Posted on by Nancy Atkinson

Day of Troubleshooting Leads to Clues for Shuttle and ISS

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Tuesday, December 18 was a day of major troubleshooting for NASA, as the space agency tries to hunt down the causes of problems plaguing both the shuttle and the International Space Station. While the day ended with few definitive answers, NASA officials said the data they gathered — and even what they didn’t find — will help them make strides towards solving the issues.

A tanking test on the shuttle’s external fuel tank helped narrow down a problem with the engine cutoff sensors to a “pass-through” connector in the system, but shuttle program manager Wayne Hale said the exact problem is not yet known.

“Exactly what we’ve got to do and where in this three-part connector we have to do it is a little bit of work ahead of us,” he said. “I’m just pleased as punch we know it’s in the connector and not some other place in the 100 feet or so of wiring and sensors and electronic boxes so we know what area to concentrate our efforts.”

But how much work the fix will entail, or how the repairs might affect the proposed January 10 launch date is also in question.

“I do not have any information about a launch date today,” Hale said. “Where the troubleshooting and replacement and repair work leads us will determine what the launch date’s going to be. We are not going to be driven by schedule on this one. We need to get to the bottom of this, fix it and make sure it’s fixed once and for all and then we can fly safely through the rest of the program, at least in this area.”

However, Hale said he felt the problems could be turned around in fairly short order.
He said the problem appears to be temperature related, or perhaps related to the tightly sealed, almost vacuum like conditions the connector operates in.

The 1 1/2-by-3 inch connector is called a pass-through connector because it is located both inside and outside the tank. The part that will be difficult to get to is the socket connector on the inside of the tank. Engineers would have to go inside the ET through a “man-hole cover” in the bottom of the tank, and that would entail a longer time to fix the problem.

Engineers are still troubleshooting some issues in bench tests away from the shuttle, and more data will be presented to program managers on Wednesday.

Meanwhile, two ISS astronauts conducted a seven hour spacewalk on Tuesday, inspecting problems with two unrelated mechanisms that allow the station’s solar wings to track the sun for power. It was the 100th EVA in support of station construction and maintenence.

Station commander Peggy Whitson and flight engineer Dan Tani first looked at a malfunctioning beta gimbal assembly that tilts the the starboard solar arrays to face the sun. Engineers thought that perhaps a micrometeoroid hit may have damaged the device, but the astronauts found no evidence of any impacts. The spacewalkers temporarily disconnected cables and a subsequent test found that the motor most likely is the problem. A new motor will be installed during the next shuttle mission.

The issues with the solar array rotary joint, a huge mechanism that also automatically rotates the solar arrays to face the sun, will require more work, contemplation and likely several spacewalks to fix. No “smoking gun” was found as to what is causing the joint to vibrate and display electrical spikes. In addition, metal shavings were found during an earlier inspection of the SARJ. Space station program manager Mike Suffredini said repairs probably won’t begin until next fall after a station crew can be trained to repair the joint. The shuttle crews “to-do” lists are already filled for the remaining shuttle flights in order to finish the construction of the ISS.

Mike Suffredini said the station team is “challenged” by the issues they are facing in the two repairs.

“The fact that it (the SARJ) looked as we expected is an enormous amount of information for us,” said Sufradini. “It would be really nice if something stood out and said ‘hey, I’m the cause of your problem,’ but we didn’t get that.”

Original News Source: NASA TV

Posted on by Nancy Atkinson

Enceladus: Cold Moon With a Hot Spot

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Geysers spew from Enceladus in this image from the Cassini spacecraft. Credit: NASA/Cassini mission.

Saturn’s tiny moon Enceladus is a cold and icy place. But somehow, there’s enough heat being generated on Enceladus’ south pole to eject plumes of ice and vapor high above the moon. These plumes are extremely intriguing to the Cassini mission scientists and they want to know more about this hot spot on a very cold moon. In fact, Enceladus has become a major priority for study by the Cassini team and they are anticipating learning more about the moon in an upcoming fly-by.

