Tag Archives: spaceflight

Europe’s Galileo GPS-type constellation back up and running

Europe’s Galileo GPS-type constellation was back up and running on July 18, though it remains unclear exactly what caused the failure in both of its ground facilities.

Officials have only provided this tantalizing hint:

“The technical incident originated by an equipment malfunction in the Galileo control centers that calculate time and orbit predictions, and which are used to compute the navigation message,” the GSA wrote on Thursday in its most specific statement yet. “The malfunction affected different elements on both centers.”

That generally confirms what researchers who use the Galileo system had noticed independently. Satellites transmit packages of data to Earth that convey a set of astronomical positioning and timing data, used to compute satellite orbits and positions. But some combination of errors in the Galileo processing system led it to base these calculations on the wrong date, for example, using July 11 time stamps—the day the outage began—throughout the week. Eventually, the system even interpreted this data as referring to July 18, instead of the previous Thursday. The frozen time stamp seemed to be a symptom of problems with the ground-based processing system, rather than the satellites themselves.

This sure sounds like a computer hack that took down the systems at both facilities, suggesting that the security of Europe’s Galileo system has some very big holes.

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China deorbits Tiangong-2

China yesterday successfully deorbited its second space station test module, Tiangong-2, landing it harmlessly over the south Pacific.

Meanwhile the date of next launch of Launch March 5, the rocket that China must have operational in order to launch its full space station, remains unknown. It had been expected in July, but it appears this will not happen, and there is no indication when it will fly.

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Soyuz launches new crew to ISS

The Russians today launched and docked a new crew to ISS using their Soyuz rocket and capsule.

This launch puts Russia ahead of SpaceX in the 2019 launch race, the first time Russia has been ahead of SpaceX in almost two years. It also puts Russia in a tie with China for the lead, also something that has not been the case in two years. The leaders:

9 China
9 Russia
8 SpaceX
5 Europe (Arianespace)

The U.S. still leads 14-9 over China and Russia in the national rankings.

Posted from the south rim of the Grand Canyon after our hike out today.

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The Untouched Moon

Montes Carpatus
Click for full image.

In celebration of Apollo 11: Continuing the theme of yesterday’s cool image, where I noted how little of the Moon we have really seen, today’s cool image gives us a breath-taking glimpse of one such untouched region, the Montes Carpatus region.

The photograph to the right, reduced to post here, was released by the Lunar Reconnaissance Orbiter (LRO) science team in March 2018. From the release:

Volcanic rocks are our best window to the deep interior of the Moon, and the Montes Carpatus has no shortage of volcanic landforms: lava flows, pyroclatic deposits, rilles, and more! Lavas are formed as the mantle begins to melt, so by sampling volcanic rocks of various ages from regions across the Moon scientists can reconstruct the range of compositions and processes over time. The Montes Carpatus formed as a result of the giant impact that formed the mighty Imbrium basin, the mountains are actually the raised rim of the basin.

Today is the 50th anniversary of the Apollo 11 landing. If you had told anyone involved in that mission that fifty years later no significant further manned exploration of the Moon had yet occurred, they would have scoffed.

It is a terrible condemnation of my generation, the generation that followed Apollo 11, that we did nothing grand like this. I challenge the generations today to reach higher, and do better.

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July 20, 1969: “One small step…”

An evening pause: In honor of the fiftieth anniversary.

Neil Armstrong takes the first steps on the Moon. Note his focus is almost entirely on describing what he sees and experiences. He is doing this for two reasons, first to provide knowledge of the Moon to the world, and second to provide engineers as much information as possible for future missions.

This focus explains why the first thing he does is to get a contingency rock sample, just in case they need to leave the Moon quickly.

Note also that when Buzz Aldrin joins Armstrong on the surface, he is as professional and calm, proving that the way he has been portrayed by some recent movies as as undisciplined jerk is simply a slander. He would not have been picked for this mission if he really behaved that way.

He wanted to be the first, and lobbied to get that chance. After the decision was made he got down to work to make the mission a success.

For a different view of these same events, watch this video.

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July 20, 1969: “The Eagle has landed”

An evening pause: In honor of the fiftieth anniversary.

Note the calm tone in all the voices, even when something is not quite right. To do really great things, one must not let one’s emotions run the show. You need to be cool-headed and focused on the task at at hand. If only today’s adult generation, especially in the world of politics, would do the same.

