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We know how old the universe is. That's not meager, that's one of the most profound discoveries of history.

We would have learned that anyway with Earth based observation.

Then you complain about NASA costing too much and at the same time want more Mars rovers.

Then you didn't get it. Those Mars rovers were paid for with existing NASA funding. More exploration, sooner. Don't you want that? My point here is that even ignoring whether NASA is actually doing anything useful or whether SpaceX and similar businesses can lower cost of access to space, we can still greatly improve what NASA does and the outcomes it gets through some simple changes such as doing things more than once.

As for your patronizing "read up..." - I WORK on this. For a private company, I'm not going to say which. And I dream of NASA contracts because then I'll be working on something that will be a real contribution.

Even worse. Someone who should know better, but chooses to sacrifice our future for a piece of the sugar. I will say this. Despite your claim to "work on this", you still sound profoundly ignorant, else you wouldn't continue to advocate an approach which is a proven failure over 60 years.

You've got private enterprise exploring even though they don't, you complain that NASA doesn't build enough telescopes and probes, even though no-one else would ever fund this real exploration of space.

Don't get me wrong. I find this to be a solid indication that what NASA does, isn't worth doing at the price. But ask yourself these questions: why should private enterprise get involved when NASA burns so much more? Why should suppliers who make such things get involved when NASA contracts are so much more plush and risk-free? If I were to come up with a space exploration system and actually launch it at someone's expense, what's to keep NASA from one-upping it with a much more expensive program than I can ever do?

That last question is quite relevant because there's been a few times particularly during the 90s when NASA killed private efforts (for example, the entire market for very small payload launches) by introducing its own publicly funded competitor. NASA can't be bothered to run a serious space exploration program, but it can be bothered to knock down the competition in order to avoid embarrassment.

Show me SpaceX's moon-mining project? You can't - doesn't exist. Show me Bigelow's Mars rovers? Or anyone's Europa probe? Or a private Hubble? Or McDonald's Planck replacement? Show me something that private enterprise is doing to explore space, not just exploit what NASA has already done for commercial gain. Of course private enterprise has a role to play here, but it would be nothing without the pioneering work of NASA. Private enterprise sits on the shoulders of giants to pick the cheap fruit.

The Keck telescopes are one such counterexample. The first attempts at a solar sail were privately funded (aside from cheap launches through the Russians). And then there's SETI which is privately funded these days.

As far as calling NASA "giants", I'm not saying that their work is completely without value, but that it isn't worth the cost that has been paid for it. Nor have they made even fairly mundane efforts to reduce their costs. Sure, it's nice that NASA's work actually gets used for something, but think about that. The only real value that we're getting out of NASA is some prep research for businesses like SpaceX or Bigelow. And we might know the age of the universe to a slightly greater accuracy than otherwise.

Just what one needs to image the black hole at the center of the Milky Way. If they can get the timing right, between this set of 4 telescopes operating as one, the Keck telescopes in Hawaii, and the Spitzer IR Space Telescope, we could have a virtual telescope in the IR band that is easily 30,000 km wide.
http://www.keckobservatory.org/
http://www.spitzer.caltech.edu/

Btw: This idea increased spatial resolution using very long baseline interferometry is why it would be worth a few billion dollars to send multi-spectral moderate aperture telescopes to the L4 & L5 points, IMHO.
http://en.wikipedia.org/wiki/Lagrangian_point

Just to flesh this out and offer a few corrections, as someone who works around the AO LGS at Gemini (and Keck):

Tomduck is correct that an adaptive optics (AO) system uses deformable optics to bring a guide star into sharp focus, and the rest of the scene with it. He fails to mention that this process is in no way inherently dependent upon the use of a laser. Indeed, when a bright natural star is close enough to the target to be used, it is in many ways preferable to using the laser. (For one, the brightness of natural stars tends to be pretty constant, and not subject to the usual game of "so, how many watts shy of nominal power are we tonight?" :) So Gemini's AO system, Altair (read all about it here) is quite often used with natural guide stars (NGS).