The temperature at Enceladus’ south pole is about -220 degrees Celsius, but the hot spot is at least 100 degrees warmer. The leading model for the cause of the plumes on Enceladus is that the moon’s tides cause its crust to ratchet, or rub back and forth, in a set of faults near the south pole. The forces between Enceladus, the big planet Saturn and another moon, Dione cause what’s called dynamical resonance, and Enceladus is continually squeezed under this gravity field. This process creates a small hot spot, in relative terms, for an icy satellite.

Cassini has actually flown through the plumes, giving scientists a glimpse of the plume’s make-up.

“The plume particles are like smoke, ice smoke,”said William B. McKinnon, professor of earth and planetary sciences at Washington University in St. Louis. “If you were standing on Enceladus’ surface you wouldn’t even be able to see the plumes. The particles are just larger than the wavelength of light, about one-thousandths of a millimeter. Most icy bodies of this size are geologically inert, but this is a clear indication of geological activity. Cassini has found active venting of water vapor. This leads to scientifically intriguing speculations and questions.”

The scientists are pondering if Enceladus has active ice volcanism, and if so, is it due to ice sublimating, like a comet, or due to a different mechanism, like boiling water as in Old Faithful at Yellowstone. Even though there may be water on the moon, McKinnon doesn’t believe there is the possibility of life on Enceladus. This is because measurements made from Earth don’t indicate there is enough sodium present in the plumes to warrant the “life” question.

“The emerging view is that there’s not obvious evidence for a subterranean ocean in contact with rock, no boiling or venting,” said McKinnon.

The Cassini science team has made Enceladus a major priority and there will be seven additional close fly-bys of the moon by the spacecraft through mid-2010 (provided the mission is extended to that period.) The next fly-by will be on March 8, 2008 and Cassini will approach Enceladus at an incredibly close 25 km in altitude at the low latitudes and fly over the south pole at 580 km altitude. The spacecraft will actually fly through the plumes and should be able to take high-phase images of the plumes, map the temperatures of that region, search for any activity at other latitudes as well as image other interesting features on Enceladus, such as “tiger-stripe”-like fissures found near the south pole.

“We still can’t say how truly ‘hot’ the hot spots are,” said McKinnon. “We’ll probably learn this in March.”

Original News Source: Washington University Press Release

Posted on by Nancy Atkinson

Heavy Construction on the Moon

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Take a look at any construction project or surface mining operation here on Earth and likely there will be bulldozers, loaders, and trucks; all essential in excavating and building structures. But as we look to the future with NASA’s Vision for Space Exploration which calls for a return to the Moon to build bases and habitats, how will heavy construction and excavation be accomplished on the lunar surface?

Caterpillar Inc., a company known for their heavy earth moving machines and the world’s leading manufacturer of construction and mining equipment, is looking to tackle that issue. They’ve partnered with NASA to create technology that could benefit construction and mine workers everywhere in the future, whether they grab a hard-hat or a space helmet on their way to work.

Caterpillar was one of 38 companies awarded seed funds as part of NASA’s Innovative Partnerships Program (IPP). Projects are selected for this program because of their potential to advance key technologies that will help meet NASA’s critical needs for the future.

Caterpillar has proposed a multi-terrain loader for lunar surface development. Currently, they are working with NASA to develop the technology to augment existing earth moving equipment with sensors and on-board processors to provide time-delayed tele-operational control.

The loader would be able to undertake regolith moving such as grading, leveling, trenching, strip-mining, excavating and habitat covering. It also could be used for construction of lunar bases, the deployment or relocation of surface assets, as well as for mobility on the Moon.

Why is a down-to-earth company like Caterpillar interested in the Moon?

“The way we looked it, there are technologies that are needed on both the Earth and the moon,” Michele Blubaugh, Manager of Intelligence Technology Services at Caterpillar, told Universe Today. “We looked at autonomous operations of equipment as being the same type of technology that could be used on the moon as well as in a mining application. We have the same end result as NASA.”

That end result is to remove operators of construction equipment from a dangerous situation, whether it’s a machine operator in a dangerous mine environment or whether the operator is an astronaut on the lunar surface trying to excavate habitat sites.

