One thing he would point out, that I never see discussed, was that at the time they built the mirror, there was an expectation that it may not be perfect, on account of how the Earth's gravity would slightly deform the mirror during manufacturing. As he tells the story, they'd tried to factor that into the design, but had less confidence in it. This, of course, was not the reason for the eventual problems, but to illustrate that this kind of thing was understood.
The big picture of the failure relates to the Shuttle program as well. At the time Hubble was being developed, its mission was supposed to allow for a lot more around the "shuttle" aspect: not just that it could be reused, but that it could be reused in an actual shuttling capacity, like an orbital pickup truck. So it was supposed to be possible to bring the telescope up into orbit (away from gravitational stresses), see how it worked, and if necessary, bring it back down for corrections. Since the end result of the Shuttle design cut down significantly in its capabilities in this regard, the Hubble program was left without its "Plan B".
Also consider that the mirrors on James Webb space telescope need to account for both deformation from gravity when they are manufactured but also that they are manufactured at room temperature and will be operated at cryo temperatures. But JWST is also special since they have actuators to put stress on the mirror segments to be able to reshape them slightly on-orbit to focus.
(He also worked on the TEAL AMBER and TEAL BLUE satellite surveillance systems, and probably others that he never even talked about.)
Having gone to school in LA where, at the time, ALL of the EE jobs were in the Defense sector, I specifically moved up to the Bay Area to work on cool stuff I could actually talk about with others[1].
One thing of note is that ageism is MUCH less of an issue in jobs that require security clearances. So a number of engineers who are suddenly perceived as "too old" to contribute to the latest hot startup find themselves recruited by the Raytheons and General Dynamics type companies that recognize their skills are valuable.
[1] As an new college grad [NCG] I was not yet aware of the myriad ways in which employers would use non-disclosure agreements to thwart such conversations.
it's sad to me that most SV focus now is about how to sell more stuff to people whether that's through direct advertising or creating "social" platforms where people get to "influence" you into buying something or paying for something
Some congressmen had not heard of this technology and were working to fund a completely different (iirc, civilian) program intending to develop essentially the same capabilities. They had to go give a few TS briefings to the congressmen to dissuade them from writing the redundant funding into the next defense spending bill.
I make telescope mirrors.
This problem was well understood since the time of Herschel. We just have better solutions now.
The fact that this is a space scope is irrelevant to the fact that gravity will cause issues. For any telescope, you have to account for differences in the way the mirror is deformed in manufacturing vs in actual usage, and the ways the deformation will change in usage as the scope is leaning at different angles. That is always a thing.
What is particular to the Hubble is that the load in usage is zero (which is unusual), so you have to think about it that way in manufacture. But deformations in manufacture are always an issue you have to account for somehow.
Look at it this way: there is an ideal shape that the mirror needs to have, usually a revolution surface of some conic section (parabola, hyperbola, ellipse, circle). The performance of the mirror will track the difference between the ideal surface and the actual mirror. The error allowance depends on the wavelength λ of the observed radiation.
Telescopes where the error is greater than λ/4 just suck, and are unusable. Good performance begins around λ/8. A great mirror may do better than λ/20.
For visible light, λ/4 is 100 nm, or 0.1 microns. That's 10 thousand times less than 1 mm. On that scale, the mirror is made of jelly. If you put it on a rough surface, it will deform. If you put your thumb on it, hold it for a minute so it heats up from your skin, then pull away, there will be a "mountain" left behind on the mirror, under your thumb, until it cools off again.
In many cases, the support structures for large mirrors are complex mechanisms that ensure the force is uniformly distributed across a large number of points on the back of the mirror. Even amateur telescopes built using the Dobsonian template use passive self-balancing support with 3, 6, 9, 18, or even more points, depending on the size / thickness ratio.
Telescope mirrors might be a nice setting for teaching a lot of interwoven physics and material science stories.
A lot of engineering is like that. I wonder how we might start systematically collecting and organizing such stories, for eventual use in education?
