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The James Webb Space Telescope (JWST), an infrared space observatory with an $8.8 billion budget, will be transported to South America to launch atop an Ariane 5 rocket, presumably in Spring 2019. The JWST was not intended to be serviceable at the Earth-Sun L2 point. Will there still be a "Golden Age of astronomy" even if the JWST fails?
[Due] to its steadily escalating cost and continually delayed send-off (which recently slipped from 2018 to 2019), this telescopic time machine is now under increasingly intense congressional scrutiny. To help satisfy any doubts about JWST's status, the project is headed for an independent review as soon as January 2018, advised NASA's science chief Thomas Zurbuchen during an early December congressional hearing. Pressed by legislators about whether JWST will actually launch as presently planned in spring of 2019, he said, "at this moment in time, with the information that I have, I believe it's achievable."
[...] Simply launching JWST is fraught with peril, not to mention unfurling its delicate sunshield and vast, segmented mirror in deep space. Just waving goodbye to JWST atop its booster will be a nail-biter. "The truth is, every single rocket launch off of planet Earth is risky. The good news is that the Ariane 5 has a spectacular record," says former astronaut John Grunsfeld, a repeat "Hubble hugger" who made three space-shuttle visits to low-Earth orbit to renovate that iconic facility. Now scientist emeritus at NASA's Goddard Space Flight Center in Maryland, he sees an on-duty JWST as cranking out science "beyond all of our expectations."
"Assuming we make it to the injection trajectory to Earth-Sun L2, of course the next most risky thing is deploying the telescope. And unlike Hubble we can't go out and fix it. Not even a robot can go out and fix it. So we're taking a great risk, but for great reward," Grunsfeld says.
There are, however, modest efforts being made to make JWST "serviceable" like Hubble, according to Scott Willoughby, JWST's program manager at Northrop Grumman Aerospace Systems in Redondo Beach, California. The aerospace firm is NASA's prime contractor to develop and integrate JWST, and has been tasked with provisioning for a "launch vehicle interface ring" on the telescope that could be "grasped by something," whether astronaut or remotely operated robot, Willoughby says. If a spacecraft were sent out to L2 to dock with JWST, it could then attempt repairs—or, if the observatory is well-functioning, simply top off its fuel tank to extend its life. But presently no money is budgeted for such heroics. In the event that JWST suffers what those in spaceflight understatedly call a "bad day," whether due to rocket mishap or deployment glitch or something unforeseen, Grunsfeld says there's presently an ensemble of in-space observatories, including Hubble, and an ever-expanding collection of powerful ground-based telescopes that would offset such misfortune.
Previously: Space science: The telescope that ate astronomy
Telescope That 'Ate Astronomy' Is on Track to Surpass Hubble
Launch of James Webb Space Telescope Delayed to Spring 2019
Launch of James Webb Space Telescope Could be Further Delayed
(Score: 2) by VLM on Monday January 01 2018, @03:55PM (5 children)
I'm too lazy to look up specific examples but aerospace one-offs are famous for huge fixed R+D costs, so if the first one blew up on the pad, one aspect of having blown "most of" $8.8 Billion on R+D means they could probably build a second one for like half a bill.
An interesting conspiracy theory I read awhile ago was the JWST is a NSA front and they in fact are going to use the R+D to launch a "many" near clones of the platform but with NSA style sensors. Obviously the astronomical instruments on the JWST built by universities would be useless for the NSA, I mean the whole infrastructural aspect of the satellite but with visible optical spy gear instead of deep sky astronomical IR or whatever. The gyros and thrusters and antennas don't care if the camera is looking at deep space nebula or Afghanistan. Thats also why they like a nice heavy tank of coolant, not just to keep the JWST running but the NSA models will ship with that mass and volume packed full of sigint gear or adaptive optics foolishness or something.
(Score: 2) by takyon on Monday January 01 2018, @04:17PM
JWST doesn't use a "tank of coolant". It uses a passive cooler. The telescope is specifically designed to be facing away from the Sun constantly using a sun shield, and is also not being pointed at the Earth or Moon. So not so applicable to Earth-facing spy sats. The telescope's useful lifetime is limited by the propellant it needs to keep steady at the Sun-Earth L2 point, not any coolant (I found this out the hard way after repeating incorrect info a couple of times).