Just before Armstrong brings Eagle down, you will hear a voice say “60 seconds,” then “30 seconds.” That is mission control telling him how much time they estimate he has before he runs out of fuel.

Below the fold is the same last few minutes of the landing, produced by the Lunar Reconnaissance Orbiter (LRO) science team using its high resolution images to recreate a simulation of what Armstrong saw in his window. Remember, the view in the original 16mm film was out Aldrin’s window.

» Read more

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The Taurus-Littrow valley

Taurus-Littrow Valley
Click for full image.

It might not be Apollo 11, but during this 50th anniversary week of that mission, why not look at where the last Apollo 17 crew landed, in the middle of the Taurus-Littrow valley, as shown on the right in a Lunar Reconnaissance Orbiter (LR) image released by the LRO science team in 2018.

The image illustrates how ambitious NASA had become by this last Apollo mission. The Apollo 11 site was chosen because it was flat with as few risks as possible. By Apollo 17, the Apollo engineers and astronauts were quite willing to drop the LM down into this valley between gigantic mountains. Granted, the valley was more than 400 miles wide, but considering the risks of every Apollo flight, the choice was daring to say the least.

Taurus-Littrow also has a cluster of craters believed to have been formed by material flung out from the formation of 86-kilometer-wide Tycho crater about 100 million years ago. Tycho is 2250 kilometers from Taurus-Littrow, but the impact that formed it was violent enough that it cast material far across the Moon.

Nor is this location the most spectacular on the Moon. In fact, considering that all the manned and unmanned missions in total have probably covered less ground than a New York cab driver does in a single day, we have seen almost nothing there.

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ULA delays Delta 4 and Atlas 5 launches for same reason

Because of a concern about the same component used on both its Atlas 5 and Delta 4 rockets, ULA has now delayed the upcoming launches of both rockets.

Concerns over an unspecified part flying on the upper stages of United Launch Alliance’s rockets have delayed the launch of a GPS satellite on a Delta 4 booster from July 25 to no earlier than Aug. 22.

The same issue has also delayed an Atlas 5 launch.

The delays are related to engineers’ concerns over a common component that flies on the upper stages of the Atlas 5 and Delta 4 rockets, a ULA spokesperson said Wednesday.

Both rockets use the same Aeroject Rocketdyne engine in their upper stages, but an official from that companY said that its engine is not the issue. The upper stages also use the same avionics systems.

Posted from the rim of the Grand Canyon.

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Eagle undocks, Apollo 11, July 20, 1969

An evening pause: In honor of the fiftieth anniversary of Apollo 11, today’s evening pause shows the moment when the lunar module Eagle undocked from the command module Columbia. Though this video includes communications with mission control at the start, the actual undocking occurred on the back side of the moon, when the astronauts were out of touch with the Earth.

Near the end of the video, after they have reacquired communications with the ground, you can hear a recitation of a long string of numbers. This is mission control providing the astronauts the numbers that had to be uploaded into their onboard computer so that it could correctly fire the spacecraft engines at the right time and for the right duration.

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A wave on the Moon

A lunar ejector blanket

Continuing this week’s celebration of the 50th anniversary of the Apollo 11 mission means we get to look at another cool image from the Moon. The photograph on the right, reduced to post here, was released by the Lunar Reconnaissance Orbiter (LRO) science team in 2016.

What are we looking at? At first glance it looks like a black & white photograph of The Wave in northern Arizona. What it is instead is the pattern of ejecta laid down across the surrounding terrain immediately after the impact that created relatively fresh Chaplygin Crater. From the website:

The delicate patterns of flow across, over, and down local topography clearly show that ejecta traveled as a ground hugging flow for great distances, rather than simply being tossed out on a ballistic trajectory. Very near the rim lies a dark, lacy, discontinuous crust of now frozen impact melt. Clearly this dark material is on top of the bright material so it was the very last material ejected from the crater.

Below the fold is a wider shot of the entire crater and its surrounding terrain, with the rectangle indicating the region covered by the close-up above The dark crust near the rim mentioned in the quote can clearly be seen.
» Read more

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NASA admits that 1st SLS launch likely to be delayed to 2021

In testimony yesterday at a House hearing NASA administrator Jim Bridenstine twice hinted that SLS’s first launch will not occur as scheduled in 2020, but will be delayed until 2021.

