Highlights
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EARTHQUAKE!!!
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| During a routine check of its positional accuracy, the James Clerk Maxwell Telescope recorded the Hawaiian earthquake ― making the telescope 'The Most Expensive Seismograph in the World', according to Ken Tapping.* |
Just after 7 a.m. on Sunday, October 15th, the Big Island of Hawaii was hit by a massive earthquake. Measuring 6.7 on the Richter scale, it brought down some buildings and damaged others. The Earth shook so vigorously people found it hard to stand.
The epicentre of the earthquake was very close to Mauna Kea, an extinct volcano crowned with some of the most important observatories in the world. Canada has a strong share in three of those observatories: the Canada France Hawaii Telescope, Gemini North (Gemini South is in Chile), and the James Clerk Maxwell Telescope.
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| The earthquake toppled heavy cabinets and damaged ceilings in the CFHT headquarters facility in Waimea. |
These days, the instruments needed to attack the most important astronomical problems are too big, complex and expensive for any individual country to undertake alone. Instead we form multinational partnerships, and then we do all we can to locate those instruments at the very best sites available. Hawaii is probably the best site in the Northern Hemisphere. Mauna Kea offers a high altitude location, well above the messiest parts of the atmosphere, and is surrounded by ocean. The sea temperature does not vary much, which stabilizes the air in contact with it, making it possible for the telescopes to get better images. The investment has paid off; the Canada France Hawaii Telescope and the James Clerk Maxwell Radio Telescopes are contenders for being the most scientifically successful telescopes on Earth!
The Hawaiian Islands are in fact a chain of volcanoes, rising from the floor of the Pacific Ocean. There is a hot spot in the Earth's mantle, where magma rises, forming volcanic islands, and as the movement of the ocean floor carries the islands northward away from the hotspot, a new volcanic island forms. Why would we massively invest in putting some of the most sophisticated and precise instruments we can make in a place liable to hit by earthquakes?
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| At the Canada-France-Hawaii Telescope (CFHT), this photo shows damage to one of the two bearings pushing the roller on the track.* |
A lot of attention went into earthquake-proofing the telescopes, and to a very large extent the work paid off. Despite the severity of the earthquake, the damage was minor and the telescopes are either back in action or close to being so. The dome of the Canada France Hawaii Telescope was derailed and one of the position encoders was crushed. The encoder has been changed and a few bent bolts replaced. The telescope should be back in action by the weekend. On the Gemini Telescope, some bolts were broken but the telescope suffered little other damage. The refrigerators used to keep the ultra-sensitive imaging devices cold were kept running by a diesel generator. Things are being checked and brought back on line carefully. The James Clerk Maxwell Telescope was in the process of having its positional accuracy calibrated when the earthquake hit. The position record shows the earthquake beautifully, making this instrument the most expensive seismograph on the planet. By the time you read this, Mauna Kea will once again be back in action, observing far more dramatic events, fortunately far away.
 Ken Tapping is an astronomer at the National Research Council Herzberg Institute of Astrophysics (NRC-HIA), and is based at the Dominion Radio Astrophysical Observatory, Penticton, BC, V2A 6J9 Tel (250) 493-2277, Fax (250) 493-7767,
E-mail: ken.tapping@nrc-cnrc.gc.ca
*Photos courtesy of the Canada-France-Hawaii Telescope.
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