The 30-foot-long, robotic, X-37B military ship — which has gained fame both for its secret missions as well as its ability to stay in orbit for so long — ended its most recent trip at NASA’s Kennedy Space Center in Florida on Saturday, according to Space Force and USA Today. //

The unmanned little spacecraft, which looks like a mini-shuttle, spent a record-breaking 908 days in orbit, or 118 days more than its previous record, USA Today said.

The reusable Boeing vehicle, now done with its sixth mission, has traveled 1.3 billion miles over the course of 3,774 days in space. It has been whizzing around Earth on various trips since 2010.

While X-37B’s primary missions are mainly secretive, it does perform secondary tasks that are publicized, the outlet said.

Several NASA experiments were completed during the record-breaking mission, the military Space Force said in a statement.

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What they uncover off the coast of Florida, outside of the Triangle, marks the first discovery of wreckage from the 1986 Space Shuttle Challenger in more than 25 years.

"Every time we saw a leak, it pretty quickly exceeded our flammability limits." //

So why does NASA use liquid hydrogen as a fuel for its rockets if it is so difficult to work with and there are easier-to-handle alternatives such as methane or kerosene? One reason is that hydrogen is a very efficient fuel, meaning that it provides better "gas mileage" when used in rocket engines. However, the real answer is that Congress mandated that NASA continue to use space shuttle main engines as part of the SLS rocket program. //

Among the idea's opponents was Lori Garver, who served as NASA's deputy administrator at the time. She said the decision to use space shuttle components for the agency's next-generation rocket seemed like a terrible idea, given the challenges of working with hydrogen demonstrated over the previous three decades.

"They took finicky, expensive programs that couldn't fly very often, stacked them together differently, and said now, all of a sudden, it's going to be cheap and easy," she told Ars in August. "Yeah, we've flown them before, but they've proven to be problematic and challenging. This is one of the things that boggled my mind. What about it was going to change? I attribute it to this sort of group think, the contractors and the self-licking ice cream cone." //

niwaxArs Tribunus Militumet Subscriptorreply3 days agoReader Favreportignore user
Update: At current funding levels, the delay to mid-october costs $495 million, or the total development cost of Falcon Heavy, or the total development cost of Falcon 9 plus four flights.

The Mars Oxygen In-Situ Resource Utilization Experiment can make oxygen at anytime during the Martian day or year.

NASA confirmed Wednesday that it has awarded five additional crew transportation missions to SpaceX, and its Crew Dragon vehicle, to ferry astronauts to the International Space Station. This brings to 14 the total number of crewed missions that SpaceX is contracted to fly for NASA through 2030.

As previously reported by Ars, these are likely the final flights NASA needs to keep the space station fully occupied into the year 2030. While there are no international agreements yet signed, NASA has signaled that it would like to continue flying the orbiting laboratory until 2030, by which time one or more US commercial space stations should be operational in low Earth orbit.

Under the new agreement, SpaceX would fly 14 crewed missions to the station on Crew Dragon, and Boeing would fly six during the lifetime of the station. That would be enough to fill all of NASA's needs, which include two launches a year, carrying four astronauts each. But NASA has an option to buy more seats from either provider. //

SpaceX started flying operational missions to the space station in 2020, with the Crew-1 mission. Although Boeing's Starliner has a crewed test flight early next year, likely in February, its first operational mission will not come before the second half of 2023.

Additionally, there is some question about the availability of rockets for Starliner. Boeing has purchased enough Atlas V rockets from United Launch Alliance for six operational Starliner missions, but after that the Atlas V will be retired. During a news conference last week, Boeing's program manager for commercial crew, Mark Nappi, said the company is looking at "different options" for Starliner launch vehicles. These options include buying a Falcon 9 from a competitor, SpaceX, paying United Launch Alliance to human-rate its new Vulcan rocket, or paying Blue Origin for its forthcoming New Glenn booster. //

Since we now know how many flights each company will be providing NASA through the lifetime of the International Space Station, and the full cost of those contracts, we can break down the price NASA is paying each company per seat by amortizing the development costs.

Boeing, in flying 24 astronauts, has a per-seat price of $183 million. SpaceX, in flying 56 astronauts during the same time frame, has a seat price of $88 million. Thus, NASA is paying Boeing 2.1 times the price per seat that it is paying SpaceX, inclusive of development costs incurred by NASA. //

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ColdWetDog wrote:
Interesting that the $90 million lasts charged by Roscosmos isn't too far off the SpaceX cost.

