Test before deployment ?
Or they moved to "Move fast and break things" DevOps paradigm and other stuff like that.
The Hubble Space Telescope resumed science operations this morning after a software error knocked the veteran spacecraft offline. In what sounds for all the world like an on-orbit Blue Screen of Death, a software update uploaded to the spacecraft attempted to write to a location in computer memory to which it didn't have …
That, plus it sounds like they may not have a test rig that reflects production on the Hubble....or if they do, adequate testing was not performed.
Still, sounds like they had sufficient contingency/resilience to enable a fix, which is impressive given the nature of the live environment.
Or tested it in a virtuous virtual environment, which lacked the virtue of being faithful to the physical environment.
Such as a failed patched environment that doesn't reflect what's actually in use. Muddle the testbed, back it out poorly, everybug passes after...
In the late 80's I worked briefly at Perkin-Elmer in Minneapolis.
A long commute for me but, it was one of the "cooler" places where I spent any time. They were building a lot of "neat stuff" (I thought), including some of the Hubble components.
Last I heard Perkin-Elmer has become "a shadow of it's former self"
Too bad if that's true.
Might be a good what-if exercise for NASA or SpaceX to work on; what would it take in terms of a combined Crew Dragon & Cargo Dragon mission to perform a possible next round of service on Hubble?
What kind of 3 or 4 port mission support docking module could be developed, quickly, to ease the task?
That would require some joined up thinking that appears to be way beyond most of the people they have around today.
Bluntly, there is no servicing capability and no sign of anything being put together that could remotely do a tenth of what the Shuttle could. All the focus has been on getting bigger lumps of stuff into space, not how we might usefully service and maintain them.
There is some work by ESA to refuel satellites with a standard interface but that is nothing compared to the handling capacity needed to actually maintain assets.
The costs and potential for things not working on James Webb are just mind-blowing. Yes, it is a sophisticated package but the knock-on of this extravagance is already being felt and will continue to do so for years. I would also be very surprised if it's functional life is anything approaching that of Hubble.
Moreover being at L2 it's beyond the reach of anything operative today - and beyond the Shuttle range too, of course.
Instead of designing propaganda missions I would have invested in broadening space operations beyond low orbit. It would also build the basis for longer range missions to the Moon and Mars. But that plan is not useful for political propaganda.
The Shuttle provided the capability for several EVAs - which means being able to store the EVA suits, and let astronauts exit and reenter several times. AFAIK the Dragon does not allow that.
Then the cargo bay of the Shuttle had the Canadian Arm to capture and keep the Hubble safe and steady while maintenance activities were performed and let easy access to all the replacement parts needed. Getting them out a Cargo Dragon while wearing EVA suits I don't believe is easy or even possible. Nor I believe the Cargo can be fitted with external devices for maintenance work and keep its re-entry capabilities. A separate platform with such devices would not be able to re-enter intact as well, and would be an expensive non re-usable one.
I don't remember if the Shuttle also powered the Hubble when it was not able to do it itself, to keep instruments safe. The Shuttle also could restore an higher orbit.
The Shuttle was an outstanding orbital workshop, and should have been used and kept operative for that task alone - the idea of using it as a launcher was stupid. Its real limitation was it could only reach low orbits.
Today whatever is not attached to the ISS can't be repaired in orbit.
You are expecting politicized bean counters to think constructively like engineers. That has never been known.
What does it cost? When do you want to spend it? Is it in the existing budgets? You have now exceeded the most constructive bean counter responses. Even "there is an exposure to even more costs if you do not spend this" is outside their cognitive capabilities.
Service life and service life costs - unrepaired and repaired should be part of the costings of every large item put into space. That also requires the design to allow in orbit repair and someone thinking ahead to what would need to be repaired then ensuring the designers considered that in the system designs. This would raise the ire of the bean counters on the large item projects and the arguments would be rehearsed again.
"A separate platform with such devices would not be able to re-enter intact as well, and would be an expensive non re-usable one."
?? Just leave it in orbit, obviously. Non re-enterable != non re-usable. Only people need to re-enter, plus whatever ship is needed to move people.
It would need maintenance as well, be able to move to the required device to be maintained, able to receive the spare parts and refueled. Not impossible, true, but probably even more complex than something that can return to earth.
Instead of a Cargo Dragon, probably something alike the X-37 would be more practical.
After quite a long day, and perhaps because rather more used to "space-probe success" news of late, I read that as "revealing a bunch of other galaxies".
Well, I thought, that *was* a fortuitous occurrence!
... but sadly not. But at least the old thing is still hanging in there...
