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Dr. Spork is on to something here. We still know so very little about our universe and by far the best way forward is to develop very large aperture telescopes. Humans are headed toward building truly massive optical telescopes (100m scale this century, maybe 1km scale in the 2100s or 2200s). Right now we need to succeed in getting the James Webb 6.5m telescope in space and the 30m earth instruments operational. There are several ideas about how to build 100m scale optical telescopes. (See the OWL proposal, http://www.gemini.edu/science/...) One path is to use many independent small telescopes and combine the light as is done with interferometers. Maybe our photonics expertise will advance faster than our large scale construction expertise, and we will do all huge telescopes with many mass produced smaller ones. Maybe their relative positioning doesn't even need to be super stable because we can measure it accurately enough and correct for their relative motion. But it is fun to imagine a 1km scale truss system to hold a massive segmented mirror in space. Picture 250,000 mirrors, each 2m in diameter. It will not remove all stresses to be in space. At that scale, you may start to get tidal stresses and thermal stresses that are almost as hard to engineer as wind and gravity stresses on earth. Likely this huge space telescope will require asteroid or moon mining technology and much better robotic construction tools. But it is a much more likely future of massive spacecraft than the km scale star destroyers of Star Wars fame.

Here is Gemini's press release - I didn't see it linked in any of the articles: https://www.gemini.edu/node/12...

My town is home to the base facilities for eight of the Mauna Kea Observatories, and we're looking at the Thirty Meter Telescope in the near future as well. Needless to say, there are pretty much always job openings for engineers, technicians, and PhDs. The catch? We're on an island, and some people get tired of that.

So Science Education/Public Outreach (SE/PO) is a part of life here. Pushing Science, Technology, Engineering and Math (STEM) as good ways to make a better-than-average living is a part of life here. The scientists take over the local mall one day every spring. In late January, we take over the University for a "science day" in honor of Space Shuttle Challenger astronaut Ellison Onizuka, for kids in grades 3-8, and NASA sends an astronaut each year. And around late February or early March, there's Journey Through The Universe.

I'm actually about to head to a nearby school to spend an hour talking about science careers to a classroom of 7th-graders, so I'm getting a real kick out of this article showing up right now. The other 9 classes I'm visiting over next Monday, Tuesday and Thursday are a bit younger - grades 1-3. The idea, though, is that from Kindergarten on, kids here are meeting real live people who work in science at observatories or other "famous science places" every year and are being encouraged to stay in school, take classes about STEM, look at college majors in STEM, and become qualified for those good jobs, so that we can hire people who are from here and would love to stay here.

Last year, I was told about one of the first success stories - a guy who was in 7th grade when they started visiting classes, and as a result of what he heard over the years, had picked a STEM major at the local university, and was now going to accompany a scientist to classes as a "community ambassador" sort of person.

Here is a link to the press release from Gemini Observatory: http://www.gemini.edu/node/11656

It's not as big as it sounds. Milky Ways only have like 9 grams of fat. So this thing is like... 180 grams of fat. We'll live.

Sure, in a diabetic coma, that's about 10 ounces (280 grams) of sugar. I'd go with the Outback Steakhouse Aussie Cheese Fries with Ranch Dressing... but Chili's Awesome Blossom has more fat... the good stuff always does...

A little closer to topic, to be a cannibal doesn't this thing have to eat OTHER giant "galaxy eating" galaxies? Also, looking at the photo the galaxy in question may be large, but you have to admit it's positively glowing...

Some description of the technique. Under ADI.

On Thursday 13th November 2008, Gemini Observatory in coordination with several institutions released the first images of an exo multi-planet system around star HR 8799 in the constellation of Pegasus. The discovery was made at Gemini North using the adaptive optics system ALTAIR and NIRI as the infrared imager on October 17, 2007. Follow up and confirming observations were made on the Keck II Telescope and Gemini North. Adaptive optics played a crucial role in obtaining these historic images of a young extra-solar multiple-planet system. The estimated age of the system implies planetary masses between 5 and 13 times that of Jupiter. These giant planets orbit at roughly 25, 40 and 70 times the Earth-Sun separation around their host star which is about 128 light-years from our sun. For more details see www.gemini.edu.

The discovery was made using the 8m diameter Gemini Telescope - North on Mauna Kea. It's doesn't have Hubble's advantage of being in space, and so a clever approach is employed to eliminate interference from atmospheric turbulence. A laser is used to induce fluorescence in the sodium layer left by meteors up around 80 km altitude. -- this is called a "guide star" -- and adaptive (i.e., deformable) optics in the telescope bring the guide star image into sharp focus, and the rest of the scene with it. A guide star is used for this process rather than an actual star because it is much easier to adaptively image a bright object (which can also be positioned where needed). Such a clear image would otherwise not have been possible.

