Did NASA Ground SOFIA?
Computing a Winner, Fusion a Loser in U.S. Science Budget, Science Insider
“A White House summary of NASA’s budget notes that the savings achieved by reducing funding for SOFIA will enable “continued support for higher priority programs, including lower cost, competitive science missions, and extended operations for the Cassini Saturn mission.” A more detailed presentation of the space agency’s budget proposal, unveiled this afternoon by NASA, says the agency is in talks with its German partner to determine the best path forward for SOFIA.”
Hertz says MOU with DLR for SOFIA calls for 20 years but #NASA is cutting it and yet NASA won't admit that 20 yrs of ops won't happen.
— NASA Watch (@NASAWatch) March 4, 2014
Bizzarre that Hertz says SOFIA is being cut due to lack of funds but he cannot say how much DLR needs to provide to keep it flying. #NASA
— NASA Watch (@NASAWatch) March 4, 2014
SOFIA’s fate is not unlike that of SLS and Orion. Numerous delays lead to a project life-cycle that ran from 1996 to 2010, fourteen years. Total cost rose as a result, too. But it is one of a kind, state of the art. It just took too long. Present and upcoming space-based infrared scopes and the latest sensors have marginalized its performance. And when one considers the cost of maintaining flight readiness and flying, it is hard to justify continued operations.
It is a _beautiful_ engineering feat and the designers should be proud of their accomplishments. This is a Mount Wilson (Hooker reflector) sized mirror (2.5 m, 98 inches) for infrared that flies at over 40,000 feet, peering out the side of a Boeing 747 with precision guidance. Truly amazing. One can arguably say the same for SLS and Orion (can we?), i.e. trying to justify their completion in light of protracted development, cost to complete, to maintain flight readiness and lack of reusability and now commercial alternatives on the scene.
One of the contrasting features of SOFIA that is testimony to its lengthy development is that the on board instrument control systems, the computers are based on Sun Solaris and software from the late-90s. There is upgrading but the question is now whether the cost can be shared with more partners to continue flying. There is demand for SOFIA because the demand for telescope/instrument time is so high across all of the field of astronomy.
There’s nothing wrong with looking for new partners. But that 747 probably costs over $20,000 per hour to fly. Why not dismount that beautiful telescope and fly it up to the ISS in the trunk of the Dragon capsule? There was a plan to mount scopes of about this size on the station; as long as the mirror can be covered during Soyuz approaches it’s my understanding that contamination is not the problem it was once assumed. Oh, and ditch the Solaris hardware for a PC and Linux.
That’s not such an outlandish idea. There are obstacles to putting anything on ISS though. That would take time. Bureaucracy. Also changing the electrical, data interface and mounting system would be another big issue. The power it would draw might be an issue for ISS limits. Alternatively, why not make it a free flyer in orbit? That is kind of like taking the stubby Hubble-class spy telescopes that DOD gave NASA and making them fit for flight. Probably more work with the SOFIA scope. But its true that a Falcon 9 with 5 meter fairing would easily hold a 2.5 meter telescope. Making it a orbiting telescope would likely be ~$300M not unless you could get some off-the-shelf spacecraft bus, for example, from Ball Aerospace (kuiper bus) or LockMart (Spitzer). You might be able to do it for $200M that way. And as you say, a Falcon 9 launch would tack on another $55M, rather than the ~$100M of a Delta II (all spoken for anyways), $150M of a Delta IV or $200M of a Atlas V. If I was designing such a space telescope from SOFIA’s scope, I would make the cryo tank modular so that a small robotic vehicle could service it at some later date – recharge the liquid helium; also permit it to function like Spitzer and NeoWise in a “warm” mode. Nevertheless, taking a terrestial-based scope and converting it into a space-based one holds probably some real technical problems.
The telescope assembly weighs 35,000 lbs and wasn’t designed for operations in space. I’d imagine that for the fraction of the cost of modifying it, one could design and build a similar optical system for the ISS. But it would be highly inefficient operating in LEO (as is HST with ~ 35% observational efficiency) because of the need to avoid pointing at or near the Earth, Moon and Sun. Not to mention the contamination environment. So there is little interest in any sort of astrophysical observational use of the ISS. Observational efficiency is a major reason why NASA stopped building LEO observatories, starting with Spitzer.
