In February 2008 we were in Hawaii on the Big Island and took the opportunity to visit the Mauna Kea summit and the telescopes there. The altitude is 13,800 feet and the climate is about as different from sea level Hawaii as you can imagine. The air is rather thin, there's no jungle vegetation and the overall landscape is more desert than jungle. There's snow on the top and Mauna Kea has the unique distinction of having the only snow plow in Hawaii.

In recent years the peak has been home to some of the world's largest telescopes and besides the telescopes it is a special place to visit. It's revered as the place of origin of the Hawaiian people and it is also a dry and high location ideal for optical astronomy. The presence of telescopes in this sacred area has caused some conflict over the years and at the moment there is something of a detente between the astronomers and the native Hawaiians.

The summit consists of several different telescopes operated by several different organizations. The entire area is administered by the University of Hawaii. For more details see the links at the end of this page.

Because of the altitude and access restrictions we opted for a guided tour. Even if we could have driven up by ourselves we wouldn't have done it. By the time we got the top we were suffering from hypoxia and it was hard to do anything much more than put one foot in front of the other. Our tour began in the morning and included lunch, a visit to the summit, seeing the sunset, and finally returning to the visitor center which is at about 9,000 feet. There we had a chance to do some observing with portable telescopes that our guide brought along. The seeing in this area is just spectacular, even at the lower altitudes and with smaller telescopes. It's easy to see why this is a productive spot for astronomy.

On the way up we stopped for lunch at this abandoned ranch. I don't recall the altitude but it helped with acclimation.	Here's our van and the visitor center where we stopped on the way up and the way down. On the downward trip the center was bathed in red light so as to keep our dark adaptation for the small telescope viewing.
Our intrepid guide standing next to some endangered flora. The fencing keeps local critters away from the plants. You can see how this area looks a lot more like desert than jungle.
	You know you're up high when you can look down on the clouds.
Ah, our first view of the telescope buildings. I thought we left snow behind in Vermont.	We didn't get a chance to get inside any of the domes to see the instruments. Bummer. I think that's the Subaru telescope on the left and the two Keck telescopes on the right.
	Driveway markers?!
This is the point where oxygen deprivation started to hit me. I don't remember taking this picture.	Sunset is starting.

Links:

The Keck telescopes

An overall summary of astronomy at the peak from the University of Hawaii

Another overview of Mauna Kea from Wikipedia