “The good news is, we’re entering an era when we will be able to scan billions of channels. Arecibo is now optimized for this kind of search, so if there are signals out there, we or our volunteers will find them.”

Check out SETI@home here.
Original News Source: UC Berkley Press Release

Controversial NASA Aviation Report Released

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NASA released the results on Dec. 31 from an $11.3 million federal air safety study. The agency previously withheld the report, and came under fire from Congress and news organizations for doing so. Earlier reports said NASA was concerned the data in the report would upset travelers and hurt airline profits. But today NASA administrator Mike Griffin and the head of NASA’s Office of Safety and Mission Assurance Bryan O’Connor said the release of the report was delayed to protect both pilot confidentiality and classified commercial aviation information.

“We came across instances in looking at the raw data where information was contained that could have compromised one of those two things,” said Administrator Griffin. “We determined that an independent review of that data was necessary in order to prevent such compromise.”

A panel led by O’Connor reviewed the 16,000 page report and data such as pilots’ names and other confidential information was redacted.

Also, Griffin said there are questions as to the validity of the data in the report, which has not been peer-reviewed.

“We consider the study was not properly organized and not properly reviewed, and that makes the results very difficult to interpret and to use,” he said. The study was conducted by the Battelle Memorial Institute for NASA.

An independent review of the data will be done in the future by the National Academy of Sciences.

Griffin said the original press release highlighting the refusal to release the data used “inappropriate language” to explain the rationale for not releasing the report.

NASA’s survey, the National Aviation Operations Monitoring System (NAOMS), interviewed about 8,000 pilots per year from 2001 until the end of 2004. The program was terminated before moving on to interview flight attendants and air traffic controllers, as originally proposed.

Approximately one million dollars a year was put into this study. Griffin said it is a small fraction of NASA’s overall work, and in retrospect, the study did not receive the attention that it should have.

The report can be found on NASA’s website. Its length makes it difficult to wade through the data. Additionally, some portions of the report that have not yet been edited for confidential information have been left out. NASA will release the remainder of the report as soon as possible.

The original plan for the survey never called for NASA to interpret and analyze the data. The study’s purpose was to develop new methodologies for collecting aviation safety data, and then the data would be transitioned to the aviation safety community.

“NASA conducts research, and this was one element of such research,” said Griffin. “NASA extended the research, which was originally to be concluded in 2004 in order to properly fund the transition of the data and its review. We’ve gone the extra mile with this data and we’ve gone well beyond our original intentions, which is why we’ve brought it to an end.”

It remains uncertain whether any data from the report will ever be used by the aviation safety community. Griffin said it was his understanding that the FAA has “simply moved on from NAOMS,� and that the FAA has over 150 different programs to provide survey data from individuals involved in all areas of air flight.

While NASA didn’t analyze the data, Griffin offered his opinion of what the report surmises: “What the flying public should understand is that they have approximately the same risk of dying from a lightning strike as they do dying from an air transport accident in the United States, which means to say that this is one of the safest forms of travel that human beings have ever invented, and that no one should think otherwise.”

In testimony to Congress earlier this year, Griffin characterized the data in the report as not as valid as he would prefer to have for a NASA report. Griffin said that he still feels that way, and that his concern is that this research work was not properly peer reviewed and the data that was extracted from the survey was not properly vailidated at its conclusion.

The survey purportedly unearthed approximately four times as many engine failures than the FAA has documentation for. “It calls into question the reporting mechanisms rather than the underlying rate of engine failures, which we believe we understand,� Griffin said, adding there are other inconsistencies, as well. “Those kinds of inconsistencies, when we looked at the data, gave us pause for thought, and still do.�

“The value of this will need to be determined by the larger aviation community, which I remind you, does not reside within NASA,” Griffin continued. “All that we at NASA have said is that this survey was not peer reviewed and the data was not validated at its conclusion. It’s up to others whether or not they believe this research has value.”

Griffin had promised to release the report before the end of 2007, and he did so without compromising confidential information that, by law, NASA is prohibited from releasing.

Griffin said this survey doesn’t cast any doubt in his mind about the safety of aviation in the United States. “I did not, having looked at a snapshot of the data, see anything that the flying public would care about or ought to care about,” he said. “But it’s not for me to prescribe what others may care about. We were asked to release the data and we did that.”

The report can be found on the NASA website.

Original News Source: NASA News Audio

STS-122 Shuttle Launch Decision on Tap

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NASA engineers continue to repair a faulty electrical connector on Space Shuttle Atlantis’ external fuel tank which has delayed the launch of the STS-122 mission to the International Space Station. An update of the progress on that work will be presented at a mission management team meeting scheduled for Thursday, January 3 and mission managers will perhaps then be prepared to announce a proposed launch date for Atlantis.

The repairs could take several days or even weeks. At a press briefing last week, shuttle program manager Wayne Hale declined to offer a probable launch date. “We’re in the middle of troubleshooting and repair,” he said. “Until that gets a little bit further along, I actually have no valid dates to give you. To avoid what I think would be a totally misleading headline along the lines of ‘NASA Delays the Space Shuttle Again,’ we’re just not going to give you a launch date because that, in fact, would not be accurate.”

The engine cutoff (ECO) fuel sensor system transmitted false readings during two launch countdowns for Atlantis earlier in December. A fueling test performed on December 18 isolated the problem to a 1 ½ -by 3 inch connector called a pass-through connector, located both inside and outside the tank. The wires for all four ECO sensors pass through the same connector. From the data of that test, engineers believe the problem lies in gaps between pins and sockets on the external side of the pass-through connector when the system is chilled to cryogenic temperatures, as when the tank is filled with liquid hydrogen and oxygen.

Engineers have removed the connector and are bench-testing the components in similar cryogenic conditions to try to duplicate the failure. Meanwhile, new hardware is being installed on the tank as the shuttle sits on launchpad 39A at the Kennedy Space Center.

“We have allowed the team that did the troubleshooting to very thoroughly go through all the data,” said Hale. “They have told us they are sure the problems that we’re seeing reside in that series of connectors. Where exactly in that series of connectors is a little bit open to interpretation.”

The connectors on the inside of the tank are being visually inspected. “It is a possibility that the internal connector is involved,” Hale said. “However, all the physics based discussion of the kinds of things that can happen point to something happening on the external connector.”

Problems with the internal connector would involve “more invasive” work, Hale said, that could possibly damage the tank.

A similar repair was done to the Atlas rockets several years ago to fix problems with circuitry in the Centaur stage. ECO sensors protect the shuttle’s main engines by triggering engine shut down if fuel runs unexpectedly low. The Space shuttle main engines running without fuel would likely result in an explosion.

The STS-112 mission will deliver the European Space Agency’s Columbus science module to the station along with a new crew member Leopold Eyharts from France who will take over for Dan Tani. Tani, whose mother was killed in a car accident on December 19, will return to Earth on Atlantis.

“These repairs and troubleshooting activities will determine when we will launch” said Hale. “The plan to go forward will take as long as it takes, but we don’t think this will be a long-term thing. Probably something that will take a couple of weeks.”