Twice during testimony before the US Senate Committee on Commerce, Science, and Transportation, Bridenstine referenced 2021 as the expected launch date for Artemis-1. “I think 2021 is definitely achievable for the Artemis-1 launch vehicle,” Bridenstine said in response to a question from Sen. Roger Wicker, the Mississippi Republican who chairs the committee.

However, Bridenstine said he would not set a new date for the mission yet.

Meanwhile, internal NASA sources say the launch can’t happen earlier than late 2021, and then only if the agency gets a lot more money, over and above the more than $25 billion that Congress has alocated.

Falcon Heavy was developed for $500 million. It took seven years, and is now operational, having flown three times. If the first launch of SLS does not occur until 2021 it will have taken NASA seventeen years to make that flight, for fifty times the money.

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India reschedules Chandrayaan-2 launch

The new colonial movement: India’s space agency ISRO have rescheduled the launch of Chandrayaan-2 lunar orbiter/lander/rover now for July 22, 2019.

The new launch date apparently requires a very short launch window.

July 15 had offered the most comfortable launch window of 10 minutes for the Mission. But Isro has managed to successfully launch several satellites within one-minute windows in the past. However, delaying beyond July 31 could have potentially reduced the Orbiter’s life around the Moon.

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Weird lunar crater

Concentric crater in Apollo Basin on the Moon

In celebration of the 50th anniversary of the Apollo 11 mission, it is time for another cool image from the Moon. The photograph on the right, reduced to post here, was taken by Lunar Reconnaissance Orbiter (LRO) in 2013. It shows a weird crater with concentric features that is found within Apollo Basin, a large 334-mile-wide double-ringed impact feature in the southern hemisphere of the Moon’s far side.

Concentric craters have an inner rim whose formation mechanism is not yet entirely understood, but the concentric mounds may indicate that there is a discontinuity, such as layers with different strengths, in the subsurface excavated by the impact.

Or to put it more bluntly, they really have no idea why this crater ended up looking as it does.

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Starhopper static engine test engulfs vehicle in flames

Capitalism in space: A Starhopper static engine test yesterday testing the newly installed Raptor engine resulted in the vehicle being engulfed in flames.

While the test itself appeared to fire for its full duration, events relating to this test appeared to cause some issues with Hopper, later seen when a secondary fire rose up to engulf the test vehicle. This is understood to have been related to two small fires – one on the vehicle and one on the pad.

A discharge of methane – during the safing of the vehicle, which involved a fire hose being directed at the small fires – ignited and caused a fireball to rise from the aft of the vehicle.

However, the vehicle survived and photos show it is suffering from no obvious damage from external views. This was backed up by a successful detanking and power down overnight.

I have embedded a slow motion video of the test below the fold, with that secondary fire occurring at about 50 seconds in, at about the moment it appears a stream of water hits a smaller fire.

Their plans had been to follow this static test with a 20 meter vertical flight of Starhopper, unattached. When this will occur is now unclear.
» Read more

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Apollo 11 First Stage liftoff

An evening pause: This was originally posted as an evening pause in 2016. I think that today, the fiftieth anniversary of the launch of Apollo 11, it is appropriate to repost it. As I wrote then,

Though the video is more than 8 minutes long, the actual events recorded lasted only about 30 seconds, beginning 5 seconds before T minus 0.

What struck me most as I watched this was the incredible amount of complex engineering that went into every single small detail of the rocket and the launch tower and launchpad. We tend to take for granted the difficulty of rocket engineering. This video will make you appreciate it again.

It is also mesmerizing. A lot happens in a very short period of time.

Tonight’s evening pause begins eight days of pauses dedicated to celebrating, and reliving, the Apollo 11 mission. To the Moon!

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Apollo 11 in real time

Link here. I should have posted this link earlier. As I post this the Saturn 5 has just launched.

Pick your moment. They will be showing the mission in real time over the next week.

Hat tip Steve Golson for prompting me.

Correction: If you go to the link you can either choose to watch from one minute before launch, or click on the “Now” button to see the status at this moment fifty years ago.

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A lunar crater wall two miles high

Giordano Bruno crater

Cool image time! Considering this week is the 50th anniversary of the Apollo 11 lunar landing, it seems appropriate to show some cool images from the Moon.