A NGS can, incidentally, also be used for guiding - keeping the telescope pointed correctly - as its name implies. This isn't the case for a laser guide star (LGS), which in fact has absolutely no use for pointing, since the laser is fastened to, and aligned with, the telescope. It's a horrible misnomer. :( LGS come into play because the field of view of large (8-10m) telescopes is narrow enough that NGS are frequently not visible at the same time as science targets.

There are three large telescopes on Mauna Kea with LGS capabilities - Keck II has an older-technology sodium dye laser (pumped/amped by about six YAGs), Gemini has a solid-state (crystal) laser, and I'm not certain what Subaru has as I haven't worked with them yet. The W.M. Keck Observatory has funding to put a laser on Keck I also, but I'm unsure when it'll be operational. All of the lasers propagate at around 589nm for sodium fluorescence (this is coincidentally about the same frequency put out by the low-pressure sodium streetlights used in the towns on the island, so astronomers can pretty much ignore this frequency).

Each beam is about 8-12W with an objective lens diameter of typically 30-50cm, spreading a little as it goes up. Not enough power to punch holes in stuff, but enough that the FAA requires aircraft spotters to be positioned outside each observatory to make sure they don't blind the pilots of flights between the west coast and Australia/New Zealand. I've done this work sporadically since 2005 at Keck and 2006 at Gemini, so I have tons of pictures and time-lapse video... here's one of the Gemini beam with me ruining the picture by sitting in front of it.

Along with the FAA, AFSC (that's Air Force Space Command, not the American Friends Service Committee) is rather particular about us not shining the bright lights into the sensitive sensors of keyholes and such things. We look up, they look down, etc.

By the way, if there are any Farkers on the Big Island of Hawaii who think this kind of work sounds like fun, it looks like Keck has openings. It's temp-agency work, and probably the coldest, highest-altitude temp-agency work you'll ever get...

Resolution increases linearly with aperture. The effective aperture for the LBT would then be the separation of the two telescopes plus twice the aperture (8.4 m) of either. You only get that increased resolution directly along only one axis--the one through both telescopes. So you take multiple images and do some math, and in many cases you should be able to arrive at the max resolution--which is equivalent to a single instrument of 22.8 m aperture.

See my post above, open the 'why build' link in another tab, and scroll down to the simulated infrared images of Io. Now see
http://www.keckobservatory.org/article.php?id=54
which is another image of Io in infrared, from Keck, which is a very large, highly-capable system, at one of the best sites in the world. If the LBT reality is as good as the simulations--wow.

BTW, the light-gathering power varies as the square of aperture. So this pair of 8.4 m mirrors gives you the equivalent of a single 11.8 m instrument. So as a light-bucket, it's quite as much of a win as it is in resolution. But 11.8 m is still huge. The Keck telescopes are 10 m., for instance, and astronomers were stoked about them coming on line.

This stuff knocks me out. I remember seeing images of the Jovian moons in which you barely tell Io was a bit off-white.

While I understand the frustration at the idiot comments that have been posted so far, I think you are way off base in regards to the scientific research and education that goes on in the US. If you were too lazy to read the article before responding, the summary even states that the US has supplied funding for this project.

While it is amazing that Mexico has built a new LMT, I feel obligated to remind you of the multiple telescopes the US operates such as Gemini, KECK, NASA IRTF, CSO, SMA, NRAO. These are but a few off the top of my head.

Keck (both I and II) got damaged during last week's earthquake ( article ) and they're still working to get Keck II back to operational status. You never know when you will lose a valuable asset through a natural disaster... it would be ironic if the Keck system got wiped out shortly after the Hubble telescope was allowed to deteriorate beyond a reasonable threshold for maintenance or upgrading.

the Charismatic Megafauna problem would affect NASA?

Since Hubble's replacement is already under construction, and since ground based scopes like Keck exceed Hubble's capabilities, what is the benefit of dropping hundreds of millions of dollars repairing it?

I occasionally also stare at the sky over at this other place around the corner from the first one, but in a much less significant capacity. :(

We likes the big shiny toys, my preciousss...

Adaptive optics coupled with some monster telescopes can give imagery better than Hubble.

But of course saying so won't get anyone some Bush Derangement Syndrome mod points.