I wasn’t aware it weighs that much and I’d agree that by starting from scratch one could likely make the equivalent more cheaply. But its entertaining to imagine what-if. The cost estimates I mention are probably too low. The stubby Hubbles from DOD pose, as mentioned, a similar problem. Reconfiguring them to do something scientifically useful runs into cost. The NASA budget doesn’t have the surplus for them right now. One thought for them is to put one into Mars orbit, as is, for high resolution imaging.
Most of that weight is for the complex mount required to support and guide the telescope under 1G in a moving aircraft. According to http://arxiv.org/ftp/astro-… the telescope itself has a mass of 850Kg which is well within the cargo that can be accommodated on an already scheduled (and budgeted) SpaceX or Orbital logistics flight. There would be a cost for a zero-G mounting system, but because the motion environment of the ISS is much more benign and forces are much smaller it would be only a fraction of the mass.
Because the ISS (and the Shuttle, before) is a terribly dirty environment. At one time there was a lot of talk of flying space telescopes on these things, but early studies with small telescopes showed there was so much micro-debris flying around that they were almost useless (specifically, I know personally of tests done in the IR, which is where SOFIA’s bread and butter exists). You also have the aforementioned pointing constraint issues – almost all space telescopes are headed to L2 now.
There will be more posturing and pontificating in the House and Senate for their pork barrel projects over a project that is peanuts in comparison. If the SOFIA project is canned, turn the thing over to DLR instead of putting it in mothballs.
That would be an excellent idea if one of the IPs is able to pay the operational costs, which are quite high. One difficulty I see is that ground-based astronomy, particularly in the IR, has advanced a lot in the decades since Sophia was developed. I would be surprised if it is still cost effective in comparison with spending the same money on ground-based observations with a larger scope. That’s why I see ISS-based ops as being the answer. Once it gets up there it’s not burning jet fuel.
Besides the science it’s also a unique airplane, and not just because of the modification for the telescope. The 747SP (Special Performance) was rare even when new, only 45 were built and just over a dozen are still flying. The 747SP was a shorter variant of the 747-100 (nearly 50 feet shorter) which gave it longer range and higher speed than a regular 747 of that era. If you look at the photo you may notice the seemingly oversize tail, required due to the decreased leverage caused by the shorter fuselage length.
I have always assumed that the 747SP was selected for SOFIA specifically because of its performance capabilities, although I have never been able to confirm that. Even though a typical SOFIA flight doesn’t seem to go any farther or higher than a regular older model 747 is capable of, I’m sure there is quite a bit of drag when the door is open and the extra performance of the 747SP helps to compensate for that.
The Boeing 747-SP was the only aircraft that a US contractor could modify that was capable of meeting the Level 1 requirements of carrying the 35,000 lb payload above the tropopause for more than 6 hrs at a time.
This is very sad news if this is true, especial since I understand that SOFIA was just declared “operational” by SMD. Ops cost sharing with other international partners should be easy to set up because much of it’s costs relate to ops of a commercial aircraft (jet fuel, engine maintenance, etc), so this move makes sense in this budget environment.
I think any speculation on NASA funding in the current WH budget is probably a wasted exercise. The House has a budget deal in place through next year and Speaker Boehner has already stated that this WH budget is DOA. Also, there will be no CR this year, so NASA budget is pretty much as is for now. (I base this on what I’m reading in Washington Post and a couple of other news sites. I could be wrong, tho.)
The other key issue is that SOFIA took so long, it’s time has passed. When it was first pushed as a successor to KAO it made sense (more than 20 years ago!). Today, not so much. It’s sensitivity is very poor by modern standards, particularly in the current space telescope (Spitzer, JWST, etc) era. It has some niche science topics where it really shines (like ultra high spectral resolution spectroscopy of very bright objects, like in the solar system). But thanks to the delays, it has now cost more than a space mission would have, and its annual operating budget is as high as a space mission operating budget, in large part due to ballooning fuel costs. In terms of science per dollar, it’s really hard to justify. NASA actually tried cutting it free a number of years ago, but there’s international treaty-level politics due to the partnership with DLR.
The German partners are not taking this well.