Today the Lunar Reconnaissance Orbiter (LRO) science team released a spectacular oblique image of Giordano Bruno crater. The image on the right is cropped and very significantly reduced to post here. It looks across the crater, with the near rim across the bottom of the picture and the wall of the far rim filling the photograph’s top half.

That wall is what makes this image cool. It is a cliff about 10,000 feet high, equaling almost two miles. Moreover, at its base is a now-solidified melt pool left over from the impact that made the crater.

Faster than a speeding bullet – or rather ten times faster than a speeding bullet – is a good starting point in terms of grasping the energy released in a typical impact event. That is, for a bullet approaching 2 kilometers in diameter! The pressure and heat that were released during the collision not only excavated a hole much larger than the impactor but also melted a tremendous amount the target rock. Melt was sprayed and sloshed on the forming crater walls where much of it flowed back, seeking the lowest point in the impact crater. From the LROC vantage point you can follow the path taken by impact melt as it flowed across the irregular floor, ponding in closed depressions, and some of it ultimately reaching the lowest point.

Below the fold is a much higher resolution section of this photograph, focused on the crater wall and the melt pool. I have still been forced to reduce the resolution somewhat to post it here. Along that cliff wall can be seen partial avalanches (the dark splotch near the center) as well boulder tracks with the boulders (probably larger than most houses) still visible as white spots at the wall’s base.

The scale here is difficult to imagine. This cliff wall is three times as high as The Abyss, the steepest single drop viewpoint along the south rim of the Grand Canyon.
» Read more

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Update on Europe’s Galileo GPS-type constellation failure

Link here. Key quote:

A new source has told Inside GNSS that the ongoing Galileo outage “…has to do with the Precise Time Facility (PTF), a redundant facility present in both Italian and German control centers.” This is the second source close to the program who has identified the PTF as the focus of the incident. Our source adds, “Incidentally, the redundancy apparently did not work.” So, the suggestion is that both PTFs, at two separate European locations, have failed. And, our source adds, “Take into account that the two major outages in the last two years were also caused by problems in the PTF. There are major architectural problems within the GMS [Galileo Mission Segment] under Thales Alenia Space…responsibility.” [emphasis mine]

The article does not go into any details how it is possible for two redundant facilities to fail at the same time. It does note however that while the U.S.’s GPS, Russia’s Glonass, and China’s Beidou systems all are operated by the military, which takes very seriously security, Europe’s Galileo is not.

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Chandrayaan-2 launch scrub caused by leak in helium bottle

Engineers today announced that the July 14 scrub of India’s Chandrayaan-2 lunar orbiter/lander/rover was caused by a leak in a helium bottle in the GSLV rocket.

“The good news is that we can fix the leak without dismantling the rocket, since there is an access door to the gas bottle which is atop the oxygen tank,” a senior scientist told TOI. “The bad news is that unless we ascertain the reason for the leak, there is a probability of the problem recurring.” Not having to dismantle means Chandrayaan-2 may be able to fly before the end of the July launch window, but a final failure analysis will be available only in a day or two.

Sources told TOI that the leak wasn’t serious enough to impair the flight, but Isro decided to apply “abundant caution,” given the importance of the Rs 978-crore project that would make India only the fourth country – after the US, Russia and China – to land a craft on the lunar surface.

I am willing to bet that if their investigation does not pinpoint the cause of the leak in the next few days, they will stand down from the July launch window. This mission, as well as proving the reliability of their GSLV rocket, are both too important to risk on an unknown and unsolved engineering issue.

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SpaceX pinpoints cause of Dragon explosion during test

SpaceX today revealed that it has pinpointed the cause of the explosion that destroyed a Dragon manned capsule during an engine test in April.

The company believes that the problem originated with the Crew Dragon’s emergency abort system, which consists of a series of small thrusters embedded within the capsule. If all goes well during a mission, these tiny thrusters are never really meant to be used. But if there is some kind of failure during a future launch, the thrusters can ignite and carry the Crew Dragon safely away from a disintegrating rocket.

SpaceX says that a leaky valve caused the propellant needed for these thrusters to cross into another system — one of really high pressure. When this contamination occurred, the high forces slammed the liquid around, causing valuable components to fail and leading to the ultimate loss of the capsule.

