Tag: spaceflight

Philae is go for separation, despite problem

12:25 am

Engineers have given a go for the separation of the Philae lander from Rosetta, despite the failure of a thruster to operate.

During checks on the lander’s health, it was discovered that the active descent system, which provides a thrust upwards to avoid rebound at the moment of touchdown, cannot be activated.

At touchdown, landing gear will absorb the forces of the landing while ice screws in each of the probe’s feet and a harpoon system will lock Philae to the surface. At the same time, the thruster on top of the lander is supposed to push it down to counteract the impulse of the harpoon imparted in the opposite direction. “The cold gas thruster on top of the lander does not appear to be working so we will have to rely fully on the harpoons at touchdown,”says Stephan Ulamec, Philae Lander Manager at the DLR German Aerospace Center. “We’ll need some luck not to land on a boulder or a steep slope.”

Update: Separation has occurred and signal reacquired from Philae. We wait for landing.

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Close-up image of Philae’s landing site

9:32 am


Agilkia landing site for Philae

Inset of landing site

In the preparation to Wednesday’s landing of Philae on Comet 67P/C-G, Rosetta’s science team has released a great image of the landing site, shown above. To the right is a higher resolution inset of the site itself, with the smallest object visible about 8.5 feet across.

Looking at this inset, there are some obvious worries that we all should be aware of prior to the landing attempt. Though the Agilkia landing site is generally more smooth than most of the comet’s surface, it still has significant hazards. The lower part is strewn with boulders and rocks, many of which are quite large. Any one of these could do serious harm to Philae should it land on them.

Even more interesting is the upper part of the landing site. Though very smooth, the image suggests to me that this is a very thick pile of softly packed material. Philae might land there and quickly sink below the surface, where its cameras will be able to see nothing.

Nonetheless, the science team has also released this outline of Philae’s science timeline after landing. The lander will also be taking images of both Rosetta and the comet during its descent, so even if the landing is a failure we will still get some worthwhile data.

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Comet Siding Spring’s fly-by of Mars changed the planet’s atmosphere

8:57 am

Data obtained by the various Mars orbiters during the close fly-by of Comet Siding Spring of Mars has revealed that the comet created a new temporary layer in the planet’s atmosphere.

The European Space Agency’s Mars Express spacecraft detected an increase in electrons in Mars’ upper atmosphere, partly ionising it. This was attributed to fine cometary dust penetrating the atmosphere, which led to a meteor storm of thousands of meteors per hour. The increase in electrons led to the creation of a temporary new layer of charged particles in the ionosphere, which runs from an altitude of 120 kilometres to several hundred kilometres above. This is the first time such an event has been seen, even on Earth the extra density of electrons was measured to be five to ten times higher than normal by NASA’s Mars Reconnaissance Orbiter. Another NASA spacecraft, MAVEN, which also observed the new layer in the ionosphere, will monitor for any long-term events as it goes about its regular duties of studying Mars’ atmosphere.

MAVEN’s Imaging Ultraviolet Spectrograph was able to ascertain the species of ions that flooded into the ionosphere from the comet, the first time a comet that has come direct from the distant Oort Cloud has been sampled in this way. It detected the signal of magnesium, iron and sodium ions following the meteor shower, a signal that dominated Mars’ ultraviolet spectrum for hours afterwards, taking two days to dissipate.

The chemistry that MAVEN detected appears superficially somewhat similar to the chemistry that Rosetta is detecting at Comet 67P/C-G, though there are differences.

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China’s struggle to compete with SpaceX

8:41 am

This Aviation Week story provides a detailed update on China’s effort to build a new family of Long March rockets that are less expensive to operate and can effectively compete with SpaceX.

Two main take-aways from the article. First, the first flight of the Long March 7, a direct competitor with the Falcon 9, has been seriously delayed. Originally expected to fly in 2013, that first flight has apparently been pushed back to 2015.

Second, even with extensive cost savings, the Long March 7 will still cost a customer more than a Falcon 9, $70 million vs $61 million.

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Alternative rockets and 2015 launch dates for Cygnus

8:54 am

The heat of competition: Orbital Sciences has pinpointed available launch slots and alternative rockets for getting Cygnus into orbit in 2015.