In case anyone is inerested, here is a link to the article on Gemini's website:

http://www.gemini.edu/index.php?option=content&task=view&id=284

There are a couple good pictures available.

Indeed. Cerro Pachon is at 30 degrees south, in central Chile, meaning that a fair portion of the northern sky won't be visible.

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.

It just says that the light wouldn't be as intense as in the cases where people have gotten in trouble with their laser pointers.

That seems a little hard to believe at first, since a green laser pointer's power is only something in the milliwatts, and the AOPA article mentioned in another reply (this is a fixed URL, incidentally) talks about a 1.5 watt laser. But that's reflected/diffused to create a 100-foot-wide line of light in a circle 10 miles from the laser, so I guess by sending the light off in all directions (not at all like your normal use of a laser) it's possible that it wouldn't be a problem.

Out here in Hawaii, the summit of Mauna Kea is an "informal" no-fly zone. There aren't any major flight paths that would cross it anyway, and since there are telescopes on it, folks have basically just agreed not to go flying over when we're trying to see things.

This has become a little more important in recent years, since the folks over at Keck use a laser to ionize stuff in the sodium layer of the atmosphere and create an artificial "guide star" that they can then measure the light from to correct for atmospheric interference. This is part of their adaptive optics, I think. That's a 15-watt laser, which could really ruin a pilot's day.

And Gemini North, across the summit from Keck, is about to start playing with a big bright toy too.

They've got a pool of "plane spotters" who spend half a night standing outside on the summit with a walkie-talkie. If they see any planes that look like they might get in the way, they radio in to turn off the laser before anything gets zapped.

I'm going to try to do that, one of these days. Goodness knows I'm up there enough as it is.

It's not too big to be a supergiant planet. It's the same size as jupiter.

Safety may be the main reason but it was always risky to do work in space. Perhaps we understand the risk better now and have rethought our risk:reward ratio. Comments on other points:

The Hubble wasn't state of the art when it was launched. Nothing launched is state of the art; by the time it is designed and built with space-hardened parts, it is already out of date, not to mention the actual delay involved in launching and on-orbit activation.

Hubble was flawed when it was launched. Luckily there was a servicing mission or it would have been a practically useless telescope, though today we have deconvolution software which goes a long way toward correcting this and other optical flaws, whether or not you know how it is flawed or camera is moving, etc.

While adaptive optics can compensate for the atmosphere in some ways it cannot compensate in all ways; there are limitations and more limitations, even of multi-conjugate AO. Telescopes in orbit or on the Moon will always have some advantages.

In particular, there seems to have been an agreement made some years ago between whatever entity handles the summit for astronomy (probably the University of Hawaii Institute for Astronomy) and some native groups (mountaintops are sacred places) under which the astronomy folks got permission to build a certain number (int) of telescopes.

That many have now been built. The astronomy folks would like to build more. And... various folks (natives and others) are noting that um, no, that's not what they agreed to. So there's been a lot of paperwork, environmental impact statements, and so on.

In some cases, things are a little grey-area-ish. They want to build "outriggers" on the sides of the Keck scopes, for example. And the Smithsonian-Sinica.tw-Harvard submillimetre array - does that count as 8 scopes, since there are 8 dishes, or 1, since it's an interferometer?

As it now stands, though, Mauna Kea wins lots of astronomy pissing matches. :) It has the 2 largest optical scopes in the world (Keck and Keck II), plus the 4th largest (Subaru) and another in the top 10 (Gemini North), the largest single submillimeter telescope (James Clerk Maxwell) and I think the largest dedicated infrared telescope (UKIRT).

If someone wanted to build a truly monster scope on Mauna Kea, they could simply remove one of the small ones, it would seem. University of Hawaii has an 0.6-metre one and a 2.2-metre one. (Yes, those are "small," all you backyard astronomers who are now drooling. ;) Take out the 0.6 and replace it with a 30-metre one, and you haven't changed the number of telescopes, right?

According to the Beeb, ground-based telescopes are catching up, referring to the Gemini observatory.

The technology used by this telescope to counter the effects of the atmosphere in measurements is called adaptive optics. This is the first application I know of for adaptive optics on a solar telescope.

This technology has been around for awhile, and was first seriously developed by the military at the Starfire Optical Range .

