Closure Looms for Keck Interferometer

Early on February 11th, as dawn's rosy glow enveloped the summit of Mauna Kea in Hawaii, the domes of the Keck telescopes slid shut after a long night of observing. It had been a great run for Gerard van Belle (Lowell Observatory) and his small team. They'd used the two giant eyes together, pointing them in tandem at a handful of dim, cool dwarf stars scattered across the Hawaiian sky.

Keck's twin telescopes
Light from the Keck Observatory's twin 33-foot (10-m) telescopes can be combined to create the world's most sensitive optical interferometer. But funding for the system will end in mid-2012.
NASA / R. Wainscoat
By carefully combining light beams from both telescopes, the observers had effectively transformed the two 33-foot-wide (10-m) primary mirrors into a single, much larger aperture 280 feet (85 m) across. This powerful pairing, called an interferometer, can discern the shape of a grape from 1,000 miles away. It enabled van Belle to resolve the disks of a few of his target stars — a feat not possible anywhere else.

Unfortunately, last week's all-nighter will be his team's final chance to harness the telescopes together. Last summer NASA managers quietly decided to stop funding the interferometer, and it will be mothballed in July. After that, the two Keck telescopes — which had been designed from the get-go to work together — will stare into the cosmic depths on completely separate schedules.

NASA's official position is that the interferometer has completed its primary task of revealing dusty disks surrounding nearby stars. Moreover, it's complicated and expensive to link the giant eyes through a system of optical pathways for just a few dozen nights each year. "This is tremendously bittersweet to me," van Belle laments. "I spent hundreds of nights on the summit from 1998 to 2001 getting this system to work."

Plan for Keck outriggers
Astronomers had planned to add four "outrigger" telescopes, each with 6-foot (1.8-m) apertures, to the existing Keck telescopes.
M. Colavita / P. Wizinowich
For all its success, the Keck Interferometer has never lived up to its full potential. That's because it lacks a quartet of smaller telescopes, each with a 6-foot (1.8-m) primary mirror, that were to be installed alongside the towering twin domes atop Mauna Kea. These four "outriggers" would have given the interferometer the ability to image small patches of sky with unprecedented resolution — down to 30 micro-arcseconds, according to project scientist Rachel Akeson (Jet Propulsion Laboratory) — sufficient to spot Uranus-size planets circling nearby stars. It was designed to be the world's most powerful optical interferometer.

NASA gave the project a green light and funding in 1998. EOS Technologies in Tucson, Arizona, built the four telescopes years ago at a cost of about $15 million. But they never made it to the summit, victims of a sociopolitical struggle in Hawaii and NASA's shifting priorities in faraway Washington.

Island Tensions

Mauna Kea, often translated as "White Mountain" because it's sometimes capped with snow, is a massive but dormant volcanic peak that rises 13,796 feet (4,205 m) from the Pacific Ocean. It provides what is arguably the premier site in the world for astronomical observations.

But it is also sacred to the Hawaiian people, and the stark, other-worldly summit — known locally as wao akua ("realm of the gods") is dotted with shrines, altars, and hidden burial grounds. Although professional astronomy is a strong driver of the Big Island's economy, lots of Hawaiians are nonetheless unhappy about having their sacred mountain peppered with gleaming observatory domes.

"Outrigger" for Keck Interferometer
One of four "outrigger" telescopes and its co-rotating enclosure that were to be installed as part of the ill-fated Keck Interferometer.
EOS Technologies
Tensions between the Big Island's native inhabitants and the University of Hawaii, which manages Mauna Kea's observatory complex, have simmered and occasionally boiled over for decades.

A master plan, approved in 1983, allows for no more than the 13 domes that exist there now. Whereas astronomers saw the outriggers as a extension of the existing facility, and thus part of Keck's two-dome footprint, native and environmental groups saw them as a cap-busting series of new structures. A revised master plan, agreed to in 2000 by the University of Hawaii and the Office of Hawaiian Affairs, would have permitted the construction of up to six Keck outriggers, but opponents challenged NASA's environmental assessment for the project.

The beginning of the end came in 2006. First, NASA withdrew its funding for the outriggers. The space agency had hoped to use the full-up interferometer as a pathfinder for two future efforts called Space Interferometry Mission and Terrestrial Planet Finder. But when these expensive, challenging missions foundered, so did enthusiasm for the funding Keck's interferometer.

The second and final straw followed a few months later, when a judge ruled that the expansion permitted by the revised master plan — and construction of the Keck outriggers in particular — could not go forward until a comprehensive assessment addressed environmental concerns for the entire summit. With funding withdrawn and a long legal battle looming, project proponents retreated.

NASA continued to fund the interferometer that linked the existing Keck telescopes, but the facility's scientific utility had been crippled. "The decision [to end funding] has been coming for years," Akeson explains. "The reality is that the interferometer has had to compete against all the other capabilities of Keck, and it requires the use of both telescopes."