[Orbital CEO David] Thompson said Wednesday the company has narrowed its options to three launch providers which have openings as early as the second quarter — between April 1 and June 30 — of next year. Two of the launch providers are based in the United States. Orbital could also launch Cygnus missions with a European-based company, Thompson said. The contractors under consideration are presumably United Launch Alliance, SpaceX and Arianespace.

Unlike Virgin Galactic’s claims in my previous post, I find Thompson’s prediction here quite likely. His main problem is not technical but political. He has to convince his competitors to help him, and this story is his first shot across the bow in that negotiation. By making these facts public, Thompson applies pressure on these other companies to agree. And though the request is unstated, he is also enlisting NASA’s aid, since the agency is certain to back him in this negotiation and apply its clout in his favor.

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Virgin Galactic vows to fly again by April

8:34 am

The heat of competition: During a press tour of its Mojave facilities this week Virgin Galactic’s CEO revealed that the company expects to begin flying its replacement to SpaceShipTwo by April.

George Whitesides, the company’s chief executive, said construction of the second spaceship is already 65 per cent complete. Like its doomed predecessor, Enterprise, the new spaceship’s name is a tribute to both Nasa and Star Trek. It will be called SS Voyager, the Sunday Times reports.

Whitesides also said that LauncherOne, designed to put very small payloads into orbit, is 18 months away from its first flight.

I hope this predictions are true, but coming from Virgin Galactic I think I can be forgiven if I am very skeptical. Nonetheless, in referring to the new ship I will make it a policy to call it Voyager from here on out to distinguish it from the first ship.

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Bringing Dream Chaser home

9:47 am

The competition heats up: At an space industry conference this week Sierra Nevada outlined the ability of Dream Chaser to land at almost any airport, including the many financial and safety advantages of that flexibility.

The story notes that because Dream Chaser would not need an unusually long runway, it could land at most airports. Also, because it would have no hazardous materials on board, removing it from the runway after landing would be simple and straightforward. You would simply tow it away. The biggest advantage of this, howevr, is that if the spacecraft was docked at ISS and there was an emergency that required immediate evacuation, bringing Dream Chaser and its passengers home to a runway will be possible any time.

This presentation is part of Sierra Nevada’s sales effort to find new backers for their spacecraft, now that NASA has begged out. I think they make a good sales pitch. I hope someone with money agrees.

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The November 12 timeline of events for Philae’s landing on a comet

10:16 am

ESA has released a detailed timeline of events on November 11-12, when Rosetta’s Philae lander will be released and land on Comet 67P/C-G. They have also released a much more readable summary of the most critical events, describing what will be happening.

For Americans, these events will be occurring from around 3 pm (Eastern) November 11, when the process begins, to 12 pm (Eastern) November 12, when Philae will send back the first signals after landing. Much of the most critical events will take place in the wee hours of the morning.

Meanwhile, one of Rosetta’s instruments has confirmed the presence of water vapor and carbon dioxide in the jets seen near the comet’s narrow neck.

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Orion heat shield redesigned before its launch?

9:59 am

Even before Orion’s first flight next month to test its heat shield, engineers are proposing a major change in the shield’s design and manufacture.

The Orion heat shield’s titanium skeleton and carbon fiber skin was fabricated by Lockheed Martin — the craft’s prime contractor — in Colorado. The skeleton was shipped to Textron Defense Systems in Massachusetts for installation of a fiberglass-phenolic honeycomb structure. More than 330,000 individual cells make up the honeycomb, and Textron technicians — using a special dispensing gun — filled the cells by hand with a material called Avcoat. The Avcoat insulation is supposed to ablate away during the Orion spacecraft’s re-entry, protecting the underlying structure from searing temperatures. The Apollo moon capsule used the same type of manually-applied material for its heat shield, and it worked so well Lockheed Martin and NASA decided to dust off the design.

Engineers scaled up the heat shield for the Orion crew capsule, which is about four feet wider at its base than the Apollo command module. “That’s what worked for Apollo, and that’s what we’ll work with for this mission,” Bray said, referring to the EFT-1 launch in December.

But a review of the heat shield on the Orion spacecraft set for launch Dec. 4 revealed the Avcoat was slightly more uneven than expected, according to Jim Bray, crew module director at Lockheed Martin, Orion’s prime contractor.

It also appears that it is too expensive to build the shield by hand, as it was done during Apollo. Instead, they intend to build future heat shields as single blocks assembled not by hand but by machine.

