Let's get actual figures.

According to [link|http://www.noao.edu/system/tsip/keck_cost.html|http://www.noao.edu/...ip/keck_cost.html], the cost of Keck is $25 million per year counting the telescope depreciating over 20 years, and operational costs. So we're talking $500 million. In the last 2 years they averaged 544 observing nights per year (they have 2 telescopes). For a night of observing that comes out to $47,400/night. If you get 10 hours per night, that is 4,740/hour.

According to [link|http://hubble.nasa.gov/faq.html|http://hubble.nasa.gov/faq.html], Hubble cost $1.5 billion to launch, and $230-250 million/year. It launched in 1990, and will continue until later this decade. So its total cost is about $6 billion or so. That is spread out over about 20 years, so that is $300 million/year, or $34,209/hour.

So anything that the Hubble can do which can be done by the Keck should be done by the Keck instead.

However if the price of space flight can be brought down significantly (and I think that it probably can), then at some point space-based observatories will replace adaptive optics. Of course that point is not now, nor is it in the near future.

And in the meantime there are things that can only be done from space. Two of those things are deep-sky surveys of background radiation, and scans of random locations for very, very distant objects. I mention this because those surveys are of critical importance to cosmology, which ties in to fundamental physics, which is (of course) Danny's interest.

So while adaptive optics can do some things, it is of no use for the things that affect Danny. Worse yet, it replaces some of what space-based observatories are good for, which lessens the chance of getting better space-based observatories up there. So this technology worsens the future of astronomy from his point of view. Which I suspect is a reason that he is so strongly opposed to the technology.

Cheers,
Ben