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On September 6th, the Association of Universities for Research in Astronomy (AURA) and the National Science Foundation (NSF) made the decision to temporarily vacate the Sunspot Solar Observatory at Sacramento Peak, New Mexico as a precautionary measure while addressing a security issue. The facility closed down in an orderly fashion and is now re-opening. The residents that vacated their homes will be returning to the site, and all employees will return to work this week.

AURA has been cooperating with an on-going law enforcement investigation of criminal activity that occurred at Sacramento Peak. During this time, we became concerned that a suspect in the investigation potentially posed a threat to the safety of local staff and residents. For this reason, AURA temporarily vacated the facility and ceased science activities at this location.

The decision to vacate was based on the logistical challenges associated with protecting personnel at such a remote location, and the need for expeditious response to the potential threat. AURA determined that moving the small number of on-site staff and residents off the mountain was the most prudent and effective action to ensure their safety.

In light of recent developments in the investigation, we have determined there is no risk to staff, and Sunspot Solar Observatory is transitioning back to regular operations as of September 17th.

Not that that will stop the conspiracy nuts.

(I'm scanning down to see if anyone else has mentioned it.)

Note that I had a wrong link to AURA's response (still a PDF though)

Yes, NRAO and NOAO are very different and in charge of different things.

But contrast NRAO's initial response (here) to that of NOAO (here) or even AURA (here, sorry its a PDF) to see the different approaches that are possible.

NRAO essentially criticize the portfolio review process and reject the results outright without consideration and essentially hopes that the NSF figures out a better way: "AUI and NRAO encourage the NSF to work with its other federal agency counterparts to consider a more balanced approach with additional funding scenarios for the entire U.S. federal astronomy portfolio." Compare that to NOAO's response which creates an online discussion point, lays out specific details about each relevant point, encourages all astronomers to talk to their congress people, as well as making observations about the situation between NRAO and ALMA being similar to NOAO and LSST.

This isn't a time to complain about losing one or two specific facilities, this is a time for talking about the entire picture of how bad this would really be if divestment goes through and facilities are either closed or put into private (closed) consortiums. NRAO's response honestly comes across as sour grapes defending their own stuff with little concern of the greater picture.

While I understand how you might come to this conclusion, it's actually completely wrong. You demonstrate enough knowledge to intelligently question the case for space (which is relatively rare actually, but probably common here on /.), but not enough to answer it. I can't let these ideas go unchallenged because the only way new missions will be funded is if lay people continue to support them.

All of the points you made are easily refuted (see below), but the main point is that we simply must go to space to do most of the _new_ exciting science, primarily in new wavelength regimes and at high resolution.

1) "thanks to interferometry one can get the resolution (equal or better) with earth based telescopes for a fraction of the price of space-telescopes like hubble"

- ALMA is also a $1B telescope. Just because it's on the Earth doesn't make it cheap! ALMA is a good example of a great ground-based telescope, in that it can do cutting edge science more cheaply than in space. Trust me, from the NASA perspective we're very aware that you have to PROVE that your idea can't be done from the ground before you get anywhere in designing a space mission. The problem with ALMA and all interferometers is that you can only get high resolution imaging over a *tiny* area, usually just one galaxy at a time. It's great for learning about that galaxy, but useless of wide-field science like cosmic shear measurements (eg. http://www.physorg.com/news87400827.html).

2) "And thanks to adaptive optics there is hardly any atmospheric blurring which smears out the pictures anymore"

- Again, this is only true over a tiny area, typically less than 40", with a strong gradient of image correction leading to data which is very hard to work with and photometer. Useful to get the shape of 1 galaxy at a time, but that's it. And even the maximum AO correction, on axis, is inferior to what's possible from space. The sky background is also vastly lower from space, allowing us to peer much deeper into the Universe for the same exposure time. Here's some info on the limitations of AO http://www.aura-astronomy.org/nv/hst_vs_ao_2.pdf.

3) "And, since the mirrors can be bigger then those send into space, the light-gathering power is way superior for earth-based telescopes."

- Potentially true. That's why 3 groups are proposing to build a massive 30-m telescope here on Earth do adaptive optics imaging and spectroscopy. It will assume with the upcoming James Webb Space Telescope (JWST) the role the Keck 10-m telescopes currently play with the Hubble Space Telescope (HST). It will be a big light bucket allowing us to spectroscopically observe objects detected by JWST. Oh, and it will also cost $1B or more.

4) "The only advantages left are for specific wavelengths (like near-infrared), because the atmosphere absorbs most of that, but even that is more and more debatable, now that new instruments and detectors are becomming so sensitive that they can detect and use it on Earth too"

- The atmosphere actually absorbs most wavelengths, though we've been so optically-oriented for so long it might not seem like it. On the blue side, we need to go to space to study objects in gamma rays, X-rays, the far and near UV. On the red side, from about 3um to 300um we must also go to space. At longer wavelengths (eg. submm) we can work from the ground, but it's very, very hard until we get to the radio.

The atmosphere is opaque on the blue side, so no new instrumentation will not help. On the red side the are atmospheric windows we can peer through, but the issue is that everything (the telescope, the dome, the earth!) radiates thermally at precisely the wavelengths we're trying to observe. And they're thousands of times brighter, so even if we cool the IR detectors it still doesn't work very well. As an example, before the Spitze

According to an article in the Denver Post:
"Sending a heavy satellite into orbit costs tens of millions of dollars, or approximately $10,000 a pound."
So, even if these 10cm cubes keep it to one half pound, they're still looking at a $5,000 bill to get it into space. But apparantly, the Bush administration is spending much to find new methods or vehicles to reduce this cost (hopefully soon).

There are a host of other issues with ground-based adaptive optics that limit their use (namely, you can only do it in the optical vicinity of reference stars). Because of the infrared performance, perhaps your argument works against building the JWST.

A nice review of the issues involved can be found here.