This is another example of why SLS/Orion is an incredible money black hole. What is the point of next month’s test flight of the heat shield if the shield they are testing is not going to be used on future flights?

Meanwhile, the press (apparently ignorant and uninformed about this subject and brainwashed by a NASA Orion press event) is filled with numerous stories claiming that this test flight is NASA’s first step to getting to Mars. What hogwash.

I especially like this quote from the space.com article:

On Dec. 4, NASA officials are expected to launch the Orion spacecraft on its first test flight, putting the capsule through its paces in space before it splashes down in the Pacific Ocean. The goal of the flight is to see how some key Orion systems — like its huge heat shield and parachutes — work before launching humans into deep space sometime in the future. [emphasis mine]

Yet, most of the heat shield test data obtained by this test flight will be worthless and inapplicable to future Orion capsules. In other words, this test flight is, as I said, hogwash, a public relations stunt to sell Orion to Congress and to uneducated reporters. It is also an enormous waste of taxpayer money and the limited resources NASA has.

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Solid rocket motors for American rockets?

9:34 am

The competition heats up: Even as ULA and Blue Origin begin work building an American engine to replace the Russian engines on the Atlas 5 rocket, ATK is offering its solid rocket motors for both Atlas 5 as well as Antares.

The company’s sales pitch is that they can get their product ready faster and cheaper. And since they are merging with Orbital Sciences anyway, I will not be at all surprised if Antares ends up with ATK solid rocket motors for its first stage.

As for Atlas 5, this sales pitch is actually aimed at Congress, which could step in and force ULA to buy ATK motors instead of Blue Origin’s new engine, even if this switch is against the wishes of ULA. As foolish as this might seem, the politics of pork (ATK provides more jobs than Blue Origin) could make it happen.

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A pause in investment commitment to Virgin Galactic

9:19 am

The heat of competition: Virgin Galactic’s Arab investors have decided to hold off further commitment to the project until the investigation of the SpaceShipTwo crash is completed.

The backing of deep-pocketed Aabar Investments, run by the Abu Dhabi government, may be crucial to Virgin Galactic as it struggles to recover from the accident, which killed one test pilot and left another seriously injured. “As an investor, Aabar is concerned of course. It is a challenge – nothing can be decided until investigations are over,” the source said, declining to be named because of the sensitivity of the subject. “For now, it is a wait-and-watch situation.” Asked if Aabar was still committed to Virgin Galactic, the source said only: “There is time to make an assessment of the future strategy.”

This is hardly a surprise. Nor does it guarantee an end to Richard Branson’s company. What it signals is a recognition that Virgin Galactic has had a serious problem and must demonstrate that it can fix that problem before it will regain the trust of its investors.

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Second SpaceShipTwo almost ready for flight

8:32 am

The heat of competition: Virgin Galactic today released hanger photos of the almost finished second SpaceShipTwo.

Even as the investigation into the fatal breakup of Virgin Galactic’s SpaceShipTwo rocket plane continues in Mojave, California, the next SpaceShipTwo is more than halfway complete in a Mojave hangar — and is expected to start going through tests on the ground and in the air next year.

Virgin Galactic’s manufacturing subsidiary, The Spaceship Company, has been working on the plane for two and a half years. It’s variously known as SpaceShipTwo Tail No. 2 or N202VG, and it’s part of Virgin Galactic plan to have a fleet of five SpaceShipTwo rocket planes and two WhiteKnightTwo carrier planes.

This story is a great example of the public relations genius of Richard Branson. Even with the pieces of SpaceShipTwo still being picked up on the ground he finds a way to sell his company positively to the world. They not only intend to continue their effort, they have the ship to prove it!

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Turbopump failure in first stage engine eyed for the Antares launch failure

8:14 am

The investigation into the launch failure of the Antares rocket one week ago is now focusing on the turbopump in one of the rocket’s first stage engines.

“The Investigation Board (AIB) is making good progress in determining the primary cause of last week’s failure. A preliminary review of telemetry and video data has been conducted and substantial debris from the Antares rocket and its Cygnus payload has been collected and examined,” noted Orbital on Wednesday. “While the work of the AIB continues, preliminary evidence and analysis conducted to date points to a probable turbopump-related failure in one of the two Aerojet Rocketdyne AJ26 stage one main engines. As a result, the use of these engines for the Antares vehicle likely will be discontinued.”