Spy agencies already send up "space telescopes". WFIRST is based on a donated National Reconnaissance Office telescope [wikipedia.org]. I don't see what JWST's development has to do with anything. Could the unfolding mirror design help spy sats? Sure, whatever. That design is also being used for other proposals [wikipedia.org] going forward.
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(Score: 2) by bzipitidoo on Monday January 01 2018, @06:11PM (1 child)
Among reasons for the huge costs of the Superconducting Super Collider was Congress changing their minds, forcing a great deal of additional expense to idle people and mothball things repeatedly. Do you dismiss the science staff whenever funding is cut or even looks likely to be cut, knowing you'll have a hard time replacing them, or do you keep them all on the payroll in hopes that Congress will find the will to stay the course and pony up the money that was promised, soon? It stood accused of bad and wasteful management, but at least some of that was the fault of Congress.
James Webb has the same problem. Its high costs put it on Congress' radar, and that's never good. Congressional fickleness makes it very hard to do expensive, ambitious science.
(Score: 3, Informative) by takyon on Monday January 01 2018, @06:41PM
I don't think Congress can be blamed for JWST cost overruns.
https://en.wikipedia.org/wiki/James_Webb_Space_Telescope#Cost_and_schedule_issues [wikipedia.org]
Congress's action didn't mothball JWST or cause it to waste more billions. There were many delays that had nothing to do with Congress, the capabilities expanded from the original proposal (but with the mirror diameter cut down from 8 meters) and "significant changes in the integration and test plans" caused delays.
http://www.nature.com/news/2010/101027/full/4671028a.html [nature.com]
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(Score: 1) by khallow on Tuesday January 02 2018, @12:55AM (1 child)
One aspect though is that any spy satellite actually has more need for a heavy tank of coolant and/or propellant than the JWST. The latter, being well past the far side of the Moon, would only have to deal with heating from the Sun. A spy satellite would have to deal with heating from both the Sun and the Earth (Earth would be a much larger source of heat being far closer for the spy satellite). You couldn't get away with the same modest passive cooling system, because you couldn't merely point your radiators away from the Sun. You also would need to have those radiators pointed away from Earth. So either scrap the cooling system and go with the heavy tank of coolant or expend more propellant in station-keeping.
(Score: 2) by VLM on Thursday January 04 2018, @02:46PM
I'm familiar with the HST / Keyhole situation and yeah this is just the next generation.
The JWST is an Infrared long wavelength program needing cooling, which probably isn't useful for spies (although not being one I donno, maybe an orbiting IR cam would be awesome for monitoring "stealth orbiting satellites" or something). So slap in visible optics, and use the volume/mass/watts the cooling system used for crypto gear or sigint gear or whatever weirdness spies like.
As example 1 of several which I can't remember in detail, mirrors stop working when they're more than a tenth wavelength out of whack (handwaving approximation). The OTE actuators are published to be spec'd to 5 nm resolution. So the infrastructure of this "IR" telescope would work as an absolute kick ass spy scope at 500 nm which is blue green light. If they were really building infrastructure for a far IR scope they could save some coin by spec'ing actuators only good to, eh, 300 or so nm. That would be "good enough" for the claimed purpose of 3um astronomy, or OK fine we'll splurge and install 50 nm actuators. But no they blow budget on something just good enough for a visible range spy sat... huh. What a coincidence.
There was another coincidence about the commo power budget being higher than scientifically necessary but sure would be convenient for rapid tactical spy stuff. This is handwavy and I can't find the docs online to prove it so I'm suspicious about this one. But I would not be shocked to discover the thing has the power budget in commo to downlink real time visual wavelength resolution scans, which seems kinda silly for something ostensibly a scientific low res IR camera.
Yeah engineers always like to ship something better than "just barely works" but the coincidence is all the feather bedding is suspiciously just what a visual spy sat would need, not a random bell curve that you usually get.
Aside from engineering coincidences, obviously the power bus, commo, gyros, all that stuff doesn't know or care if its commanded from mission control in FL or being controlled from Ft Meade, it'll work perfectly for either.