The Russians were seen to be price gouging - and in a way that's true, the Soyuz development costs have been paid back years ago - but it wasn't too outrageous of a price in retrospect.

Of course, giving the money to SpaceX has many other advantages.

It's not a good comparison regarding Roscosmos seat price because the SpaceX "seat price" actually includes the complete capacity of the Dragon and it's trunk for cargo up mass and down mass.

ISS High Definition Live Streaming Video of the Earth (HDEV)

Currently, live video of Earth is streaming from an external HD camera mounted on the ISS. The camera is looking toward Earth with an occasional solar panel passing through the view.

In addition to flying, landing, and returning from the moon in 1969 — NASA's Apollo 11 crew helped with a series of scientific experiments. One of them was to leave a special instrument with lots of little reflectors on the surface of the moon. The goal of that experiment was to beam a laser at the moon. Today on the show, Scientist-In-Residence Regina G. Barber talks to host Aaron Scott about the lunar laser ranging experiment — and how shooting that laser helped us better understand one of Einstein's theories.

Under the current limits, set by NASA in 1989, the effective dose limit for an astronaut's career is based on a maximum 3% lifetime excess risk of cancer mortality. That risk is evaluated with a sliding scale based on age and sex, ranging from a lower career limit of 180 millisieverts (mSv) of radiation for a 30-year-old woman to an upper career limit of 700 mSv for a 60-year-old man.

So why is there a lower career limit for radiation exposure for female astronauts than for male astronauts?

According to R. Julian Preston, a special government employee with the U.S. Environmental Protection Agency's Radiation Protection division, NASA's lower radiation threshold for female astronauts was based on the following finding: When women and men were exposed to high levels of radiation for similar periods of time, women had more than twice the risk that men did of developing lung cancer. //

"It has been generally considered — based largely on the survivors from the atomic bombs in Japan — that, particularly for lung cancer, that women were more sensitive" to ionizing radiation than men were, Preston, who serves on committees for the National Council on Radiological Protection and Measurements, told Live Science. //

However, NASA's radiation thresholds are expected to change in the near future. In 2021, NASA asked a panel of experts convened by the National Academies of Sciences, Engineering and Medicine to assess the space agency's plan to change its career radiation limit to 600 mSv for all astronauts of all ages. NASA determined that limit by applying the agency's cancer risk model to the most susceptible individuals: early-career women. NASA calculated the average risk of exposure-induced death for this group and converted that risk, which allows for a much larger margin of error than previously, to a dose. That 600-mSv dose translates to the exposure an astronaut would receive during four six-month expeditions on the ISS. For comparison, the average annual dose of radiation received by a person on Earth is about 3.6 mSv, according to NASA, versus 300 mSv per year on the ISS.

Appearing before a House Science Committee hearing on NASA's Artemis program, Martin revealed the operational costs of the big rocket and spacecraft for the first time. Moreover, he took aim at NASA and particularly its large aerospace contractors for their "very poor" performance in developing these vehicles.

Martin said that the operational costs alone for a single Artemis launch—for just the rocket, Orion spacecraft, and ground systems—will total $4.1 billion. This is, he said, "a price tag that strikes us as unsustainable." With this comment, Martin essentially threw down his gauntlet and said NASA cannot have a meaningful exploration program based around SLS and Orion at this cost.

Later in the hearing, Martin broke down the costs per flight, which will apply to at least the first four launches of the Artemis program: $2.2 billion to build a single SLS rocket, $568 million for ground systems, $1 billion for an Orion spacecraft, and $300 million to the European Space Agency for Orion's Service Module. NASA, Martin said, had checked and confirmed these figures.

What is striking about these costs is that they do not include the tens of billions of dollars that NASA has already spent developing the Orion spacecraft since 2005 and the Space Launch System rocket since 2011. If one were to amortize development costs over 10 flights of the SLS rocket and Orion spacecraft, the $4.1 billion figure cited by Martin would easily double. //

Later during the hearing, US Rep. Brian Babin (R-Texas), asked whether the incremental costs of flying more than one Artemis mission a year would bring the cost down. Martin said he did not know for sure. Moreover, NASA is not planning to fly more than one Artemis mission a year, so the question is somewhat moot.

Martin, however, appeared to doubt that there would be significant cost savings due to the inefficiency of the program and its large aerospace contractors.