It was later noted that the AJ-26 could still be used if they were proven to be completely flight-worthy.

If Orbital Sciences decides to completely cease using the Russian engines, it could mean a very significant delay before they can launch again, maybe several years. If they do that, I expect them to face contract penalties from NASA for the failure to deliver cargo to ISS on a reasonable schedule. It will also mean that their chances of winning a second contract will go down significantly.

They need to replace the engine, but they also need to keep launching. The article as well as a company press release today describes how they are exploring other launch vehicles, including the Falcon 9, to launch Cygnus, but I see no reason for them to completely abandon the Russian engines immediately. What they need to do is find what failed, fix it in the remaining engines, and keep flying while they scramble hard to replace the engine entirely.

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A geological score for Curiosity!

10:25 pm

Spectroscopy from Curiosity’s most recent drilling has been found to match and thus confirm the spectroscopy of the same spot taken years ago from orbit.

In observations reported in 2010, before selection of Curiosity’s landing site, a mineral-mapping instrument on NASA’s Mars Reconnaissance Orbiter provided evidence of hematite in the geological unit that includes the Pahrump Hills outcrop. The landing site is inside Gale Crater, an impact basin about 96 miles (154 kilometers) in diameter with the layered Mount Sharp rising about three miles (five kilometers) high in the center.

“We’ve reached the part of the crater where we have the mineralogical information that was important in selection of Gale Crater as the landing site,” said Ralph Milliken of Brown University, Providence, Rhode Island. He is a member of Curiosity’s science team and was lead author of that 2010 report in Geophysical Research Letters identifying minerals based on observations of lower Mount Sharp by the orbiter’s Compact Reconnaissance Imaging Spectrometer for Mars (CRISM). “We’re now on a path where the orbital data can help us predict what minerals we’ll find and make good choices about where to drill. Analyses like these will help us place rover-scale observations into the broader geologic history of Gale that we see from orbital data.”

This is a significant finding. Not only does this data now prove that the orbital data is correct, it demonstrates that scientists can now use that orbital data to direct Curiosity to even more interesting geological surface features. In fact, this ground-based data will help them calibrate all their orbital data more precisely, thus making our geological knowledge of Mars more accurate and reliable.

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Update on SpaceShipTwo investigation

8:20 am

Additional details about the investigation into the crash of SpaceShipTwo have now been released.

The investigators are focusing on the telemetry that the pilots were receiving, as well as the system for activating the ship’s braking feathering system.

As I have noted in the comments, we must try not to speculate on this subject, especially because this issue could do harm to innocent people. For example, some reports have incorrectly attributed the crash to pilot error. To say this now is false. All the investigation has noted is that the co-pilot took the first step to activating the feathering system, as he was supposed to do, though slightly early. The feathering system then deployed on its own, without the second command being given.

We do not yet know the finer details that make his action significant, or not. This is why the investigation is checking into the telemetry the pilots were getting, which might have affected when they did what they did.

We need to wait for more data.

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Some Virgin Galactic customers demand money back

5:22 pm

News reports suggest that — following last week’s SpaceShipTwo crash — more than thirty of the seven hundred people who placed deposits with Virgin Galactic to fly on SpaceshipTwo have pulled out, demanding their money back.

In response to the claim that more than 30 customers are considering their position in the aftermath of the crash, a spokesperson for Virgin Galactic admitted a number of people have asked for their money back. “We can confirm that less than three per cent of people have requested refunds,” the spokesman said.

This is not a surprise, nor should it be. A company can only survive a crisis like this by responding honestly, quickly, and directly. If Virgin Galactic does this, finding the cause of the crash and fixing it, they will likely hold onto most of their customers. If they don’t, those remaining customers will leave. This week’s cancellations are the first immediate response to the crash. The future of the company, however, will be determined by what happens in the next six months.

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SpaceShipTwo’s engine did not cause failure

8:39 am

The investigation into the failure of SpaceShipTwo last week during a powered flight test has determined that the accident was not caused by the spaceship’s engine and that the spaceship’s feathering system for return to Earth began deploying early during powered flight.