There are two types of tele-operation. One is remote operation, where control of the machine is done with a remote operating system. There would be either a vision system on board or someone could actually see the machine as its operating. The other is autonomous operation, where the desired work is programmed and offloaded onto the machine and then the machine carries out the work without anyone interfacing with the machine, either remotely or directly. The machine would read the program at the site, positions itself, have avoidance capabilities to avoid rocks or any object that might be in the way, operating on its own to complete the given mission.

Caterpillar is working on both types of operation. “It’s one step to the next,” said Blublaugh. “You need both of those technologies developed, with remote operations first, and then the ultimate is autonomous operations.”

They are also investigating working remotely or autonomously on the Moon from Earth, and dealing with the six second time delay between the earth and the moon.

Caterpillar 287 C Skid Steer Loader. Image Credit: Caterpillar, Inc.
Currently, there are two multi-terrain loaders, the Caterpillar 287 C Skid Steer loader, outfitted with duplicates of the remote technology. One is located at Caterpillar’s proving grounds near their headquarters in Peoria, Illinois and the other is at the rock yard at Johnson Space Center in Houston, Texas. “That way we can develop it together,” said Blubaugh. “When we’re doing something, we each have a machine so we know how something reacts.”

The technology is still in the development stage. “We did some initial basic demonstrations when we delivered the machine in May of 2007 at JSC,” Blubaugh said. “A group of us went down, and the people at JSC were taught to use the machine and what the capabilities were, and we discussed the interfaces between the different types of technology.” In the summer of 2008, the group from Caterpillar will return to JSC to do an interim demonstration at a desert site.

Both machines have been undergoing tests. “Within the contract, NASA is responsible for some of the development and Caterpillar is responsible for other portions,” said Blubaugh, “and then there are things that we do jointly to move the technology along faster, so everyone benefits. JSC gets benefits of our facilities and our engineers working on technology, and vice versa, CAT gets benefits from the folks working at JSC and the technology they have and their facilities, so it’s a mutually beneficial relationship between Johnson and CAT.”

Caterpillar has another contract proposal going to JSC shortly that takes the project to the next level.

“We’ll look to do berming, which is building an earthen berm around a site, leveling and sensing the position of the blade,” said Blubaugh. “We take the technology that we have accomplished today and take it to the next level. It’s almost an annual step by step process in the development and our target date for having a signature demo showcasing this type of technology autonomy, being able to load a program into the machine and having it operate all by itself is targeted for 2012.”

Since the 287 C skid loader is extremely heavy and runs on a diesel engine, it couldn’t be used on the moon. A prototype of a lunar loader-type vehicle is being developed by NASA and Caterpillar is assisting with developing the blade. “So, we’ll be involved in the project all the way along as it develops,” said Blubaugh.

The one-year IPP projects involve collaboration between NASA and a company from the private sector, academia or another government laboratory. All IPP companies address technology barriers with cost-shared, joint-development programs.

Other examples of NASA IPP research areas include the pursuit of improved engine performance and reduced emissions for aeronautics research; high-temperature materials for lunar lander engines, optics to lower error rates of future space telescopes, and a glass bubble insulation demonstration for cryogenic tanks.

With a total cost of the Caterpillar project of just under $1,000,000, Caterpillar is estimated to contribute about 45% and NASA 55%. For the entire NASA’s Innovative Partnership Program $9 million in funding comes from NASA’s Technology Transfer Partnerships budget, $13 million is provided by NASA sources in programs, projects, or field centers, and $12 million from external partners for a total combined financial commitment of $34 million.

“A lot of us at Caterpillar grew up in the time of the first space development,” said Blubaugh, “it’s quite exciting for us to be a part of this. Plus, it’s just a good investment in the future.”

Posted on by Nancy Atkinson

Happy Holidays in Space

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NASA is encouraging Earthlings to send a holiday greeting to the members of Expedition 16 on board the International Space Station. NASA’s Homepage contains a link to send your holiday good wishes to the crew with pre-made e-postcards. The sentiment is nice, however the cards seem a little backwards.

One e-card has a picture of the ISS with a caption that says “The View From 220 Miles Up,” while another displays a waving EVA astronaut saying “Wish You Were Here.” These cards are supposed to be to the crew and from Earth, so perhaps more appropriate might be a picture of a snowy holiday scene or a majestic Earth landscape with the caption “Wish You Were Here, But Glad You Are Up There Furthering the Advances of Human Spaceflight.”

