Monday, June 18, 2007
---ISS Fixed
Spaceflight Now | STS-117 Shuttle Report | Station computers brought to life after impromptu repair
Spaceflight Now | STS-117 Shuttle Report | Two more space station computers revived
Cosmic Log : Obsolete chips in space
ESA Microelectronics page
tsc691e.pdf (application/pdf Object)
In another .22LR-in-the-fusebox save, Russians on the ISS bypassed faulty surge-suppression switches on the power supplies of the malfunctioning flight control computers, and got them to reboot and run. Further testing showed that the critical control functions were performing properly. The switches may have been affected by power changes when the new U.S. solar arrays were connected. Of course, the surge-protection capacity of some pieces of wire is pretty much negligible.
Alan Boyle's weblog at MSNBC has some interesting details about the command-and-control computers used by the Russians. They are a radiation-hardened Sparc v7 design, circa 1987. From the ESA documentation, they couldn't even put the CPU on a single chip at the point of deployment (they managed it later), but the computing “core” is on three separate chips. They do have tri-state outputs. Problems I can find include floating point errors, a tendency for bits loaded into the registers to cause adjacent bits to flip values, and lockups in the fault-handling registers. It might be interesting to compare them to computers in use in “fly-by-wire” aircraft systems.
Memories....my flight hardware experience included an EVA systems battery charger which used an Intel automotive ABS processor to “reprogram” the output from the 6502 (predating the 6510's in the Commodore 64's in the bottom of my closet) installed in an early-'80's-vintage commercial charger, and a respiratory mass spectrometer which was “controlled” by an “analog computer”---essentially a pile of often-mutually-contradictory op-amps which were essentially impossible to calibrate all at the same time. An astonishing percentage of “spaceflight hardware” is dirty, poorly maintained, mismanaged, obsolete junk.
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Friday, June 15, 2007
---Ruth Graham
My Way News - Billy Graham's Wife Ruth Dies at 87
Team-mate in one of the most important Christian ministries of modern times, Ruth Graham died yesterday.
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Team-mate in one of the most important Christian ministries of modern times, Ruth Graham died yesterday.
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---ISS Computer Breakdown Continues
The Flame Trench space blog by Florida Today[posted by John Kelly at 11:23 AM]
Doesn't look good for theISS. The really bad news is that they unplugged the U.S. solar arrays, the suspected proximate cause of the problem, and it didn't go away.
News conference is upcoming on NASA TV.
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Doesn't look good for theISS. The really bad news is that they unplugged the U.S. solar arrays, the suspected proximate cause of the problem, and it didn't go away.
News conference is upcoming on NASA TV.
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Thursday, June 14, 2007
---ISS Computer Failure
SpaceThe Flame Trench space blog by Florida Today
Space station glitch puzzles the experts - Human Spaceflight - MSNBC.com[Oberg]]
All last night, engineers worked to figure out why ALL of the supposedly redundant control computers on the Russian part of the ISS suddenly failed as the new U.S. solar arrays came online. There was great relief this morning, as the Russians assured everyone that they were regaining control of some of the critical systems---which lasted for about 7 minutes, whereupon they all failed again. U.S. gyrodynes and the Shuttle’s thrusters are keeping the station oriented for now.
James Oberg, at MSNBC, fills in a lot of details about the systems, where they came from, how they are supposed to work, and what will happen if they can’t be fixed before the Shuttle has to leave.
The computers were made in Germany---at least they aren’t Russian---and operate in three sets of two pairs to provide redundancy. This is actually the second time something like this has happened. The last was in 2001, when all of the flight computers in the U.S. module inexplicably failed while the Shuttle was docked and stuff was being bolted on.
It’s clear is that the problem is very serious, and the optimism from managers and engineers on the ground---who assure everyone that they don’t see any reason yet to talk about having to abandon the station, perhaps permanently---is just beginning to ravel a little around the edges. Worse, if attitude control can’t be maintained after the Shuttle leaves, conditions could deteriorate to the point that the Soyuz might not be able to undock from a rapidly tumbling station.
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Wednesday, June 06, 2007
---63rd Anniversary of D-Day
FOXNews.com - Defense Secretary Pays Tribute to Fallen Troops in Normandy at 63rd Anniversary of D-Day
It was a miserably cold, damp, windy, overcast day in February, 2005. I remember the place as one of the loneliest stretches of coastline I've ever seen in person. It probably wasn't just because it was off-season, and we were virtually the only people in the entire cemetery. Despite the best intentions of generations, in the 63 years since the Longest Day we have made more places like this around the world, and there are more to come.
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Tuesday, June 05, 2007
---Cyclone Gonu Heads for Iran
It’ll be a wet day in....
My Way News - Cyclone Gonu's Winds Blast Oman Coast
Cyclone nears Persian Gulf oil supplies - Weather - MSNBC.com
TRCgonu156_MT.jpg (JPEG Image, 1280x1024 pixels)
...uh, well, Iran, for one. Tropical Cyclone Gonu weakened from Category 5/160mph to about Category2/106mph before it glanced off the coast of Oman today. There have been evacuations, but no reports yet of damage or injuries.
It is expected to weaken further to a tropical storm equivalent before it crosses the Gulf of Oman and makes landfall in southeastern Iran in the next few hours.
According to some sources (I’m still trying to find it in writing), Gonu is the first cyclone (=hurricane) ever known to enter the Gulf of Oman, and landfall of a cyclonic system in Iran is apparently also unprecedented in history.