The phenomena are pretty intricate. E.g. in the initial stages, grinding the mirror is a physical process: you use some very hard material to carve the glass into the desired shape.
But when it gets to polishing (smoothing the surface to optical perfection), it's far more complex. The granules of the agent are microscopic, and the process is in that grey area between physics and chemistry. You end up slicing off only a few layers of molecules at each pass.
It goes on and on like this. It's very addictive if you like Physics. :)
And given a firm grasp of size, and of atoms, it might perhaps be possible to support an integrated and broad modern material science foundation. Maybe... but I'm not being very successful at finding opportunities for exploratory discussion of that. :/
It seems like it could be great fun though.
[1] a couple of old test videos https://twitter.com/mncharity/status/1377384282633596935
I think a simple way to explain what your grandfather should feel proud of, is they documented the construction process so thoroughly that they were able to _precisely_ figure out what they did wrong, and fix it, on their first try!
https://en.wikipedia.org/wiki/Hubble_Space_Telescope#Origin_...
For some reason I had thought this (gravity stuff) was the problem. What was the actual problem?
I wonder how often retired NASA engineers are consulted. Imagine as an Engineer having to troubleshoot something which launched into space before you were born.
Of course there must be perfect documentation, SOP along with replicas on land.
I guess the worst thing you can fuck up in space fairing software is the boot loader. Mess that up and you can’t update the software.
Note: I have never designed software for space. I have no clue what I’m talking about.
Nobody told me we have to specify that! I thought that was the default and we only have to say when we are experts in something!
Now I have to delete all my posts.
Obviously working on such cool projects must be a major factor, but it's probably not the only one.
The project I worked one was migrating data from their in house ticket tracking system to Jira. I was importing tickets from 1985 into Jira which obviously didn't exist at that time.
Thanks for the insight!
I guess it IS very different to believe, for decades, in a mission that includes space telescopes than in the latest SaaS or productivity app or something more "mundane". Not that there's anything bad working on those kind of projects, but it sure has a different scope (no pun intended)
On a less sarcastic vein, some people find a job that they really like and enjoy. The pay may not be as much as somewhere else, but a satisfying job that is stable and provides for ones needs seems to be a concept lost in the tech (silicon valley) world. It's all about rocketships to the moon type of salary wants. If I found a gig like that sending manmade thing to another planet/moon that ultimately advanced human understanding, I'd definitely be willing to retire in that role. In today's world, there are plenty of other side hustles to help offset income needs. I'm a survey of 1 though.
As someone who hires people, lots of 18 month stints would certainly turn me off the candidate.
Though probably a "different world". It would be hard to retrain to do react development, for example.
That being said, I imagine it would be very hard to be a junior employee in such an environment. Fresh and green behind the ears, full of ideas and surrounded by people almost ready to retire and pretty set in their ways.
Who knows. Maybe these folks make an effort to stay current with progress in development tools and whatnot. But it is easy to imagine them being very stuck in their ways. Some for good reason but some because “that’s how we’ve always done it”.
I’d love to be told I was wrong and all their shop did a good job staying on top of industry wide progress.
My father was a senior admin in the vendor that made the mirror, so I had summer jobs working on Hubble-adjacent projects. One summer my cubicle was next to the cubicle of a new engineer who worked on it.
They ground the mirror in one facility and then trucked it to another one, many miles away, for silvering. This new engineer was tasked with drawing up the protocol for loading it on the truck (it was driven down in the early morning on a Sunday to reduce problems with traffic).
He finishes the document draft and calls down the senior engineer for a look-over. They are discussing the part where the cranes (kind-of like fork lifts) lift the mirror. There are three cranes, and three places built into the mirror where they hook on.
"How do you know the cranes will take the load?"
"Here are the manufacturer's specifications, saying that each will take more than half the total weight. There are three cranes, so there is sufficient capacity even if one crane fails."