But take this opportunity to express yourself to the ISS crew.

And now on to more pressing news from the ISS:

Space shuttle Atlantis’ STS-122 mission to the space station has now been delayed to no earlier than January 10, 2008.

“Moving the next launch attempt of Atlantis to Jan. 10 will allow as many people as possible to have time with family and friends at the time of year when it means the most,” said shuttle Program Manager Wayne Hale. “A lot has been asked of them this year and a lot will be asked of them in 2008.”

Additionally, it gives engineers more time to understand the engine cutoff sensor problem that has kept the shuttle on the ground. An original launch of Dec. 6 was scrubbed when the sensors failed in a routine test during fueling of the shuttle’s external tank. The problem re-occurred in subsequent tanking test during countdown on Dec. 9, which caused NASA officials to decide to delay the launch until after the first of the year.

STS-122 will bring the Columbus science module to the station, the European Space Agency’s major contribution to the ISS. In addition to conducting three spacewalks to outfit the new science module, shuttle astronauts would also have done a fourth EVA to inspect a troublesome solar array rotary joint on the ISS’s power-providing solar panels that is contaminated with metallic shavings.

So instead ISS astronauts Peggy Whitson and Dan Tani will do that inspection on a spacewalk on Tuesday, December 18 starting at 6:00am EST. They will also look at another more recent power system problem that could be the result of a micrometeoroid or debris impact. On Dec. 8, two circuit breakers tripped, possibly the result of a space debris impact that might have damaged the mechanism that allows power and data to flow through the rotary joint used to turn the array about its axis.

For the SARJ problem, the starboard SARJ is locked in place because of excessive vibration and the metallic shavings and “bearing race ring” damage that were discovered during a quick inspection during the last shuttle mission. The SARJ has two drive gears and two redundant drive motors.

Whitson and Tani could install new bearings on the undamaged race ring and reposition the motors. The other option is to clean up the contamination and fix whatever is causing the problem.

“Once they have more data, they can make a better assessment of which of those approaches we should do, whether we should clean up the current race ring or just shift over,” ISS Commander Peggy Whitson said in a news conference from the station on Thursday morning. “I think either one’s doable,” she continued. “To me, in my mind, I think it would be probably, from an astronaut’s perspective, easier to just shift to the other race ring rather than trying to clean it up. But we don’t know yet how easy that’s going to be to clean up.”

Kirk Shireman, deputy manager of the space station program at the Johnson Space Center, said in a later news conference that no decisions will be made until engineers have more information about what might be causing the problem. The port-side solar arrays and that SARJ is operating normally.

“The idea is, we’ll conduct the EVA right now, the SARJ inspection and the BGA inspection, and we’ll learn what we need to learn,” Shireman said. “Then we’ll find the most opportune time to go fix it, not only the BGA but hopefully the SARJ. It really depends on how our analysis comes out. We’ll figure out exactly how long we can go with the BGA locked and the SARJ restrictions we have in place.”

Back to some holiday frivolity, since Tani would have returned to Earth with the STS-122 crew, which was originally scheduled to return home around the 19th of December, he wasn’t supposed to be on board the ISS during Christmas. Reporters inquired about his change of holiday plans and how gift arrangements were being handled. When asked, Commander Whitson declined to answer if all Tani would be receiving from her would be a lump of coal, saying she didn’t want to give away the surprise.

The astronauts said they have been hoarding foods like smoked turkey and other holiday-type goodies, saving them for Christmas dinner, so it appears that Atlantis and STS-122 were supposed to deliver the holiday meal. However a Progress re-supply ship will be docking with the ISS on Christmas Day, and one of the first things to be unpacked are hamburgers and fresh tomatoes and lettuce. Since fresh foods are a rare commodity on board the station, an All-American burger will be a welcome holiday treat for the crew.

