The sun is setting over the luxury resorts of Kona, on Hawaii's Big Island. Warm tropical breezes waft lazily through the palms. Honeymooning couples sip mai tais by the pool as waves break gently on white sand.
Just 30 miles inland, conditions aren't quite so pleasant. The sunset is every bit as gorgeous from here, at the summit of the long-dormant volcano Mauna Kea, but temperatures hover around 38[degrees]F, with a windchill that dips well below freezing. At an altitude of nearly 14,000 ft., the atmosphere carries barely half the oxygen it does at sea level, so the slightest exertion can leave visitors gasping. Those who travel to the summit without getting properly acclimated risk altitude sickness and even death.
But with night skies that rank among the clearest and darkest on Earth, Mauna Kea offers an unsurpassed view of the heavens--and that's why, despite the harsh conditions, astronomers can't wait to visit. Stargazers come here from around the world to answer some of the deepest mysteries of the cosmos: When in the depths of time did galaxies first flare into existence, and what made it happen? What is the elusive dark matter whose mass dominates the universe? How many stars have planets--and do those alien worlds harbor intelligent life?
These questions and more have tantalized astronomers for decades--and Mauna Kea is one of the few places where answers may finally be found. The mountain is dotted with white and silver observatory domes, sprouting like oversize mushrooms from the barren, rocky rubble that was once molten lava and, much later, a holy place of the native Hawaiian people. And although it's not obvious to the casual visitor, these domes conceal stargazing machines of unprecedented power.
For nearly a half-century, starting in 1949, the world's most powerful research-quality telescope was the Hale, on Palomar Mountain, in California. Its mirror, 5 m (17 ft.) in diameter, focused more faint starlight than anything else on the planet. But in the past few years, the Hale has been humbled. Here on Mauna Kea alone sit the Subaru telescope (no relation to the car), with a mirror more than 8 m (27 ft.) across; the Gemini North telescope, also topping 8 m; and the kings of the mountain, the twin Keck telescopes, whose light-gathering surfaces are an astonishing 10 m--33 ft.--in diameter.
The story is the same all over the world. In the high Andes of northern Chile, five more 8-m-class telescopes are either finished or nearing completion, while peaks in Arizona, Texas and South Africa too boast scopes more powerful than anything known to science just a decade ago.
That's not all. While each of these instruments trumps the Hale in light-gathering power, many are poised to outshine even the Hubble Space Telescope, which has been delivering astonishing snapshots of deepest space since it was refurbished in 1993. The orbiting observatory's nearly 2.5-m (8-ft.) mirror isn't all that powerful, but since it floats above Earth's constantly roiling atmosphere, the Hubble has been unrivaled in the sharpness of its images. No more. Using an ingenious technological trick to eliminate atmospheric blur, most of the new telescopes will soon achieve Hubble-quality focus--and even beat it under the right conditions.