Mauna Kea--cloudless, no city lights, and astronomers love it
The Summit of Mauna Kea, Hawaii — From the top of Mauna Kea, man is exploring the universe.
Here, nearly 14,000 feet above the blue ocean that stretches away for thousands of miles, is the highest point in the Pacific Basin: a dormant, snow-mantled volcano that, in the past decade, has become one of astronomy's most sought-after sites for observing the night skies.
Twenty years ago, this barren, lava-strewn summit--which looks more like the surface of Mars than a tropical island--was an astronomical unknown. Today, six telescopes, involving the efforts of four countries, scan the universe from here--and attract astronomers from around the world, who consider an opportunity to view the stars from Mauna Kea to be an unparalled scientific plum.
''Everyone now planning to build a large telescope would like to build on Mauna Kea,'' says Rene Racine, executive director of the $30 million, 144-inch Canada-France-Hawaii Telescope, which began operating in 1979. ''We have the clearest view on Earth.''
Ironically, though, the US government itself is considering withdrawing some of its support from Mauna Kea's astronomical outpost. Pinched by budget demands , the National Aeronautics and Space Administration may cut off funds for its infrared telescope atop the volcano. There is a chance, however, that a group of universities or other institutions may pick up the funding for the instrument, considered by scientists to be one of the finest of its kind.
''Mauna Kea is almost halfway above the Earth's atmosphere, which means it's almost halfway to space,'' Mr. Racine points out. ''We can do things here that will only be beaten by telescopes that are put into orbit in space.''
What makes Mauna Kea such a highly favorable site is its dry, cloud-free atmosphere, which means that the proportion of clear nights at the summit is among the highest in the world. In addition, the stability of the atmosphere allows astronomers to make highly detailed studies of the star and planets. Also , because there are no nearby urban areas to reflect city lights into the atmosphere, the sky here is especially dark, which allows observation of objects that lie at the farthest edges of the universe. And because of the volcano's proximity to the equator, astronomers can view most of the night sky at any time of the year.
Astronomers who wish to use one of the Mauna Kea telescopes must make an application to the scientific committees that oversee scheduling for the telescopes every six months.
Because three to four times the number of astronomers that can be accommodated request observation time, applicants' scientific proposals are weighed carefully. ''Is it on the frontier of astronomy? That is the main question we ask,'' explains Mr. Racine. ''Also, we ask 'Can it be done at another telescope?' We only allow what can only be done here.''
Astronomers do not have to pay to use the telescopes, which are maintained and run by the governments involved at a cost of between $2,000 and $8,000 per night. Usually, they are granted three to nine nights of viewing time--and must hope that those nights are not one of Mauna Kea's few cloudy nights. Time is not rescheduled because of weather.
Mauna Kea, however, has not always been in such demand. It was not even considered as an observatory site until 1963, when Gerard P. Kuiper, who has been called the father of modern planetary astronomy, first scouted it out. After months of site testing, he has been quoted as saying: ''The mountaintop is probably the best site in the world--I repeat--in the world, from which to study the moon, the planets, and the stars.''
In the early 1970s, the volcano site received a major boost in credibility when the French government, in partnership with Canada and the University of Hawaii, decided to build a 144-inch telescope--the sixth largest in the world--on the summit.
Two infrared telescopes, and two smaller telescopes which began operating in the late 1960s, brought the number of telescopes on Mauna Kea to six--and made it the largest observatory in the world in terms of total light-collecting area (measured by the size of a telescope's mirror).
Currently, three applications are being considered to build radio telescopes on Mauna Kea. In addition, the University of California, which plans to build a 10-meter telescope that would be the largest in the world, is said to be eyeing the volcano summit as a potential site.