Expedition 16 has also recorded a holiday message to Earth. Watch it here

Original News Source: NASA Press Release, NASA TV

Posted on by Nancy Atkinson

The Spirit Rover’s Big Discovery

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Amazingly, the two Mars rovers, Spirit and Opportunity, have been working diligently on the surface of the Red Planet for almost four years now. So far, Opportunity has grabbed most of the spotlight, finding evidence for past water on Mars within months after landing on the smooth plains of Meridiani Planum. While Spirit has been working just as hard, if not harder, climbing hills and traversing the rocky terrain of Gusev Crater, she hasn’t yet caused quite the stir that her twin has. But now, a recent discovery by Spirit at an area called Home Plate has researchers puzzling over a possible habitat for past microbial organisms.

What Spirit found is a patch of nearly pure silica, a main ingredient in window glass.

“This concentration of silica is probably the most significant discovery by Spirit for revealing a habitable niche that existed on Mars in the past,” said Steve Squyres, principal investigator for the rovers’ science payload.

The silica could have been produced from either a hot-spring type of environment or another type of environment called a fumarole, where acidic steam rises through cracks in the planet’s surface. On Earth, both of these types of environments teem with microbial life.

“The evidence is pointing most strongly toward fumarolic conditions, like you might see in Hawaii and in Iceland,” said Squyres. “Compared with deposits formed at hot springs, we know less about how well fumarolic deposits can preserve microbial fossils. That’s something needing more study here on Earth.”

Squyres said the patch that Spirit has been studying is more than 90 percent silica, and that there aren’t many ways to explain such a high concentration. One way is to selectively remove silica from the native volcanic rocks and concentrate it in the deposits Spirit found. Hot springs can do that, dissolving silica at high heat and then dropping it out of solution as the water cools. Another way is to selectively remove almost everything else and leave the silica behind. Acidic steam at fumaroles can do that. Scientists are still assessing both possible origins.

One reason Squyres favors the fumarole story is that the silica-rich soil on Mars has an enhanced level of titanium. On Earth, titanium levels are relatively high in some fumarolic deposits.

Meanwhile both rovers are hunkering down for another winter season on Mars. Spirit’s solar panels are currently coated with dust from the huge dust storm the rovers endured this summer, and Spirit will need to conserve energy in order to survive the low light levels during the winter.

“The last Martian winter, we didn’t move Spirit for about seven months,” said John Callas, project manager for the rovers. “This time, the rover is likely to be stationary longer and with significantly lower available energy each Martian day.”

I’m keeping my fingers crossed for another solar panel cleaning windstorm event, which has happened previously, giving the rovers a boost in power.

Original News Source: Jet Propulsion Laboratory News Release

Posted on by Nancy Atkinson

Building Blocks of Life Can Form on Cold, Rocky Planets — Anywhere

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Our old friend and headline-maker is back in the news. Meteorite ALH84001 — the Mars rock that sent the world of astrobiology into a tizzy back in 1996 — hasn’t been just sitting around collecting dust. Researchers have been re-examining the famous meteorite in an effort to learn more about the early history of Mars. Not only did ALH84001 help determine that the building blocks of life actually did form on early Mars, but also that those same building blocks have the potential to form on a cold rocky planet anywhere in the Universe.

The meteorite, found in the Alan Hills region of Antarctica, grabbed the headlines over 11 years ago when scientists claimed to have found the remains of bacteria-like life forms within the rock from Mars. The claims have been hotly debated, with both sides still holding firm in their convictions.

But scientists at the Carnegie Institution’s Geophysical Laboratory took the research into ALH84001 a step further, and have shown for the first time that building blocks of life formed on Mars early in its history. Organic compounds that contain carbon and hydrogen form the building blocks of all life here on Earth. Previously, some scientists thought that organic material in ALH84001 was brought to Mars by meteorite impacts, and others felt the material might have originated from ancient Martian microbes, while still others thought any organics in the rock probably were introduced after it arrived on Earth.

The Carnegie-led team made a comprehensive study of the ALH 84001 meteorite and compared the results with data from related rocks found on Svalbard, Norway. The Svalbard samples came from volcanoes that erupted in a freezing Arctic climate about 1 million years ago — possibly mimicking conditions on early Mars.

“Organic material occurs within tiny spheres of carbonate minerals in both the Martian and Earth rocks,â€? said Andrew Steele, lead author of the study. “We found that the organic material is closely associated with the iron oxide mineral magnetite, which is the key to understanding how these compounds formed.”

