I have arrived at the astronomers residential facility at Hale Pohaku (~2,900m). This is where we sleep when we aren’t observing. There is also a cafeteria, TV room, games room etc. It’s the middle of the night in Hawaii, but I am staying up as long as possible, to try and get my sleep pattern in line with the observing schedule. We spend about 24 hours at the facility to help our bodies acclimatise to the altitude. We come down here to sleep each night as staying on the summit (~4,200m) would increase the risk of getting altitude sickness.
View of Mauna Kea from my hotel in Hilo (where I stayed one night before driving up to the facility). Note the snow on the summit. The telescope domes are just about visible as white blobs on the top.