Navy Optical Interferometer
The Navy Optical Interferometer sits atop Anderson Mesa near Flagstaff, Arizona. Its Y-shaped array permits two-dimensional imaging of the sky at very high angular resolution. Click here for a larger view.
Lowell Observatory
A Second Chance?

Despite all the drama and disappointment, the effort and money expended on the outriggers might not go to waste. Keck officials have already turned the telescopes over to the U.S. Naval Observatory, which hopes to integrate them into its existing Navy Optical Interferometer in northern Arizona.

According to program director Don Hutter, adding the Keck cast-offs would be a huge boon to the NOI, which currently has seven telescopes with 20-inch (0.5-m) apertures in a Y-shaped array. If the Navy provides funding (and a decision on that is imminent), the NOI could be expanded from its current 80-m baseline to 100 m in just two years, improving its current 0.5-milliarcsecond resolution by a factor of two or three. Eventually the baseline could grow to 437 m — which would make NOI the world's largest optical interferometer.

In fact, van Belle has already hedged his bets. He recently left the Very Large Telescope Interferometer, close competition for Keck, and joined the staff of Lowell Observatory, which manages the Anderson Mesa site on which the NOI sits.

One last point: For a behind-the-scenes taste of Keck operations, be sure to check out Andrew Cooper's "Keck in Motion" time-lapse video, which includes shots of the interferometer's optical components running back and forth on precision rails. Cooper is an engineer, photographer, amateur astronomer, and telescope maker who lives and works on Mauna Kea.

23 thoughts on “Closure Looms for Keck Interferometer

  1. crite40

    Well, once again we see another example of modern decadence.
    The "sacredness" of the volcano is a distorted relic of a very simple mibnded religion (as almost all are).
    So, here we have the world’s biggest telescopes with one hand tied behind their back. Not being set up as intended. While
    billions are still being spent on th Webb space telescope which I forsee will never be a success. Just imagine a crook mirror like the Hubble with a scope you have no way of reaching.
    What the US needs most is a viable way of simply reaching orbit with manned spacecraft.
    How ironical to see the only US astronauts reaching the ISS on Russian rockets which are the same basic design as used in the 1960’s!

  2. Anthony Barreiro

    While I am disappointed that the four additional 1.8 meter telescopes will not be added to the Keck interferometer, and that the existing interferometer will be shut down, I do not believe it is helpful to denigrate the beliefs or motives of the opponents of the expansion. We live in a big complicated world with lots of people with different perspectives and priorities. Mutual respect and collaboration are generally the best approach in such a world. Social values like freedom of religion, due process, and environmental protection have allowed science to thrive in our modern society. Occasionally these same social norms result in scientific projects not moving forward.

    In any event, the Hawai’ian activists are not responsible for shutting down the Keck interferometer — that was ultimately a NASA funding decision. I hope that the new telescopes will find a good home in Arizona, and that the NOI will contribute new knowledge of the cosmos.

  3. Russ

    There seems to be no end to the very highest of American technology & sciences.. that are, item by item, being ‘switched-off’.. so to speak. No, it is MUCH worse than that. If they were merely ‘switched-off’ that would mean they could just as easily be.. ‘switched’ right back on. Do you realize how very far we have been dragged DOWN..? Can you really believe this..? Can anyone imagine if we still had our magnificent Saturn V’s..? Or if we had completed the SSC..? And our Shuttle.. how could that be just dumped. With NO secondary way to send our people into space – up to (mostly) the ISS..? How long before that is abandoned..? Hubble – almost dead. When will Arecibo go..? They tried.. and how many other scientific endeavors are trashed – thrown away. Remember Skylab..? It was wonderful. We had 2 of them.

    Science – our very country.. is under ATTACK..!!! We are so very weakened. Even the SR-71 was trashed. It was also a research capable vehicle. I am flabbergasted. Beyond able to respond in a coherent methodical way. Our nation, like Russia and Germany.. et al.. the Roman Empire.. Greece. Recall the wonderful Library at Alexandria. Oh well.. easy come..

  4. aholmgren

    The decline of American science continues. Retiring the Shuttle fleet, the shutdown of the Tevetron and now the Keck interferometer closing is really depressing. The brain drain is the worst of it. High energy physics is now happening at the LHC and now our best astronomers are going to have to go to Chili to continue their studies. This is not encouraging news for our graduate students and post docs.

  5. Citizen

    Ever heard of any other telescopes called "outriggers?"
    Project advocates co-opted the word from Polynesian canoe design to make the project seem more palatable to the local community. It didn’t work.
    Astronomers have never done as good a job of gaining community support as they have in research. I hope the instrument finds a happy home on the mainland. (And I wouldn’t bet serious money on the TMT being built on Mauna Kea. The people opposing it have learned their legal strategy from the successful scuttling of the outriggers.