"Part of it goes to the efficiencies of the underlying contractors, like Boeing," Martin said. "One of the problems we saw in development of the SLS and Orion—it's a challenging development of course—but we did notice very poor contractor performance on Boeing's part, poor planning, and poor execution."

Then, unprompted, Martin continued to criticize the programs set up by Congress to fund the rocket and spacecraft. House and Senate members told NASA to use "cost-plus" contracts, which ensure that companies involved in the development and operation of these systems receive all of their costs, plus a fee. This tends to disincentivize timely work completed within a set budget. (Remarkably, NASA was told to continue using cost-plus contracts even after the development program.)

"We saw that the cost-plus contracts that NASA had been using to develop that combined SLS-Orion system worked to the contractors' rather than NASA's advantage," Martin said. //

In reality, no one should expect Congress to care about the high cost of the SLS and Orion program. The legislature created the programs this way. //

In fact, key members of Congress have been critical of NASA every time the agency has tried to break free of cost-plus contracting and use a more commercial approach through fixed-price contracts. That congressional skepticism has persisted even as the commercial approach has borne fruit. As tensions with Russia rise, for instance, NASA only has independent access to space because of the Crew Dragon spacecraft.

Lest anyone doubt this, House Science Committee Chair Eddie Bernice Johnson (D-Texas) took aim at NASA's commercial space efforts in her opening statement at the hearing. The context of her statement concerns NASA's desire to purchase commercial services for spaceflight in the future rather than oversee their development in-house like it did with SLS and Orion.

"I find the sum of these actions to be very troubling," Johnson said. "And it raises the question of whether NASA will even retain the capabilities and workforce within the agency that will be needed to get US astronauts to Mars if all of these privatization plans are realized."

At least it answers the question of where congressional priorities lie.

Russia's unprovoked invasion of Ukraine this week will have devastating consequences for the people on the ground. Although the terrestrial implications of this war are far greater than those for spaceflight, there will nonetheless be ripple effects felt by space programs around the world. //

The most prominent space issue concerns the fate of the International Space Station, which is operated by 15 nations but led by the United States and Russia. The countries rely on one another: Russia provides fuel and thruster capability to periodically re-boost the space station to a higher altitude, and NASA gyroscopes provide stability, and its solar panels generate the vast majority of electricity. At present, the station cannot operate without the consent of both partners.

After Biden's comments on Thursday, the head of Russia's main space corporation, Dmitry Rogozin, lashed out in a series of tweets in which he characterized Biden's actions as "Alzheimer's Sanctions." //

All of this translates into fewer resources pouring into the Russian space program and a further diminution of its activities. Without investment, the country is unlikely to be able to afford any semblance of deep-space activities or the creation of its own space station as a follow-on to the International Space Station.

This very likely will push Russia to cooperate further with China, where it has already initiated discussions about joining the Chinese lunar exploration program. But this Chinese lifeline will almost certainly come with costs. China will be interested in partnering with Russia to promote the idea that it is leading an international exploration program—but Russia should have no illusions about who will be driving the bus and who will be along for the ride.

Fifty years ago Friday, on Dec. 21, 1968, Apollo 8 lifted off, marking the first time humans left low Earth orbit and flew to the moon.

This was the second manned spaceflight of the Apollo program, and it was a nerve-wracking and remarkable flight that captured the world's attention. The mission capped a difficult and conflict-filled year in the U.S., offering a rare moment when people could feel good about their planet.

Any trip to space is risky. But a mission to the moon, nearly a quarter-million miles from Earth, was something else. There were many things that could go wrong and many unknowns about this first trip. But on Christmas Eve 1968, the capsule made it to lunar orbit. //

There was also an unexpected moment during the 20 hours they circled the moon. As they focused on the lunar surface below, something else caught the crew's attention.

"Oh my God, look at that picture over there! It's the Earth coming up. Wow, is that pretty!" exclaimed Anders.

Anders rushed to snap a picture of the Earth, rising above the barren lunar landscape. The "Earthrise" image remains one of the most famous ever taken in space, and Anders says it forever changed the way people think about where we live.

"The only color that we could see and contrasted by this really unfriendly, stark lunar horizon, made me think, 'You know, we really live on a beautiful little planet,' " he says. //

In an interview with NPR earlier this year, Borman, the mission commander, noticed the same thing. "The only telegram I remember out of all the thousands we got after Apollo 8 said, 'Thank you Apollo 8 you saved 1968,' " he said.