Koenigsman said that this contamination definitely was not anticipated, though the kind of valve that leaked has been known to have some internal leakage problem. Ultimately, he acknowledged that, to some extent, this was a design issue. “It’s something that the components should not have done,” Koenigsman said. “But at the same time, we learned a very valuable lesson on something going forward, one that makes the Crew Dragon a safer vehicle.”
““it was a huge gift for us.” ”

SpaceX will replace all of these types of valves with another component known as a burst disk, which is supposed to be much more reliable, according to Koenigsman.

The company is still hoping to fly before the end of the year, but admits that this may not be possible. Right now they have a tentative launch date in November.

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Hayabusa-2: Carbon-rich asteroids too delicate to reach Earth surface

New data from Hayabusa-2 has confirmed the long-held suspicions of astronomers that the reason they find so few fragments of C-class asteroids, such as Ryugu, on Earth is because they are too delicate to reach the Earth’s surface.

Ryugu and other asteroids of the common ‘C-class’ [chondritic] consist of more porous material than was previously thought. Small fragments of their material are therefore too fragile to survive entry into the atmosphere in the event of a collision with Earth.

…Until now, only a few chondritic meteorites found on Earth have been identified as fragments of C-type asteroids, which are very common in the Solar System (‘C’ is the chemical symbol for the element carbon). …”We can now confirm that fragments of these asteroids are very likely to break up further when they enter Earth’s atmosphere, and then usually burn up completely. This means that only the largest fragments reach the Earth’s surface,” explains Grott. “That is why meteorites from this type of asteroid are so rarely found on Earth.”

The good news is that, because of this, Earth’s atmosphere offers increased protection from C-type asteroids, which account for 75 percent of all asteroids. …However, further research is necessary to determine the maximum asteroid size for which this atmospheric protection is effective.

It is likely that even the largest rubble-pile C-asteroids will not pose much risk. Even if some pieces reach the Earth’s surface they are probably going to be small and unable to do much harm.

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Europe’s GPS-type constellation Galileo down

For as yet unexplained reasons, Europe’s entire Galileo constellation of GPS-type satellites has been out-of-operation for the past four days.

The European GNSS Agency (GSA), the organization in charge of Galileo, has not published any information in regards to the root of the outage, which began four days ago, on Thursday, July 11. On that day, the GSA published an advisory on its website alerting companies and government agencies employing the Galileo system that satellite signals have degraded and they “may not be available nor meet the minimum performance levels.” The agency warned that the Galileo system “should be employed at users’ own risk.”

The GSA published a more dire warning on Saturday, July 13, when it said that Galileo was experiencing a full-service outage and that “signals are not to be used.”

I cannot imagine any technical problem on the satellites themselves that would cause them all to fail at the same time. Instead, this appears to be some form of sabotage, a variation of the recent Russian tactic of disrupting GPS in areas they consider sensitive.

It also may explain the announcement yesterday by French president Macron that France is going to create its own space command.

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Russia successfully launches Spektr-RG carrying two X-ray space telescopes

Russia today successfully used its Proton rocket to launch Spektr-RG, carrying two X-ray space telescopes.

Spektr-RG was first conceived in the 1990s, but got shelved then because Russia did not have the money to launch it. The project got revived in 2005 when the Germans came on to build one of the two telescopes.

“We had an ambitious plan for the project which didn’t correspond to the power of the country of that moment,” [lead scientist Mikhail] Pavlinsky told Spaceflight Now. “We decided to restart it with a smaller version.”

The Russian and German space agencies signed an agreement in 2009 to jointly develop the Spektr-RG mission, but the project faced additional schedule delays due to technical problems and a decision to switch the observatory from a Zenit launcher to a Proton rocket.

Designers also changed Spektr-RG’s observing location from an orbit around Earth to a looping trajectory around the L2 Lagrange point.

Spektr-RG is the largest Russian astronomy satellite to launch since the Spektr-R radio observatory in 2011. Spektr-R stopped responding to commands from the ground in January after exceeding its planned five-year mission lifetime, and Russian officials declared the mission over in April.

Spektr-RG’s planned mission is set for seven years.

The leaders in the 2019 launch race:

9 China
8 SpaceX
8 Russia
5 Europe (Arianespace)

The U.S. continues to lead China in the national rankings 14 to 9.