"How do you know the crane will take the specified weight?"
"They were vendor certified last week; I was there."
"That's not enough. The night before, you and another engineer will personally go down there and personally load the specified weight on each crane. Then you will each sign a paper. The mirror will not move without that paper, containing both your personal names."
Made a big impression on me.
In space projects there's no space for human error.
Reminds me of that one SpaceX mission failure, with F9 exploding shortly after launch. IIRC, it was quickly determined that the cause was a strut from a third-party vendor that wasn't up to declared spec.
But nary a word from such commentators when a major commercial software product demonstrates yet another catastrophic security failure.
With government, you can only complain. So you do.
It took our IT over 4 years to migrate away from Siebel to Salesforce and it's going on 3 years since. I just learned the other day we still have a Siebel DB lingering around as a dirty little secret.
We move away from Lotus Notes over 10 years ago and we still have some Notes Apps used by our Legal Department.
With what's left of your budget, which is now very, very negative. Better to redefine abject failure as success to minimize the chances of it ending your career if you're involved in firm purchasing in any way. It's not like boards of directors have a clue. The big consulting firms will assist pulling the wool and priming the press so they can move onto the next mark. It's impossible to by cynical enough.
People love to shit on Oracle, IBM, etc when they bungle yet another big project that was supposed to fix something.
For instance, I’m happier if I pick my couch and then I’m uncomfortable than if the government picks my couch and I’m comfortable.
My dad was on an Air Force Base when the base commander delegated to his wife picking out all the furniture for the base housing. Naturally, every serviceman's wife hated it.
me: I think we can build something in-house here better than what the vendor will provide, I think the vendor's solution is likely to be a failure for us.
them: Yeah, but if do it in-house and it fails, it's our fault. If the vendor's solution fails, it's their fault -- plenty of very prestigious universities are using this vendor, nobody's going to blame us for choosing them. [Ie, "nobody got fired for picking IBM" basically].
At the same time, it shouldn't take twenty years to build a space telescope, especially since it's not like it's the first one ever. The first atomic bomb was built in 4 years.
Regarding the bomb, we were trying to end a global conflict, so the comparison couldn't be further off base.
Worst case scenario it doesn't blow up exactly right and you just build another one?
https://www.insidescience.org/manhattan-project-legacy/atmos...
Since it likely would have just blown up (fizzle) even if it didn’t fully detonate that is a pretty remote possibility.
Second worst would be it went off on a base somewhere and nuked a US base. Considering the location of these bases and the nature of the war at that point, it would have been a footnote causality wise, but embarrassing.
[0] Currently at least. Starship could I guess but it was planned way ahead of Starship even being a glimmer in Musk's eye. Do they have any grapple points on it as insurance? I would at this point, just put one of the posts they use on the ISS for Canada Arm to grapple.
The Nancy Grace Roman (formerly WFIRST) space telescope also has grappling points for robotic servicing so it is something that is being considered in designs for programs of record.
It’s simply how things are done around here these days.
In the SpaceX era of reusable rockets, those costs become 1-2 orders of magnitude smaller, and I expect a flurry of simpler space telescopes in the nearish future.
That's the theory. Does anyone know if such things are being worked on?
JWST costs upwards to 9 billion USD. An Ariane 5 launch maybe 200 million.
Just because the launch is cheaper doesn’t make the rest of the project less complicated and costly.
I think other actors can do similar things much cheaper and faster.
Think again. JWST was criticised for being too ambitious and rightly so. It uses technology that was (and in some areas still is) cutting edge.
It baffles me how people always seem to assume that some company can miraculously solve scientific and engineering challenges quicker and cheaper than the teams that are working on it.
JWST was designed with no serviceability in mind, that is, unlike HST it absolutely has to work. Every detail, from the folding mirror, to the sun shield, to the computer systems to the instrumentation. ZERO room for error and no "fail early, fail often"-option here.