Aug 5, 2015

From a Million Miles Away, NASA Camera Shows Moon Crossing Face of Earth
A NASA camera aboard the Deep Space Climate Observatory (DSCOVR) satellite captured a unique view of the moon as it moved in front of the sunlit side of Earth last month. The series of test images shows the fully illuminated “dark side” of the moon that is never visible from Earth.

The images were captured by NASA’s Earth Polychromatic Imaging Camera (EPIC), a four megapixel CCD camera and telescope on the DSCOVR satellite orbiting 1 million miles from Earth. From its position between the sun and Earth, DSCOVR conducts its primary mission of real-time solar wind monitoring for the National Oceanic and Atmospheric Administration (NOAA).

When I was last down at Edwards AFB, I also spent some time at what is now known as Armstrong Flight Research Center. Before the name change in 2014, it had been famously titled the Dryden Flight Research Center. During my time with the awesome public affairs team there, a photo on the wall grabbed my attention. It was an incredible image of one of NASA's two Shuttle Carrier Aircraft (SCA) with the Orbiter Endeavor mated to its back as it flew over a gorgeous desert landscape. But what made the shot so amazing was how the perspective was from directly above, looking down.

I was told that the photo, taken in December of 2008 as Endeavor made its voyage back to Kennedy Space Center in Florida, was one of the most beloved in at the installation and that it was shot by one of NASA's most acclaimed photographers, Carla Thomas. If I remember correctly, the photo was planned ahead of time and executed perfectly from the back seat of Armstrong's F/A-18B. The aircraft had rolled inverted—or near inverted—to capture the unique angle of the loaded-up SCA.

The use of an IRCM system to protect NASA's prized shuttle-carrying 747s during its 1983 visit to the Paris Air Show and other stops along the way is certainly intriguing. What started out as a technical interest for us turned into something of a Cold War mystery. The big question remains: what intelligence led to such a drastic measure being taken and who supplied that intelligence to NASA?

On Christmas morning of 2021, the James Webb Space Telescope successfully launched from Earth. Thomas Zurbuchen, now NASA's associate administrator for science, had made the call. If Webb was going to fail, he would take the blame.

Not only did Webb launch, but its Ariane 5 rocket performed the flight with such precision that the spacecraft was able to save precious fuel for maneuvering, thereby extending its lifetime. Over the next two weeks, engineers and scientists executed hundreds of steps to unfold and fully extend the telescope and its massive sunshield. And then, finally, on Monday, the spacecraft performed one final major burn of its thrusters, falling into a halo orbit around the L2 point.

This means that the Webb space telescope has reached its final destination, a 180-day orbit around this L2 point, which keeps the telescope in line with the Earth as both the instrument and planet orbit around the Sun. Here, while using a minimum amount of fuel to hold its position, Webb can use its sunshield to keep the infrared telescope and its instruments cold.

The work is not done. The telescope has 18 primary mirror segments, which are moved by 132 actuators. These actuators have already been tested and shown to work. Now, over the next three months, telescope operators will fine-tune the alignment of these mirrors. During this process, scientists will use a Sun-like star named HD84406 to focus the mirrors. This star is located about 240 light years from Earth and can be found in Ursa Major near the bowl of the Big Dipper.

At the same time, in the wake of the sunshield, these mirrors and their scientific instruments will continue to cool in order to be able to detect the weak, ultra-distant signals of heat from the Universe's oldest galaxies. //

What is it about HD84406 that makes it the one to use for focusing the mirrors?

There are probably lots of criteria, but I only know two of them:

1. It's in the same 1/3 of space that JWST can see (i.e. the telescope doesn't have to look towards the Sun to see it)
2. It has to be relatively bright (HD84406 is not visible to the naked eye but can be seen with binoculars).

I can't find a reference now, but IIRC it was also selected because it's isolated with nothing behind it that's close (in interstellar terms), so it's easier to determine if the focus is good because there's less background light.

How on Earth do you patch the software on a computer orbiting the Moon? Very carefully.