“The results of this study show that volcanic activity in a freezing climate can produce organic compounds,” said Hans E.F. Amundsen, a co-author in the study from Earth and Planetary Exploration Services. “This implies that building blocks of life can form on cold rocky planets throughout the Universe.”

The organic material in the Allan Hills meteorite may have formed during two different events. The first, similar to the Svalbard samples, was during rapid cooling of fluids on Mars. A second event produced organic material from carbonate minerals during impact ejection of ALH84001 from Mars.

“Our finding sets the stage for the Mars Science Laboratory (MSL) mission in 2009,” said Steele, who is a member of the Sample Analysis on Mars (SAM) instrument team onboard MSL. “We now know that Mars can produce organic compounds. Part of the mission’s goal is to identify organic compounds, their sources, and to detect molecules relevant to life. We know that they are there. We just have to find them.”

This makes the MSL mission all the more exciting and anticipated. And perhaps the team of scientists who made the claims about microbes in ALH 84001 back in 1996 have something to strengthen their case.

Original News Source: Carnegie Institution For Science Press Release

Posted on by Nancy Atkinson

Water or Land: The Orion Landing Choice

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Work is progressing on designing the new Orion Crew Exploration Vehicle (CEV), the next generation of NASA spacecraft that will take humans to the International Space Station, back to the Moon, and hopefully on to Mars. But one major question about the spacecraft has yet to be answered. On returning to Earth, will the CEV splash down in water, or land on terra firma?

NASA officials discussed various aspects of development that is currently underway for the Constellation program at a media briefing on December 10. The mobile launch platform for the Ares rocket is being built, landing parachutes have been tested and the first capsule structure of the new CEV will be constructed starting in early 2008. Design requirements for the booster rockets have been completed and just ahead are final design definitions for operational capabilities such as ground procedures at Kennedy Space Center, mission control in Houston and other areas such as spacesuit design.

Additionally research on the International Space Station has begun to help prepare for long duration spaceflights such as a measurements of microbe growth, a study of the formation of kidney stones, and a nutritional study to help understand what is “normal” for the human body in space.

But questions from the media focused mainly on the yet unmade decision of whether the CEV will land in the water or on land.

NASA originally explored multiple options for landing in both water and land. After initial studies, the first assessment by NASA and the contractor for the CEV, Lockheed Martin, was that landing on land was preferred in terms of total life cycle costs for the vehicles. But now a splashdown in water seems to be favored.

“There are a couple of aspects that pop out at us,” said Jeff Hanley, Manager for the Constellation Program. “One is the safety and the risks involved in landing. Looking at the landing itself, the event of actually touching down, water comes out to be preferable as less risk. Another aspect is the performance of the Orion vehicle as it is sent to the moon. In looking at what it takes to get a pound of spacecraft to low lunar orbit in terms of the cost, every pound that you send toward the moon is precious. From an efficiency and performance point of view, carrying 1500 lbs of landing bags to the moon and back when we have a perfectly viable mode of landing in the water near a US coastal site didn’t seem like a good trade in performance. We’ve tended toward updating our point of departure concept to now be a nominal US coastal water landing.”

The Constellation program has always considered that for the first few missions, the spacecraft would land in water until the guidance system had been tested thoroughly and proven in actual landings.

But NASA is continuing to look at landing on land as a possibility for future flights. “We want to be able to land on land in a contingency and have the crew be able to get out and walk away. Ther are limitation of what you can do on land but by the time we get done really looking at what the minimal capability of landing on land and having the crew walk away, we’ll see what the design looks like, and if the design is robust enough we could return to having nominal land landings.”

One challenge for the Constellation program has been getting the CEV light enough for the Ares rockets to be able to launch it, and therefore eliminating the 1500 lb airbags for landing has its appeal.

“The predominant design philosophy for Orion and Ares 1 has been that we are designing for lunar missions,” continued Hanley. “We will service the International Space Station within that set of capabilities. From that perspective, designing a lot of mass into the spacecraft just to enable land landings has not traded out to be an effective use of our performance. That’s the major consideration in play. Right behind that are life cycle costs.”

