Getting straight to the point, last week we finally installed the test camera onto the telescope! A huge milestone for the project, although it really should be called a kilometerstone since we’re in Chile. Minor quibbles.

This smaller camera is called the Commissioning Camera, or ComCam for short. “Smaller” isn’t the best terminology because ComCam is the same volume and weight as the real LSST Camera. However, it has only nine sensors, making it a measly 144 megapixel camera instead of the 3200 megapixels that will be available on the real camera.

The Commissioning Camera (ComCam) on the maintenance level of the observatory, just before being brought up to the telescope for installation

2 hours of work summarized in 15 seconds

The installation process itself is fairly straightforward but takes a long time since everything has to be done slowly and quadruple-checked. With the telescope horizon-pointing (i.e. tilted 90 degreed, or all the way sideways, such that the top end is now on the side), the entire teal/black assembly gets lifted by a tall yellow lift fixture and then carefully threaded into a cylindrical opening in the top end of the telescope. There are some guide rails for the first part of the installation but the tight clearances are mostly controlled by a skilled crane operator and some technicians up on scaffolding.

It’s an exciting achievement because now we can actually start testing utilities on the telescope, and the data pipeline, and controls software, and a myriad of other things that go into running an instrument. Once the mirrors are installed early next year we can also take our first photos of the sky, although the official “first light” won’t happen until the real camera is installed at the end of next year. Assuming the schedule holds. Which … isn’t the best assumption based on our current track record. Turns out making a one-of-a-kind state-of-the-art camera, telescope, and observatory is hard.