Most of the delays have been caused by engineers and scientists wanting to make 100% sure they get it right, because there's no STS servicing for fixing imperfect mirrors or switching out hardware.
The James Webb Space Telescope (JWST or "Webb") is a joint NASA–ESA–CSA space telescope
The ignorance is really getting on my nerves. The mirror required a primary mirror segment assembly capable of surviving a rocket launch and still being able to be deployed in space at precision. This technology didn't exist back when JWST was approved and had to be developed from scratch, which was (successfully!) done by NASA Marshall Space Flight Center.
The prime contractor for the telescope (that includes building flight hardware) is Northrop Grumman, which, last time I checked, is not government owned.
ESA's main contribution is the launch vehicle, built and operated by Arianespace - also a private company. The other contribution from ESA is MIRI, a scientific instrument designed, tested, and built by a consortium also including some private companies like RUAG and EADS.
CSA contributes the Fine Guidance Sensor and the NIRISS instrument, both built by Honeywell, which, again is a private company. [0]
So while a ton of research and design work was done in government run labs, universities and NASA facilities, most of the actual construction was done by private companies.
So I really don't understand what you are trying to imply here. JWST was overambitious and pioneered way too many ground-breaking technologies at once while requiring absolute precision and "getting things right" due to its non-serviceability.
That's why all the delays and cost overruns happened and there was very little (of course not none) management and bureaucracy errors/overhead at fault here. NASA had simply bitten off more than they could chew with this one and there's absolutely no indication that any one company could've done better.
So you seem to have absolutely no clue what the heck you're even on about and what actually went into making of JWST and why it took so long.
[0] https://www.asc-csa.gc.ca/eng/satellites/jwst/canada-role.as...
Again with the ignorance: I just showed that it's not the government involvement that drove cost. It was because it turned out to be much harder than anticipated.
> Maybe there is more to it than it just being hard.
In this particular case, no there really isn't as annoying as that might be to the anarcho-capitalist/neo-liberal anti-government crowd.
The thing about NASA is that they're open and that includes their successes and failures alike. Delays are commonplace in private industry as well, but failure in particular more often than not results in bankruptcy and thus you never hear about it.
Just ask a venture capitalist how many high-risk tech investments actually turned a profit and within the anticipated timeframe. You only hear about the unicorns that made it or the ones that crashed and burned so brightly it could be seen from orbit. The majority dies like a drowning child - quietly and unnoticed.
I am sure someone can build a cheaper space telescope, but for whom and to what end?
I agree it was a milestone for astronomy, but it's been very long without any progress since. Why don't we at least have 4 more Hubbles in orbit?
Hubble - Visible / NIR, 1990 - Present
Compton - Gamma Ray / Xray, 1991 - 2000
Chandra - Xray, 1999 - Present
Spitzer - Infrared, 2003 - 2020
But again, even though it was "visible" it did not have many pretty pictures because the mission was looking at brightness variations in particular stars (planet transients).
> There's also JWST
Which is 15 years late and still on the ground.
The reason is pretty simple, there's no money to be made. Your potential customers are researchers scraping together grant money. There's no way to make enough to cover the CapEx and OpEx of a space telescope let alone make a profit.
There's no magic SpaceX fairy dust you can sprinkle on a project to change that calculus. The launch cost is a small portion of the total CapEx of a space based instrument.
Meant to launch in 2026.
"The PLATO payload is based on a multi-telescope approach, involving 26 cameras in total: a set of 24 "normal" cameras organised in 4 groups, and a set of 2 "fast" cameras for bright stars. The 24 "normal" cameras work at a readout cadence of 25 seconds and monitor stars fainter than apparent magnitude 8. The two "fast" cameras work at a cadence of 2.5 seconds to observe stars between magnitude 4 to 8. The cameras are refracting telescopes using six lenses; each camera has an 1,100 deg2 field and a 120 mm lens diameter. Each camera is equipped with its own CCD staring array, consisting of four CCDs of 4510 x 4510 pixels.
