Maunakea

Maunakea ("white mountain"), a major attraction for stargazers, offers the antithesis of the typical tropical island experience: freezing temperatures and arctic conditions are common at the summit, and snow can fall year-round. You can even snowboard or ski up here, though you should be in very good shape and a close-to-expert boarder or skier to get down the slopes near the summit and then up again in the thin air—with no lifts.

Winter sports, however, are the least of the reasons that most people visit this starkly beautiful mountain, a dormant volcano. From its base below the ocean's surface to its summit, Maunakea is the tallest island mountain on the planet. It's also home to little Lake Waiau, one of the highest natural lakes in the world.

Maunakea's summit—at 13,796 feet—is the world's best place for viewing the night sky. For this reason, the summit is home to the largest and most productive astronomical observatories in the world—and $1 billion worth of equipment. Research teams from 11 different countries operate 11 telescopes. There are actually 13, but several are being decommissioned now. Decommissioning takes time, so while they aren't doing science, the telescopes are still there. On Maunakea, several telescopes are record holders: the world's largest optical-infrared telescopes (the dual Keck telescopes), the world's largest dedicated infrared telescope (UKIRT), and the largest submillimeter telescope (the JCMT). The still-larger Thirty Meter Telescope (TMT) had been cleared for construction and was slated to open its record-breaking eye to the heavens until it was delayed by protests in 2019. The project's future is unknown, as the mountain transitions to the management of the Maunakea Stewardship Oversight Authority, which includes Native Hawaiians in the dialogue.

Maunakea is tall, but there are higher mountains in the world, so what makes this spot so superb for astronomy? It has more to do with atmosphere than with elevation. A tropical-inversion cloud layer below the summit keeps moisture from the ocean and other atmospheric pollutants down at the lower elevations. As a result, the air around the Maunakea summit is extremely dry, which helps in the measurement of infrared and submillimeter radiation from stars, planets, and other astronomical points of interest. There are also rarely clouds up here; the annual number of clear nights here blows every other place out of the water. In addition, because the mountain is far away from any interfering artificial lights (not a total coincidence—in addition to the fact that the nearest town is nearly 30 miles away, there's an official ordinance limiting certain kinds of streetlights on the island), skies are dark for the astronomers' research. To quote the staff at the observatory, astronomers here are able to "observe the faintest galaxies that lie at the very edge of the observable universe."

Teams from various nations and universities around the world must submit proposals years in advance to get the chance to use the telescopes on Maunakea. They have made major astronomical discoveries, including several about the nature of black holes, super planets, new satellites around Jupiter and Saturn, new Trojans (asteroids that orbit, similar to moons) around Neptune, new moons and rings around Uranus, and new moons around Pluto. Their studies of galaxies are changing the way scientists think about time and the evolution of the universe.

What does all this mean for you? A visit to Maunakea is a chance to see more stars than you've likely ever seen before and an opportunity to learn more about mind-boggling scientific discoveries in the very spot where these discoveries are being made. Only the astronomers, though, are allowed to use the telescopes and other equipment, but the scenery is available to all. (You must leave the summit before dark for your safety.) We recommend going with a licensed summit tour company that takes care of the details.

If you're in Hilo, be sure to visit the Imiloa Astronomy Center. It offers presentations and planetarium films about the mountain and the science being conducted there, as well as exhibits describing the deep knowledge of the heavens possessed by the ancient Hawaiians.