Making the decision of land vs. water is the goal for 2008 for the Constellation program. “We’ve studied and have cost estimates for water landings against the infrastructure costs of having multiple landing sites on land and they are comparable,” said Hanley. Right now, NASA is looking at a single target landing zone off the coast of California with one or two recovery vessels.

But they are keeping their options open for a land landing. “If the Orion team is able to come in at the preliminary design review later this next year with a concept for be able to land on land that is fairly robust but not cost a lot of mass to have to hurl to the moon and back, then it becomes an operational decision,” said Hanley.

There has been much debate about what type of landing would be best. “There’s been a lot of assumptions made that landing on land is going to be better, but there are lot of people in the technical community that do not buy into that,” said Hanley. “There’s been a lot of debate surrounding whether or not land landing truly is better from a life cycle cost perspective and there isn’t a lot of quantitative data to really pull from.”

Hanley feels there are assumptions being made but not a lot of substantive date to clarify what the right answer is. So the next steps are to get the spacecraft to a detailed preliminary design and really interrogate the water vs. land issue. That includes further developing the operational concepts , such as how long does the capsule stay in the water, and what loads does the spacecraft see from landing on water and land. Those are all questions that need to be answered in order to make a final decision on the type of landing that will be used.

Stay tuned, as 2008 should be a year of decision for many details about Constellation and the CEV.

Original News Source: NASA News Audio

Posted on by Nancy Atkinson

Shuttle Launch Delayed Until January 2

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Space shuttle Atlantis’ STS-122 mission to the International Space Station has been further delayed and now is targeted to launch no earlier than Jan. 2. The liftoff date hinges on the resolution of a repeat failure of the shuttle’s fuel sensor system. NASA has not yet made a final decision if repairs to the system will be done on the launch pad or if Atlantis will need to be rolled back to the Vehicle Assembly Building where the external tank can be removed.

“It would depend on what we find…but we have a lot of options in front of us,� said NASA’s Mission Management Team chairman LeRoy Cain at Sunday morning press briefing. Cain added that if they do decide to roll back, that probably would not support a January 2 launch. However, STS-122 Launch Director Doug Lyons said he couldn’t envision a scenario that would necessitate a rollback. “We have almost limitless access (to the tank) and there are not many things we can’t do on the launch pad that we could do at the VAB.�

Early Sunday, one of the four engine cutoff (ECO) sensors inside the liquid hydrogen section of Atlantis’ external fuel tank gave a false reading while the tank was being filled. NASA’s new and updated Launch Commit Criteria require that all four sensors function properly. Following Friday’s launch scrub, the MMT decided to shorten the launch window to one minute in an effort to work around the sensor problem. Upon launch, this would send the shuttle on a direct trajectory to the space station, and would save fuel. Fuel depletion is what drives the need for the ECO sensors which protect the shuttle’s main engines by triggering engine shut down if fuel runs unexpectedly low. But the MMT also added the criteria that a failure of any of the four sensors would prompt a launch scrub.

Previously, the criteria required that three of the four sensors had to function properly. Atlantis’ scheduled launch on Thursday, Dec. 6, was delayed after two liquid hydrogen ECO sensors gave false readings. A third sensor gave a false reading while the tank was being emptied.

Meanwhile, ISS flight controllers informed space station commander Peggy Whitson that she and crewmate Dan Tani likely will be asked to carry out a spacewalk later this month to inspect a problematic solar array rotary joint on the right side of the lab’s main power truss. If the launch of STS-122 had gone as planned, a team of shuttle astronauts would have conducted the inspection.
The crew of STS-122 will come out of quarantine and return to Houston.

The main objective of Atlantis’ mission is to deliver, install and activate the European Space Agency’s Columbus laboratory, which will provide scientists around the world the ability to conduct a variety of life, physical and materials science experiments.

Following STS-122, the next two flights on the shuttle manifest for space station construction are scheduled for launch in mid February and late April. The next flight after that is an August mission to service the Hubble Space Telescope. Bill Gerstenmaier, Associate Administrator of spaceflight operations at NASA said that this delay shouldn’t affect NASA’s ability to complete station construction before the shuttle is scheduled to be retired in 2010. “This doesn’t impact the overall manifest. With the remaining time we can accomplish all the flights,� Gerstenmaier said.