The 24 "normal cameras" will be arranged in four groups of six cameras with their lines of sight offset by a 9.2° angle from the +ZPLM axis. This particular configuration allows surveying an instantaneous field of view of about 2,250 deg2 per pointing. The space observatory will rotate around the mean line of sight once per year, delivering a continuous survey of the same region of the sky."
I posted a sibling comment, but both the proposed HabEx and LUVOIR space telescope designs would be visible-light.
The next Roman optical space telescope is slated for 2025.
The mirror in Hubble is 2.4 meters
Large ground based telescopes now have mirrors in multiple segments with motors keeping them at the right curvature.
The largest has 10.4 meter mirror. That is about 11 times larger area than Hubble.
https://en.wikipedia.org/wiki/List_of_largest_optical_reflec...
One of the original reasons for Hubble was to have a telescope above the atmosphere. The atmosphere distorts the light as it passes through making stars "twinkle."
Now we we use a laser beam to energize sodium atoms in the upper atmosphere. We see how that is distorted by the atmosphere so that with software we can cancel it out.
https://en.wikipedia.org/wiki/Laser_guide_star
Combined with lucky imaging where instead of taking a single long exposure we take thousands of images in the 100 millisecond range. We can toss out the images where the atmosphere was moving a lot and combine the other good images.
Kepler, Spitzer, Herschel, WISE and more. I agree that there ought to be more by now but its not like we did not see 'any progress'. Today we know hundreds of earth sized planets in the galaxy. If that's not progress, I feel the telescopes JamesWebb and NancyGraceRose will only disappoint you ;)
Hubble was launch in 1990, and have 5 servicing missions for repairs and upgrades, with the last one being in 2009.
An exact clone of Hubble is not nearly as useful as the first one, so it is reasonable to put your resources into a novel telescope. Unfourtuantly that telescope hit some scheduling challanges.
Not to mention all the other space telescopes https://en.m.wikipedia.org/wiki/List_of_space_telescopes
Which includes a gravitational telescope prototype.
NASA is well funded, not underfunded. It receives over three times the funding of ESA by comparison.
Why aren't the Europeans funding their scientific institutions better? Because the combination of soaring entitlement costs and stagnant growth robs them of the necessary tax revenue for that. Which is exactly what's happening in the US, and it's going to get a lot worse yet. The US has a bit less of an excuse, seeing as it could safely cut $200b off of its military. However, that $200b spread around to every squeaky wheel still won't go very far (it's equal to a mere ~2.3% of total government spending), you might be able to fairly boost NASA's budget by $3b per year if you slashed the military. Back in reality, that $200b in cuts should probably be entirely allocated to healthcare, which brings us right back to the central issue of priorities; and the Europeans know that quite well, which is why ESA is poorly funded.
Across all industries the average R&D budget is around 4%. When you look at the US R&D budget it's about 3% of the annual budget with 2% going directly to Military R&D and 0.5% going to defense and other military adjacent R&D. That's not entirely accurate thought because the Military budget for R&D also encompasses Training and Exercises. So only a fraction of that 2% is used for actual R&D.
That missing 1% is 3x Nasa's budget and 1.5 the DOD's.
(I came across this idea in a Tom DeMarco book called "Why Does Software Cost So Much?": basically people complain about the high costs of developing new software, but then for some reason they keep paying to develop more software. Even though the initial cost estimates may turn out to be fiction, it's still worth it because the benefits are so big.)
I worked in defense and had a coworker who thinks that NASA should be abolished and the US should cease all spending on space. Thinks it's all a waste of money.
There is also a sort of mini shuttle that has launched a number of times in the last decade called the X-37B which some have speculated might be used for servicing satellites.
It's definitely an interesting concept! The way you say the shuttle chased down satellites makes me laugh, as if the satellites were trying to escape and were zig zagging around! In reality, every mission to the ISS does the same thing as the shuttle rendezvousing with the Hubble.