FRANK O’BRIEN - 1/30/2020, 12:30 PM

In the afternoon of January 31, 1971, the flight thundered away from the Kennedy Space Center on its Saturn V launch vehicle after only a brief 40 minute hold for weather. After restarting the S-IVB third stage for trans-lunar injection (TLI), the command module Kitty Hawk and her crew were on their way to the Moon. //

However, less than four hours before the scheduled landing, controllers noticed that according to the indications on their consoles in Mission Control, the LM's Abort pushbutton appeared to have been pressed. When asked via radio, Shepard confirmed that no one on board Antares had pressed the Abort button—which meant there was a short-circuit or other electrical issue somewhere inside the LM's complicated guts.

This was potentially a mission-ending problem: if the button was pressed and the engine was firing, the LM would immediately begin its abort procedure as soon as the lunar descent started, making a landing impossible.

Under hard time pressure, the ground had to quickly figure out what was wrong and devise a workaround. What they came up with was the most brilliant computer hack of the entire Apollo program, and possibly in the entire history of electronic computing.

To explain exactly what the hack was, how it functioned, and the issues facing the developers during its creation, we need to dig deep into how the Apollo Guidance Computer worked. Hold onto your hats, Ars readers—we're going in. //

Once again the LM’s orbit carried it behind the Moon and out of communications, leaving the crew with just a smattering of procedures and few options. The normal work of finishing the system configurations continued, and the crew maneuvered to the descent attitude, tidied up the cabin, and put on their helmets and gloves. In the meantime, Don Eyles’ team was feverishly working to find a better solution to the Abort bit issue.

Working the problem involved unraveling a complex, daisy-chained series of events. The main landing program, P63, does not perform all of the landing computations itself. Rather, it orchestrates a large number of Jobs and Waitlist Tasks, each performing a necessary part of the effort. Another Job running concurrently was the SERVICER, which sampled attitudes and accelerations that fed into the guidance equations. SERVICER, in turn, scheduled Routine R11 as a Waitlist Task, running every 0.25 seconds. R11 first checked whether aborts are enabled (via the LETABBIT flag), and if so, it then checked the status of the Abort bit. With aborts allowed, and the abort signal set (presumably because the crew pressed the Abort pushbutton), P63 is terminated, the AGC's Major Mode switches to P70, and the abort process begins. //

This was the breakthrough. If R11 could be spoofed into believing that an abort was already in progress, then it didn’t matter if the Abort button was pressed or not—the button's state would be ignored.

But how did R11 actually inform itself about whether or not an abort was executing? The answer was in plain sight on the DSKY: The Major Mode display, under the label “PROG”. //

In less than two minutes after the descent to the Moon had started, the Abort pushbutton had been successfully disabled and the computer was happily managing the descent. All indications were that the next lunar landing would be successfully accomplished in eight more minutes. //

As Antares passed through 32,000 feet (about 9,700 meters), Mitchell became concerned and informed controllers that the radar hadn’t locked on. Houston replied with a suggestion to pull the circuit breaker for the radar, and then power the system back on, which did the trick. Solid radar data began flowing into the computer, and the crew quickly agreed to accept it. Just a few minutes later, Shepard made a smooth and on-target touchdown at the Fra Mauro highlands.

After the mission, when asked if he would have attempted to land without the radar, the notoriously hard-charging Shepard reportedly replied, “You’ll never know.” In Gene Kranz’s Failure is Not an Option autobio, Kranz recounts that Flight Director Jerry Griffin was convinced that Shepard would indeed make an attempt to land without radar, and would just as certainly have had to abort when fuel ran out. //

The idea that a single errant switch could derail a lunar landing attempt was unacceptable. After the mission, a new variable in the AGC code was introduced that allowed the crew to "mask out" (that is, to ignore) the Abort and Abort Stage pushbuttons. The scenario assumed that a failing switch would be recognized well before the descent began, and commands could be entered in time to prevent an inadvertent abort. Like the fix used for Apollo 14, this would make initiating an abort through a pushbutton impossible, and any urgent situation would have to be performed on the Abort Guidance System. //

The recovery from Apollo 14’s Abort switch failure can only be described as brilliant and heroic. But the most important enabler of this effort was that the software, while fiendishly complex, could be understood by a small team of developers. Modern hardware and software, with its extensive protection schemes, virtualization and dynamic program management simply would make such a simple hack impossible. Faced with a comparable problem today, even if the fix were trivial, the solution likely would require large amounts of code to be recompiled, tested and uploaded to the spacecraft. This may not be possible given the short timeframe necessary to save the mission.

In the end, Apollo 14’s fix truly represented the “Spirit of Apollo," where talented teams made the impossible happen.