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Mars Reconnaissance Orbiter image of Curiosity

Curiosity as seen from orbit

The Mars Reconnaissance Orbiter (MRO) science team today released an image taken on May 31, 2019 by the orbiter’s HiRISE high resolution camera of Curiosity when it was nestled against the cliff at the bottom of Vera Rubin Ridge.

The image above is that enhanced color image, reduced and annotated to post here. I have added the track of Curiosity’s route down from Vera Rubin Ridge leading up to the point where this picture was snapped.

In the image, Curiosity appears as a bluish speck. Vera Rubin Ridge cuts across the scene north of the rover, while a dark patch of sand lies to the northeast.

Look carefully at the inset image, and you can make out what it is likely Curiosity’s “head,” technically known as the remote sensing mast. A bright spot appears in the upper-left corner of the rover. At the time this image was acquired, the rover was facing 65 degrees counterclockwise from north, which would put the mast in about the right location to produce this bright spot.

Mirror-like reflections off smooth surfaces show up as especially bright spots in HiRISE images. For the camera to see these reflections on the rover, the Sun and MRO need to be in just the right locations. This enhanced-color image of Curiosity shows three or four distinct bright spots that are likely such reflections.

From this location Curiosity first continued along the cliff’s base to study that dark patch of sand to the northeast, then it turned almost due south in order to get back to its nominal route into Gediz Valles canyon, as shown in my May 30, 2019 rover update.

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Hayabusa-2’s second touchdown sample grab

Hayabusa touchdown sequence

The Hayabusa-2 science team yesterday released a series of close-up images taken just as the spacecraft touched down and then backed off from the surface of Ryugu.

I have cropped and annotated that sequence and placed all three images side-by-side above. The red arrows in the first two images highlight similar shadows in both pictures, with the appearance of dust visible in the lower center of the middle touchdown picture. I have not marked any comparable surface features in the third image because the uplift of material makes it too difficult.

That uplift however is exactly what the Hayabusa-2 science team needs, as it is some of this material that has hopefully been captured. Their fear was that this uplift posed a risk to the spacecraft itself, but they took precautions to minimize the risk and it appears that these precautions have worked.

We now must wait until the samples come back to Earth in December 2020 to see exactly what they caught.

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Major management shake-up at NASA’s manned program

NASA today did a major shake-up in its manned program, most specifically relating to the management of its SLS/Orion program.

In a major shakeup at NASA Headquarters, agency Administrator Jim Bridenstine said Wednesday that Bill Gerstenmaier, the widely respected director of human spaceflight, has been replaced in the midst of an ambitious push to meet the Trump administration’s directive to send astronauts back to the moon within five years.

Effective immediately, Bridenstine wrote in a letter to agency employees, Ken Bowersox, a five-flight shuttle veteran, space station astronaut and Gerstenmaier’s deputy, will take over on an acting basis while Gerstenmaier serves as “special advisor” to NASA Deputy Administrator Jim Morhard.

…Bill Hill, deputy associate administrator for Exploration Systems Development within HEO also has been replaced. A long-time NASA veteran, Hill helped manage development of the agency’s new heavy lift rocket, the Space Launch System, or SLS, needed to carry astronauts back to the moon.

While the long delays and cost overruns at both SLS and Orion can partly be blamed on micromanagement by Congress and a lack of interest by the previous Obama administration, the internal management by Gersternmaier and Hill during this time is also at fault. They have allowed these programs to drag on, and were in charge when numerous major screw ups occurred, from badly built test stands that went overbudget to dishonest budget manipulations to cracks in the first Orion capsule to contamination in SLS’s rocket engines to the dropping of an SLS oxygen tank to brittle and weak welds in those tanks to establishing an overall slow motion pace for construction of the entire project.

I suspect that this shake-up is linked to the story earlier this week where NASA hinted it was going to have to delay the first SLS launch for another year.

I wrote then that the Trump administration would not take kindly to such a new delay, even if it was justified so the agency could do a required full stack static fire test of SLS’s core stage. I am willing to bet that this shake-up occurred because Gertenmaier and Hill had finally revealed the need for this delay, and the shake-up was the Trump administration’s response.

This doesn’t mean that SLS won’t be delayed. It just means the Trump administration has decided it was time to put new people in charge.

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