Recently it has been used in such telescope projects as the WM Keck Observatory and Gemini Project . I know AO is also used for measurement of eye aberrations, with projects being conducted at several Universities. For more information about Adaptive Optics, I suggest the Center for Adaptive Optics

My personal experience with AO was as an intern for Gemini this past summer. I helped write parallel code for a program that simulates current and future adaptive optics systems planned for the next generation of extremely large telescopes.

right here

It is worthwhile to note that the internet link is a separate issue from the sharpness. All the internet link does is allow researchers to use the scopes and return a lot of data quickly, reducing the need to travel to the telescope to observe with it. All of astronomy is moving in this direction, because these very expensive instruments must be utilized efficiently.

The sharpness of this scope comes from the very large mirror (8 meters) and the adaptive optics installed on it. The photos would be just as sharp even without the internet connection.

I'm so incredibly lazy, and I guess there's more like me out there...

http://astra.hi.gemini.edu/gallery/science/

Someone needs to mod the above up; it's important. I would have rephrased the post to reflect that this was NOT the first image of a brown dwarf orbiting a star if I knew about it before I submitted the comment.

On closer examination, the Gemini North press release does not claim to be the first to image a brown dwarf; from the site:"The faint companion is separated from its parent star by less than the distance between the Sun and the planet Uranus and is the smallest separation brown dwarf companion seen with direct imaging". It is only the CNN story that incorrectly claims this.....Hmmmm perhaps a notification is in order.

Is actually here: http://astra.hi.gemini.edu/gallery/science/m87/

They're not just looking at it with red, green and blue CCD sensors -- Imaging Spectrometers give you a readout of the full spectrum, including characteristic bright (emission) and dark (absorption) lines. The position of these lines in the spectrum changes with distance (red shift due to expansion of the universe) which looks a lot different from just a naturally red star. In fact their estimate of the age of the galaxy is based mainly on how far the lines have shifted!

Well, Hubble is a great project that brings us nice images of the space and etc..., but it is now outdated technology. with the advent of adaptive optics It is now easy to get images as neat as those photographied by Hubble, and even better, from the earth.

The advantages being that since it is based on the ground, it is much, much cheaper. No need to send Shuttles in the space or on the moon... Of course it is less spectacular, but it is better for Science. It is currently being installed on the European Space observatory at least.

But the next leap forward is going to be European... ESO (European Southern Observatory) are constructing two identical telescopes in Chile and Hawaii (project Gemini.) How's that for a long baseline? ;p

And for bluesky "gee whizz" quotient, check out the Overwhelmingly Large Telescope (OWL)...

I've seen a chart somewhere (can't find a link - anyone?) charting aperture (light collecting capacity) of telescopes since Galileo. The Keck and other 10m class telescopes have moved the curve from a nice straight line to an exponetial curve - and that's not allowing for vastly increased computer power, active optics, and out-of-visible band stuff. Truly this is a fantastic time to be interested in astronomy, even (especially?) as an amateur. For a couple of thousand dollars you can do stuff in your yard that was the province of professionals only a few decades ago.
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If the good lord had meant me to live in Los Angeles

But the next leap forward is going to be European... ESO (European Southern Observatory) are constructing two identical telescopes in Chile and Hawaii (project Gemini.) How's that for a long baseline? ;p

And for bluesky "gee whizz" quotient, check out the Overwhelmingly Large Telescope (OWL)...

I've seen a chart somewhere (can't find a link - anyone?) charting aperture (light collecting capacity) of telescopes since Galileo. The Keck and other 10m class telescopes have moved the curve from a nice straight line to an exponetial curve - and that's not allowing for vastly increased computer power, active optics, and out-of-visible band stuff. Truly this is a fantastic time to be interested in astronomy, even (especially?) as an amateur. For a couple of thousand dollars you can do stuff in your yard that was the province of professionals only a few decades ago.
--
If the good lord had meant me to live in Los Angeles

These calculations have been done, and the result is that the best achievable resolution is on the order of 10 centimeters. Enough to read tail numbers on airplanes, not enough to read license plates or newspapers.

Not so fast.

Astronomers have found a way to overcome the atmosphere's turbulence: adaptive optics. If I recall correctly, they shine a laser upwards to create an artificial star, and then by monitoring the twinkling of the artificial star, the telescope mirror is dynamically distorted hundreds of times per second to compensate.

Such a mirror is now in place at Mauna Kea... the resolution rivals Hubble's, at a fraction of the cost. See Gemini North Sees the Light (scroll down to "Friday, June 25"), or the media fact sheet from the Gemini Project.

See also this picture of Pluto and Charon.

Now, the question is: can adaptive optics be used in the other direction, to observe the ground from space?

Did astronomers actually invent adaptive optics, or is it just another Cold War technology spinoff? Makes you go Hmmmmm.....