In which NASA gets presented with two Hubble class wide field space telescopes...
Oh my. So some of the mysterious maneuverings at NASA's Astrophysics division can now be better understood.
The National Reconnaissance Office was sitting on a couple of spare space telescopes they are willing to transfer to NASA.
These are presumably late block Keyhole reconnaissance satellite spares, maybe even the two extras orders a few years ago at the end of the program.
So, state of the art as of 10-20 years ago.
We are looking at two partial telescopes, with a Hubble size primary mirror, 2.4m, but with a wide field of view and diffraction limited in the near infrared (at 1.5 microns).
These are very nice telescopes.
They come with an adjustable focus secondary and a tertiary mirror on a long bus with room for two wide field instruments, and maybe two smaller narrow field instruments.
The resolution is comparable to Hubble, slightly better in the near infrared. But the field of view is about 100 times larger, which makes a big difference for a lot of science.
A group of lucky select scientists were give a peek at the toys and got to do some spec'ing of what could be done.
The spacecraft need power, electronics, comms, and steering.
As well as instruments and launch.
And, of course, MODA - Mission Operations and Data Analysis.
Board on Physics and Astronomy presentation at the NRC
Paul Hertz - New Developments in Astronomy and Astrophysics
- NASA's Paul Hertz summary of what we have
Alan Dressler - Implications of New Developments in Astronomy and Astrophysics
- excellent exposition from Carnegie's Alan Dressler on what could be done with these.
Lots of model science presentation.
[caption id="attachment_2543" align="alignnone" width="300" caption="NRO-1 simulated performance"]
Slide from Dressler's BAP presentation comparing HST and NRO-1 performance[/caption]
The primary thinking is a fast and cheap WFIRST,
stick a 16 chip Hawaii 4RG camera on the back of one and get it up to GEO (probably as best orbit tradeoff).
Squeeze in some secondary science to keep everyone else happy and then try to fit the second unit for some complementary science.
We are probably talking roughly $1 billion to outfit and launch each telescope - just the instruments are O($100M) each and you'd want 2-4 instruments per spacecraft.
Power, electronics, comms and steering cost some also.
MODA would be $30-50M per year at a guess.
There is no money in the budget to do this, unless something gives, BUT, it is still cheaper and faster than doing it from scratch.
Gonna have some fun with the new toys, hopefully.
Really makes you wonder what the new generation recon satellites that the NRO has can do though...
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There is a vibrant discussion of this on the Astronomers group on fb
Wow. These are probably the best news in astronomy since few years of bad ones.
So, uh, would it be cheaper and faster to design the instruments and spacecraft for one of these guys, and launch it, than it would to finish JWST?
In other words, could one see these as competitors for JWST, in a world with constantly shrinking astronomy budgets?
Not to look gift horses in the mouth, but unless NRO is willing to provide a WHOLE LOT of information about these telescopes, NASA is going to have reverse engineer them to understand exactly what they've got, and have confidence in it. That could get quite expensive.
Also, what we're looking at here is not a large fraction of the total cost of a mission. Aside from the optics, virtually all the other hardware would need to be replaced, as it is older technology, and likely not consistent with NASA-standards.
In no way would these be considered to be competitors for JWST. Won't happen. In fact, NASA Science Mission Directorate won't commit serious funds to them until JWST is launched. Exactly the way they were going to approach WFIRST.
Would it be cheaper to launch one of these than to finish JWST? Almost certainly not, plus these are less than half the diameter, and not designed to passively cool to be operated all the way into the mid-IR like JWST. So they're less capable (in terms of depth anyway). These are wider field telescopes while JWST, like HST, is a narrow-ish field telescope that can go very deep. Besides, JWST has a full instrument complement that is nearly completed. If you started designing a cutting-edge instrument for one of these tomorrow it might not be finished and tested by JWST's launch date.
It has already been noted that what they could make public about the telescopes might have been ITAR limited even if not classified. That is not a stumbling block per se - all sorts of things, including pieces of JWST, are ITAR-restricted. These things were built by the same set of aerospace contractors. They may be pigs in a poke, but I don't think NASA is going to have to reverse engineer them. If NRO cared they wouldn't give the telescopes to an outfit that *could* reverse engineer them.
I suspect that what matters here is not that the telescope and (partial) spacecraft are the bulk of the cost of the mission, but they are the piece that takes the longest time to develop. That could save a lot of lead time and salary money. For ex right now the JWST instruments are nearly completed (MIRI has shipped) but they have to keep people from the instrument teams around for years while the whole structure is completed, because if you've lost the expertise by launch time you could get into trouble.
My point was not "could a space telescope built around one of these platforms do what JWST could do?" or even "Could a space telescope built around one of these platforms do world-class science?" I was trying to ask the question, "If the astro budget continues to decline, and JWST continues to grab most of that budget, and the JWST deadline continues to slip ... would some members of the community use these telescopes as _an excuse_ to build something quick and cheap which would replace JWST?"
In other words, could people who are pissed at JWST attempt to use these telescopes to sink JWST (and, most likely, end up with nothing)?
As to whether these telescopes could do what JWST could do, the answer is abundantly NO. They aren't large enough, so they don't offer the spatial resolution, and most importantly, they were never designed to operate at cryogenic temperatures, so there is absolutely no assurance of what would happen to the optics, or the structure even, if the lights are turned out.
Could they do world class science? Sure, why not, but what would be doing the world class science is the stuff that is added to these telescopes. Validating these telescopes to perform properly, and adding all that stuff will cost a lot. World class? That's a funny phrase. The NRC Decadal Committee devoted more than a year to decide on priorities for what, among gobs of "world class" science, was best done. "World class" ain't good enough.