The other piece of news, less well-covered but still important, emerged during a news conference on Saturday. NASA's Mission Systems Engineer for the Webb telescope, Mike Menzel, said the agency had completed its analysis of how much "extra" fuel remained on board the telescope. Roughly speaking, Menzel said, Webb has enough propellant on board for 20 years of life.

This is twice the conservative pre-launch estimate for Webb's lifetime of a decade, and it largely comes down to the performance of the European Ariane 5 rocket that launched Webb on a precise trajectory on Christmas Day.

Prior to launch, the telescope was fueled with 240 liters of hydrazine fuel and dinitrogen tetroxide oxidizer. Some of this fuel was needed for course adjustments along the journey to the point in space, about 1.5 million km from Earth, where Webb will conduct science observations. The remainder will be used at Webb's final orbit around the L2 Lagrange point for station-keeping and to maintain its orbit.

So every kilogram of fuel saved on Webb's journey to the Lagrange point could be used to extend its life there. Because ten years seemed like a fairly short operational period for such an expensive and capable space telescope, NASA had already been contemplating a costly and risky robotic refueling mission. But now that should not be necessary, as Webb has at least two decades of life.

A lot of this comes down to the performance of the venerable Ariane 5 rocket. NASA and the European Space Agency reached an agreement more than a decade ago by which Europe would use its reliable Ariane 5 rocket to lift the telescope into space, and in exchange, European scientists would get time to use the telescope. //

The Ariane 5 program also selected the best components for Webb based upon pre-flight testing. For example, for the Webb-designated rocket, the program used a main engine that had been especially precise during testing. "It was one of the best Vulcain engines that we've ever built," Albat said. "It has very precise performance. It would have been criminal not to do it." //

Albat admitted that the days prior to launch were exhausting and nerve-wracking. But soon after the launch, Albat said he and the entire European space community could take pride as Webb took flight and began to unfurl its wings. Now, he said, "I feel totally relaxed." The same can be said for a lot of scientists who have been watching Webb's development for two decades.

The temperatures measured where the oxidizer enters the vehicle at an umbilical connection were about four degrees Rankine or Fahrenheit too high. “The requirement is about 169.1 Rankine, that’s -290.57 degrees Fahrenheit, so we didn’t quite get there on Monday,” Bassler explained. “What we saw at the temperature for the interface to the Core Stage was 173 Rankine, which is -286.67 degrees Fahrenheit.”

A slow flow rate of propellant chills down the facility and vehicle lines to start the loading process, so they aren’t shocked by the sharp, several-hundred degree drop in their temperature. Normally after the chilldown phase, the loading transitions to a slow fill phase, which is at a higher flow rate, and then a fast fill phase to load the propellant tank to the top.

The concern with the warmer propellant in the early phases of loading is geysering. “The thing that the team is trying to protect in the [temperature] limits that got tripped are relative to the concern of developing a gas bubble in [a] feedline,” SLS Program Manager John Honeycutt said. “[A bubble] could end up collapsing and then you could have quite a bit of energy released when the liquid oxygen above that bubble could release and fall back down the feedline.”

The five layers of the sunshield are incredibly delicate. Each plastic-like sheet has the same thickness as a human hair and had to be stretched across a tennis-court-sized area. All of this had to be done in microgravity, an environment that could not be simulated in ground tests.

"It was the first time we deployed this system in zero-g, and we nailed it," said Alphonso Stewart, Webb deployment systems lead. "It's a really good testament to the work done by the teams."

So much could have gone wrong. During tests as recently as 2018, the sunshield layers were snagging during ground-based tests. It's not difficult to understand why. According to NASA, the unfolding and tensioning of the sunshield involved 139 of the telescope's 178 release mechanisms, 70 hinge assemblies, eight deployment motors, some 400 pulleys, and 90 individual cables totaling more than 400 meters in length.

By getting through the sunshield deployment process, therefore, NASA has surmounted the most complex aspect of unpacking the telescope in space and setting it up for operations.

"The sunshield deployment certainly was the most complex in terms of moving parts having to all work in harmony, and systems that were interrelated with one another," said James Cooper, the Webb telescope's sunshield manager. "The stuff that’s left from a deployment point of view is more conventional, such as hinges and motors."

The American astronauts calculated critical course-correction maneuvers on their HP-65 programmable hand-held during the rendezvous of the U.S. and Russian spacecraft.