  6. crite40

    It was very interesting to see many other comments on the decline of US (in particular) science.
    As to belief systems. Well it is a question of real social responsibility by all. Far too many ,most in fact, religions
    whether Polynesian, Middle eastern, or European show NO sense of social responsibility at all.

    In the end you do nothing, jus because you are terrified to question belief systems.
    Whatever happened to Galileo and Bruno??

    I belong to a minority religion myself, but my beliefs are always under question as we find out more about the universe.

  7. NS

    To borrow a religious saying, get the plank out of your own eye before you worry about the mote in your neighbors’. Science (and much else) in the U.S. is declining because our country is controlled by a small number of people who care only about piling up wealth for themselves, most of it derived from playing games with money that not only don’t benefit most of us but are actually harmful. Take care of that and there’ll be plenty of money for science and a lot of other things that need doing.

  8. Richard

    But there is still lots of money for the orbiting white elephant, the ISS and plenty of money for NASA to pursue their new business venture, propping up global warming theory. Meanwhile, planetary exploration and astronomy get gutted.

  9. Cybermystic

    It is very strange that the Polynesians who so revered the stars would not be fully supportive of structures to study them. Placing these structures on a high sacred mount would seem to be apt rather than an act of desecration. I would guess there must be more to their negative attitude to observatories on Mauna Kea – and that someone, somewhere along the road has thoroughly cheesed the locals off.

  10. Toyscientist

    It’s needless to point fingers at indiginous religeons. This is all about money which as we know has purchased USA anything it wants. It’s actually refreshing that the reason might be tied to local spirtitual belief. How sensitive America has become. But no, if the money had been there, those Hawaiians would have gladly taken the lucre and we’d have our wonderful interferometer.
    Tough times. My hope spend on people and science instead of war.

  11. george b

    According to the article and the links, the main "religious" blockaded came not from Hawai’ian or Polynesian religious believers but rather from the modern, pseude-scientific, quasi-religious environmental movement. Litigation and environmental impact study costs were the ultimate undoing of the project. It is not possible to plan or budget for future activities in the shadow of such unpredictable and potentially endless threats.

    Then, combine that with the massive and growing costs of maintaining the welfare state, one can expect to see many more cancellations of important but "discretionary" projects, especially from NASA. The space shuttle. ISS funding after 2020. US manned space flight. Future flagship unmanned space missions. They all have been or will be cut or canceled.

    Somewhere between the excesses of the past and the excesses of the present, there has to be a middle ground.

  12. Rodney Austin

    At the end of the day, the outriggers will be better off on Anderson Mesa. A dedicated interferometer is better than an ad hoc system using telescope which are better utilised for deep space observations. But it is a sign of the politically correct times unfortunately.

  13. Jim Quinn

    This story is a very sad chapter in the continuing story of first-class scientific efforts closing because of lack of funding. I find it hard to believe that such an important part of Keck’s raison d’ etre is fading into the past.

    As always, Kelly Beatty has written a great article that tells us far more than I could have learned anywhere else. Does anyone know if the interferometers built down in the Atacama Desert are as good or better than the Keck? I got the impression that the ESO plan was expected to yield some incredible results, but I never got enough details to know how it’s going.

    Hey, I’ve got an idea! Since Arecibo is also doomed, let’s lease it for $1 and turn it into the gnarliest skate board park in the galaxy. We could make enough in admissions to pay for some really amped science, dudes.

  14. Jeff

    >Far too many ,most in fact, religions whether Polynesian, Middle eastern, or
    >European show NO sense of social responsibility at all. In the end you do
    > nothing, jus because you are terrified to question belief systems.

    Science is not a belief system. It is a process to identify, and self-correct, fact from hypothesis. Religion, regardless of whom’s is not based on anything other than myth and belief. Science will lead us into the future. Religion will lead us to fear, hatred, and ignorance. Religion throughout history NEVER has moved science forward until someone or something comes along to force it to move.

    Social responsibility has nothing to do with religion. I can be caring, a good steward of the land, and a contributor to society, any society, all without religion. We’ve got the brain power to move beyond. And we should.

    At least I hope so.

  15. Tony Flanders

    Sorry, Jeff. The statement that religion has never advanced science is demonstrably false — consider for instance the Islamic advances in astronomy during the Middle Ages. And while science is not a belief system, scientism — the claim that all of reality can be reduced to scientific observation and theory — most definitely is a belief system, and a pretty shaky one at that. As for whether science is necessarily onward, upward, and all for the best — what about Hiroshima? The rights and wrongs of Mauna Kea are very complex. No single interest group has total claim on this truly unique piece of real estate.

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