The ship’s fuel tanks and its engine were recovered intact, indicating there was no explosion. “They showed no signs of burn-through, no signs of being breached,” Christopher Hart, acting chairman of the National Transportation and Safety Board, told reporters at the Mojave Air and Space Port in Mojave, Calif

Instead, data and video relayed from the ship show its hallmark safety feature — a foldable tail section designed for easy re-entry into the atmosphere from space — was deployed early.

More here. Deployment required two commands, activation and then deployment. Data shows that the co-pilot Michael Alsbury activated the system slightly early. The second command, however, was not given, but the feathering system began to deploy nonetheless, during powered flight when the ship was accelerating upward. That is when the ship broke up.

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SpaceShipTwo accident pilots identified

9:36 pm

As the National Transportation Safety Board (NTSB) begins its investigation into the SpaceShipTwo test flight failure, the identities of the two pilots have finally been released.

The Kern County Coroner’s Office announced Nov. 1 that Michael Alsbury, a 39-year-old test pilot employed by Scaled Composites, was the person killed in the crash of the vehicle north of Mojave, California. Scaled Composites confirmed that identification in a press release issued late Nov. 1, which also stated that the pilot injured in the crash was the company’s director of flight operations, Peter Siebold. Alsbury was the co-pilot of SpaceShipTwo on its first powered flight, in April 2013. According to public flight logs maintained by Scaled Composites, he most recently flew SpaceShipTwo as co-pilot on an unpowered test flight on Aug. 28, a “cold flow” test where nitrous oxide was vented through the engine but not ignited.

Siebold was the pilot or co-pilot of SpaceShipTwo on its previous four flights, including the Aug. 28 flight with Alsbury. Siebold was also a pilot on several test flights of SpaceShipOne, an earlier suborbital spaceplane developed by Scaled Composites that won the $10-million Ansari X Prize in 2004. In the statement, Scaled Composites said that Siebold was “alert and talking with his family and doctors,” but provided no other details about his condition.

Alsbury should receive the same honor given to all other astronauts and pilots who have sacrificed their lives so that humans will someday leave the surface of the Earth.

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New rocket coming from ULA?

12:45 pm

The competition heats up: The head of ULA hints that the company is developing a new rocket.

“Today, we have Atlas and Delta,” Bruno said of ULA’s product line. The company is completing studies leading to an announcement early next year of “what we will have next.” He confirmed, “It could be a new rocket.”

It could be that they have seen the writing on the wall and realize that Atlas and Delta are simply too expensive to compete with SpaceX and have decided they need to come up with something better. I hope so.

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Rosetta gets in position to release Phalae

9:36 am

Rosetta has successfully maneuvered into position prior to releasing Philae on November 12 for landing on Comet 67P/C-G.

The thruster burn took place starting at 02:09:55 UTC (03:09:55 CET), ran for 90 seconds and, based on an initial analysis of spacecraft radiometric data, delivered a delta-v – change in speed – of 9.3 cm/sec, as confirmed by the Rosetta Flight Dynamics team. It was the second and final of two ‘deterministic’ (i.e. direction and thrust are prepared in advance) manoeuvres that moved Rosetta onto the planned lander delivery orbit, now at a height of about 30 km, which will be maintained right up until the pre-delivery manoeuvre at two hours before separation at 08:35 UTC (09:35 CET) on the morning of 12 November.

…[T]he next planned orbit-changing manoeuvres will occur on the 12th at (a) 2 hours before separation and (b) about 40 minutes after, in between which Philae will be released. The pre-delivery manoeuvre will shift Rosetta’s trajectory so that the orbiter would be on a path so as to pass over the comet at a distance of 5 km, while the separation will occur at 08:35 UTC on board the spacecraft about 22 km (the confirmation signal will arrive on Earth at 09:03 UTC).

Since Philae is a passive lander, firing no thrusters but simply being thrown gently at the comet by Rosetta, the last two burns are crucial. The first literally puts Rosetta on the same collision course as Philae so that when the lander is released it is on a course to hit the comet. The second takes Rosetta out of that collision course, since no one wants it to hit the comet also.

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“The sky is crying.”

9:19 am

Words from Mohave.

Friday began bright and sunny, a day full of promise that quickly brought tragedy. As I write this early on Saturday, a cold hard rain is lashing at my windows. That’s a good thing. We need it.

And it feels right. The sky is crying, adding to an ocean of tears shed here today.

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