Hawaii is one of the world’s best places for stargazing. There are many stargazing options you can fit in your itinerary on the Big Island; from a (free) nighttime picnic to an adventurous visit to the world class telescopes on the summit of Mauna Kea. It is no coincidence that some of the worlds most advanced telescopes are build on the Big Island. Few places on earth are better for watching the heavens above than atop Mauna Kea! On top of the mountain above the clouds, observing conditions are close to perfect, with almost no light pollution and little air above.

To the native Hawaiians, the summit of Mauna Kea is a very sacred place. It is the place where their gods live – it is their “heaven”. If you decide to make the visit, please be respectful!

Going to Mauna Kea | Plan your trip yourself | Join a Tour | Health hazards

Telescopes on the summit of Mauna Kea

A visit to the Big Island is not complete without some serious stargazing, and it is very easy to fit it in your schedule. The drive to Mauna Kea takes you over the Saddle road, that connects Kona and Hilo. There is the possibility to visit the telescopes during the day, but your most spectacular option is to visit the summit during sunset! You will see the sun dip below the clouds in a spectacular explosion of color, framed by (snowy) peaks, old volcanoes and futuristic telescopes.

Before reading on, please be aware that the peak of Mauna Kea is 13796 ft above sea level. Because the oxygen level in the air is so low, it is heavily recommended to pause an hour halfway the peak to acclimatize. Even then, it is possible you will experience altitude sickness on your way to the top. If that happens, drive back to sea level immediately! (back to top)

Watching the sunset from the summit of Mauna Kea shows yet another (very cold) face of the Big Island

How to plan your trip to the summit

There are several possibilities to visit the peak of Mauna Kea. [1] With your own transport, and [2], with an organized tour. In any case, you will have to make a stop halfway at the Onizuka Center for International Astronomy. This is the support station and visitor center for the telescopes on Mauna Kea, and is named after the Hawaiʻi-born astronaut Ellison Onizuka, who died in the Space Shuttle Challenger disaster in 1986.

The center shows a video about astronomy and has a small souvenir shop with many good souvenirs. On your way up you can rest here for a while and get your body used to the low oxygen content of the air. If you stop here on your way down at dark, you can watch the stars through two telescopes and under supervision of local volunteer astronomers!

You can reach the Onizuka Center for International Astronomy with any car. However, you need good breaks and a 4WD car to navigate the steep and winding gravel road to the summit! (back to top)

Map with telescopes on the summit of Mauna Kea

[1] Organize your visit yourself

If you are organizing your trip up the mountain yourself, there are a few things you should consider.

1. You will need a 4WD car to drive to the summit of Mauna Kea, but not all 4WD rental agencies allow their cars to be taken up to Mauna Kea! Have a look at Harpers Car Rentals for cars you can take up to the summit. The Onizuka visitor center is reachable with normal (2-wheel drive) cars.
2. You will not be able to ‘look through’ the telescopes on the summit. After dark, the summit is off limits and visitors are expected to head down directly after the sunset.
3. The high altitude carries serious health risks! These are discussed later in this article.
4. If you have been scuba-diving, wait at least 24 hours before going to the summit.
5. Dress warm!! Especially after the sun goes down, temperatures can drop as low as 30 – 40 degrees F!!

Take plenty of water with you and keep drinking, even if you are not thirsty. Take sunscreen.There are free stargazing programs at the visitor center every night of the year between 6 pm and 10 pm, and also escorted summit tours every Saturday and Sunday. During the free stargazing program you will see a video and be able to use any of the telescopes set up outside the visitor center after sunset. The summit tour leaves from the visitor center at 1 pm and lets you see the inside of at least one Mauna Kea observatory! Afterwards you can stay at the summit until sunset and then slowly drive down for the free stargazing program.

Depart on time! Driving times from Hilo or Waimea to the visitor center are about 1 hour, and another 30 to 45 minutes from there to the summit. Take the Saddle Road (Hwy. 200) from Hwy. 190. At Mile marker 28 across from the Hunter’s Check-in station is the unmarked Summit Road Turnoff.  People usually start getting lightheaded after the 9,600-foot marker (about 6 1/4 miles up the Summit Rd.), the site of the last comfort zone and the Onizuka Visitor Information Station. Stop here for a while before continuing up the mountain.

The Onizuka visitor center. Photo credits: Mike neenan

If you do not have a 4WD car, the drive up to the Onizuka Center for International Astronomy is also very worth-while. The drive up Saddle Road offers stunning views and is an attraction on its own. (back to top)

[2] Join a professional tour

If you decide to go on an organized tour, you have very good options. Most operators employ very knowledgeable guides and pack their own telescopes. This means that next to a visit to the summit at sunset, you will get to experience a personal lesson in stargazing from your guide. They also supply arctic parka’s to keep you warm, and snacks and water. Expect to be away for an average of 8 hours. We recommend the professionals of Mauna Kea Summit Adventures because of their extensive, 25+ years experience and respect for local customs and habitats. (back to top)

Health Hazards on Mauna Kea

At the summit elevation of 13,796 feet  the atmospheric pressure is 40 percent less than at sea level. This means that less oxygen is available to the lungs, and that acute mountain sickness is common. Symptoms include: headaches, drowsiness, nausea, shortness of breath, and poor judgment. These symptoms can be lessened by a proper 1 hour acclimatization at the visitor center halfway up the mountain.

High altitudes can also cause the life-threatening conditions pulmonary edema (fluid in the lungs) and cerebral edema (fluid on the brain). Descend immediately if any of these symptoms appears:

• severe headaches,
• vomiting,
• breathing difficulties,
• coughing,
• blue lips or fingernails,
• disorientation,
• extreme drowsiness that may lead to coma.

Further hazards are dehydration, sunburn and eye damage. Take plenty of water and protect your skin and eyes against the intense UV radiation at the summit with sunscreen and sunglasses. (back to top)