Well it finally happened: SCUBA’s successor, SCUBA-2 has been installed on the JCMT in Hawaii. SCUBA stands for Submillimetre Common-User Bolometer Array and the original was a ground breaking instrument that finally allowed astronomers to probe the depths of star-forming regions and distant galaxies. SCUBA-2 will more of the same and then some.
SCUBA-2 can scan the sky much faster than SCUBA and will allow researchers to measure the properties of protoplanetary disks around young stars, amongst other things. Exciting stuff. It is however very big.
Whereas SCUBA was comparable to a hefty water-heater, SCUBA-2 is more like a minivan. Mostly this is because of the cryostat that is required to keep the technology inside SCUBA-2 at a very low temperature. This technology has been developed principally in Edinburgh but also in Cardiff as well a few other places.
I saw SCUBA-2 in Edinburgh in 2006 and noted its large size at the time. When I observed at the JCMT last November (2007) I asked how on Earth they intended to get the the very expensive SCUBA-2 inside the very expensive JCMT without damaging either. The answer gave was that it would be tricky, and now thanks to a series of photos from April 2nd and 3rd I know what they meant.
The full gallery of 600 photos can be found on the Joint Astronomy Centre’s JCMT pages. There is also a fairly large animated GIF file (22MB) if you would like to see the installation in action.

Looks good – about time really!
Actually, it’s not the coolers and the dilution fridge that make SCUBA-2 so big. It’s the cold optics that take up the space; huge cooled mirrors and lots of empty space where the beam bounces back and forth.
And if you think SCUBA-2 is big, look at the designs for some of the ELT instruments…
Another year goes by and still no science. What a waste of time and money. Heads should roll.