The night was as black as the inside of a cat. It was the kind of night, you could believe, on which the gods moved men as though they were pawns on the chessboard of fate. In the middle of the elemental storm a fire gleamed among the dripping furze bushes like the madness in a weasel’s eye. It illuminated three hunched figures. As the cauldron bubbled an eldritch voice shrieked: ‘When shall we three meet again?’
There was a pause.
Finally another voice said in far more ordinary tones: ‘Well I can do next Tuesday.’
- Wyrd Sisters, Terry Pratchett
Pterry icon, El Reg?
This is one of the reasons we can't just discard the thousands of terrestrial telescopes just to accommodate Starlink, as some suggested here.
On earth a stuck barn door or some broken support modules would just require the janitor to grab a screwdriver and a ladder; In space it requires using some extremely expensive and currently unavailable transport, so you risk all the time to lose the totality of the telescope (and investment) just because of some malfunctioning .50 cents part you could had fixed down here with duct tape while waiting for a spare.
Space is big, and unlike SciFi movies tend to suggest, it's more than a "whoosh" and a "zoom" away.
On a much less exotic note, that is similar to an argument we used to put to suppliers in the early days of North Sea oil development. A compressor (say) in a normal factory could be fixed by a service engineer turning up in a white van; even local maintenance folk could fix things with spares arriving by van in a few hours. Not so easy on a platform 100 miles out in the N.Sea. Small parts could be sent out on the next helicopter (most likely the next days crew-change flight) but larger parts would need a separate chopper (expensive - though often a lot less than the cost of not repairing asap) or by boat (which would often be weekly). The lost production cost of breakdowns can be eye-watering!
Setting aside the spares issue, a service tech can't get on a chopper without appropriate certification (including medicals and survival training).
As I said, not as exotic as HST but the comment took me back.
As an aside (and off topic) I recall a dispute I had with a supplier of downhole pumps, regarding the limited testing given before delivery. The supplier happily replied that they would replace any faulty pump at no charge. I asked if that meant at their cost; we agreed to split the risk and forego back-charging lost production - but the cost of removing and reinstalling one of their pumps started at $2m. The supplier rep stuck to his guns. So did we, and switched supplier (to one that built a dedicated test rig) for future pumps. As the first supplier's pumps failed (the operator had already installed quite a number and the failure rate had triggered my involvement), they were replaced with the competitors...
The first Law of Support in any field. "If it ain't broke - don't fix it".
Someone once discovered - in passing - an obvious error in a payroll package. They fixed it - and payroll failed. There were actually two errors - whose effects cancelled each other out.
I spent a fair chunk of last Thursday fixing a collection of unit tests that had a similar problem. I removed a redundant class and suddenly found myself facing over a dozen test failures relating to code that I hadn't directly touched.
I was in a bad mood by the time I was done.
Working in an environment that can have problems like this one, better testing might have helped but it's no guarantee. I think that NASA did very well to actually find the issue and fix it. I've worked with NASA engineers in the past and it's always been fun, they see complex problems and fix them even if it takes the rest of us days to even figure out what might be the problem.
Cheers and Beers to NASA for keeping Hubble running!
While I agree that, unlike everywhere else, NASA decisions aren't taken by accounting department, given the price of Hubble (or other space probes) it is justified to have any amount of engineers spend the time necessary to find a good solution (as opposed to a quick/cheap one).
In any endeavour it is always wise to build in some fuzzy flexibility*** to allow some chance of fixing an unexpected problem. In the days when Crosby "Quality" courses were mandatory - that was usually called "over engineering" by our PHBs.
We called it "open-ended design" - which often became "here's one I made earlier" solutions for problems or enhancements.
***"In Search of Excellence" author Tom Peters described a successful collaboration between multiple suppliers - that had deliberately fuzzy interface definitions between their modules.
Since Hubble is widely believed to be a prototype for a line of inward-pointing spy telescopes, are all those worn out too ?
Actually, it is the other way round. NASA chose to use a 2.4 metre mirror in Hubble instead of the originally suggested 3 metre mirror as "changing to a 2.4-meter mirror would lessen fabrication costs by using manufacturing technologies developed for military spy satellites."
"A perfect 2.4 m mirror observing in the visual (i.e. at a wavelength of 500 nm) has a diffraction limited resolution of around 0.05 arcsec, which from an orbital altitude of 250 km corresponds to a ground sample distance of 0.06 m (6 cm, 2.4 inches). Operational resolution should be worse due to effects of the atmospheric turbulence."
The Keyhole satellite series predates Hubble by a decade or two. (Maybe more. But nobody's talking.) And they are regularly replaced, thanks to the bottomless funding pit of the NRO and other intelligence services.
If NASA was funded to the same degree, the JWST would not only have launched by now, we'd be on JWST number 5.
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