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Three weeks ago, SCUBA-2 arrived in Hilo. Today, after putting it on the back of a truck and hauling it up Mauna Kea, the cryostat was successfully lifted into JCMT!

While this may not sound like that big a deal, for SCUBA-2 it is. Most astronomical instruments have cryostats that are relatively small, maybe a few cubic feet, and they typically get cooled with liquid nitrogen to temperatures in the tens of Kelvins (remember, zero Kelvin is absolute zero, or 273 degrees Celsius below zero, or 459 degrees Fahrenheit below zero). SCUBA-2’s cryostat is huge! It’s about 2.5 cubic meters (about 90 cubic feet) and weighs about 2500 kilograms (5500 pounds)!

Let’s put that another way: a typical hot tub holds about 450 gallons of water, which is about 1700 liters. 1700 liters is 1.7 cubic meters. SCUBA-2 is 2.5 cubic meters — larger than your typical hot tub. This happy coincidence wasn’t lost on the SCUBA-2 designers, as there’s a CAD drawing of the SCUBA-2 cryostat with four humans sitting inside it. SCUBA-2, the hot tub instrument!

And get this: the entire thing is cooled to four degrees above absolute zero!

To get the cryostat into JCMT, they had to roll back the protective Gore-Tex membrane, tip the dish over on its side, and use a giant crane to lift the cryostat in. This was a major effort and kudos to everybody involved!

Jonathan Kemp took a bunch of pictures of the installation. This pulled-back shot shows what I described in the previous paragraph — the membrane is rolled back, the dish is tipped over, and the crane is lifting the blue SCUBA-2 cryostat into place. This picture shows the scale quite nicely — compare the men to the blue cryostat. It’s huge!