Original News Source: NASA TV

Posted on by Nancy Atkinson

Shuttle Launch No Earlier Than Saturday

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The crew of STS-122 and the Columbus science module will have to wait a little longer for their ride to space. The launch of space shuttle Atlantis has been pushed back to no earlier than Saturday, December 8. After assessing the problem with the engine cutoff sensors that scrubbed Thursday’s scheduled liftoff, NASA’s Mission Management Team decided they needed more time to look at the problem. But even a Saturday launch is a best-case scenario, and further delays loom as a possibility.

Engineers continue to examine the circuitry and NASA will hold a briefing at 5 pm EST today to announce when another launch will be attempted. A Saturday launch would be at 3:43 pm and Sunday at 3:20 pm EST. The forecast for Saturday calls for a 60 percent chance of good weather, improving to 70 percent on Sunday.

Based on data received during fueling on Thursday, engineers believe the problem may involve an open circuit between the sensors in the hydrogen portion of the external fuel tank and an electronic box in the shuttle main engine compartment. Two of four sensors failed in a test that is routinely done during tanking. The fuel cutoff sensor system is one of several that protect the shuttle’s main engines by triggering their shut down if fuel runs unexpectedly low. Launch Commit Criteria require that three of the four sensor systems function properly before liftoff. The sensors also gave another false reading while the tank was being emptied, but are now currently indicating correctly the tank is dry.

The current launch window closes on December 13. If the shuttle can’t launch before then, the next earliest launch date wouldn’t be until January 2. While NASA officials initially said they would try to launch today, after a five hour meeting the Mission Management Team decided to hold off for another day. “We need more time,â€? said LeRoy Cain, Chairman of the MMT. “This (problem) is a little bit new, so we want to sleep on it. I can almost guarantee you we will have some new thinking after we let this team go home and rest.”

Since engineers think the problem lies in an open circuit, currently, NASA doesn’t believe any major repairs in hardware will need to be done, which would cause a longer delay for the launch.

“We’re still hoping, and have reason to believe, that we’re going to get off in December,” said Doug Lyons, NASA’s shuttle launch director, “and that’s what we’re shooting for.”

Atlantis will carry the crew of STS-122 to the International Space Station to deliver the Columbus Science Module. Columbus is the European Space Agency’s major contribution the ISS.

Officials from the ESA were disappointed in the delays, but said that safety is most important. “This is perfectly normal,” said Alan Thirkettle, the ESA’s space station program manager, of the launch delay. “We want to launch on time, but we want to launch right.”

Original News Source: NASA TV

Posted on by Nancy Atkinson

Shuttle Launch Postponed

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A problem with space shuttle Atlantis’ fuel sensors has prompted a scrub of today’s scheduled launch of the STS-122 mission to the International Space Station. During fueling of the shuttle’s external tank, two of four engine cutoff sensors failed. Engineers are working on fixing the problem and NASA will try to launch again tomorrow, Friday, December 7 at 4:09 pm EST.

Sensors located in the hydrogen portion of the tank “failed wet” during fuel loading this morning. That means the sensors could falsely indicate the tank still contains hydrogen in the last stages of the shuttle’s climb to space when it actually is empty. The engines would continue to run, and without fuel, the engines could ignite and explode.

Problems with the engine cutoff sensors have occurred before during tanking, including the first shuttle mission after the Columbia accident, STS-114 with space shuttle Discovery. The failed sensors caused a one-day delay in the launch and after the flight the problem was traced to a faulty connection in electrical cables. NASA hopes that in emptying the tank and then refueling tomorrow the sensors will reset correctly, as was the case with the STS-114 launch.

This shuttle mission, STS-122, will bring the Columbus science module to the ISS. Columbus is the European Space Agency’s cornerstone contribution to the space station. Two ESA astronauts, Hans Schlegel from Germany, and Leopold Eyharts from France, are part of the shuttle crew, and Eyharts will remain on board the station to lead the activation of the new lab. The other astronauts for the mission are Commander Stephen Frick, pilot Alan Poindexter and mission specialists Rex Walheim, Stanley Love, and Leland Melvin.

STS-122 is expected to be an 11 day mission. It is the 121st shuttle flight and the 24th mission to the ISS.

Original News Source: NASA TV