It’s not clear whether the storm’s path will take it over the critical Straight of Hormuz. Many people in many places will be sweating through this event, since it is likely to adversely affect oil processing, loading, and shipping in the Gulf for a number of hours.
[Additional information, and a more accurate timeline from the AP:
My Way News - Thousands Evacuated Ahead of Cyclone
Gonu has taken a NW turn that is likely to make the Straight of Hormuz impassible to tanker traffic for the duration.]
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Monday, June 04, 2007
---In Space News
---Atlantis is scheduled to launch on an ISS assembly mission Friday, June 8.
FL Today: Space: "NASA lawyer in trouble for destroying DVDs"
From the Statement of Michael Wholley at House Hearing on NASA IG Investigation SpaceRef
“I concluded that these were not "records" for purposes of the FRA, but also concluded that if they were retained and filed they could become "records" by virtue of that retention. From my perspective, and as I stated to the subcommittee staff, I did not believe it wise to have these in any way become "records" subject to release under the Freedom of Information Act.”My experience with the NASA legal department (at JSC) has fully prepared me for this. I am familiar with this legal entity which hires its members for their automated wllingness to perform information control, rather than any sort of quick-wittedness or sensitivity to basic moral or---heaven forbid---ethical consideration, or concern for-- or vision of the future for that matter. They are so accustomed to receiving deferential treatment from the judiciary and uninformedness from the general public, as a government agency and major employer, that brains aren’t high on the legal hiring priority list.
I am in no way even slightly surprised, let alone stunned or horrified, to learn that a prominent member of the NASA legal group--- NASA General Counsel Michael C. Wholley---reached a legal determination, based on a few moments of “research” into the Federal Records Act and the Freedom of Information Act, that records of a meeting involving Administrator Griffin which contained potentially damaging information were “not records” yet, and that they could be safely and legally pounded into oblivion and permanent non record-ness with a board from his bookshelf.
I did, however, manage a brief sigh of resignation when I read his justification for this action:
“My bad...pure heart, empty head.”Well? How do you suppose he got his job, anyway? Is it ironic, as FLToday points out, that the records being destroyed involved a discussion about other troublesome records being destroyed? Sure. That’s sort of the problem here; I’m basically anesthetized to behavior from high-ranking NASA officials that would result in imprisonment or mandatory psychiatric care for anyone else but a former member of the Clinton administration.
The Flame Trench space blog by Florida Today:" NASA clears Atlantis' tank for rollout"
FL Today: Space: "Tank 'not pretty,' but should pass inspection"
The photos with this posting from the Flame Trench include my choice for the definitive snapshot of the whole hail-damage repair effort to get Atlantis’ ET ready for its June 8 flight: Two guys with something that looks oddly like a Brobdingnagian Gillette razor, shaving the damaged foam off the nose of the tank.
The response to this situation from NASA---expectation control: It won’t be “pretty”, but it will probably work.
The Flame Trench space blog by Florida Today:" NASA managers mull shuttle engine issue"
In the windup for the June 8 launch of Atlantis, engineers have flagged a potential corrosion problem with the bolts which hold some of the STS main engine turbopumps in their assembly. Putting some rather hysterical responses to the post aside, the issue has probably been handled as well as can be expected. The bolts on Atlantis have been checked for corrosion and cleared.
It does show a serious overall weakness in the long-term use of what is arguably history’s most complex man-made “machine”. If you have something with a million pieces in it, the million-to-one sequences of failure that usually bring about major catastrophes become all too significant.
FL Today Space: "Orbiters feel pains of aging"
Yep, it’s 2007, and the large composite-reinforced flight-weight pressure vessels used to pressurize the STS maneuvering propulsion systems are---wheeze---almost ten years past the best-of-luck extended certification given them when the expected ten-year service life expired, at which point (about 1998), no attempt at re-certification was made. NASA is dodging the problem by keeping non essential personnel away from the Shuttle on the pad, and keeping the pressure at 85% until the last moment before launch, in the hope that no one will be injured or killed if one of them “lets go”. What such an explosion would do if it occurred in flight is a matter of wishful thinking and crossed fingers---It probably won’t happen this time.
NASA addresses fears about space fire hazard - Human Spaceflight - [Oberg]MSNBC.com
Meanwhile, on the ISS, a fire hazard has been identified that could cause oxygen lines which supply the U.S. airlock to catch fire and possibly rupture, causing serious damage to the airlock and possibly injury to the crew inside it. The fire hazard stems from the possibility that metal debris left in the line from production or assembly could be propelled down the lines with enough force to strike the lining and ignite in the pure oxygen environment. Leaving aside for the moment the profound stupidity of manufacturing lines for oxygen service with potentially lethal debris in them, and then leaving them in service anyway, engineers had “worked around” the problem by limiting the flow rate through the lines to reduce the energy of any sparklers in the lines. Unfortunately, the geometry of some connections in the lines could cause flow to unpredictably exceed the speed limit. The “work around” for the “work around”? Operate the valves slowly....
Solar system sails sideways through galaxy - Space.com – MSNBC.com
Okay, I’m not sure I know what’s going on here. Apparently, analysis of the shape of our Sun’s heliosphere, the boundary between the solar wind and the surrounding galactic environment, shows that our system is traveling through the Milky Way (come on, guys, can we get a real galactic name, here?) almost sideways, its axis of rotation almost perpendicular to the galactic plane.
JPL Catalog Page for PIA09211:"Coasts and Drowned Mountains"
On its 31st pass by Saturn’s enigmatic moon Titan, Cassini obtained SAR images of what appears to be a complex coastline and island chains formed by mountains submerged in an organic sea.
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