The team at Siding Spring Observatory has been busy re-coating the impressive telescope mirrors.

The first mirror to be completed was the two-metre mirror of the Faulkes Telescope, soon followed by the 3.9-metre mirror of the Anglo Australian Telescope (AAT). On 20 September, it was the 2.3-metre mirror of the ANU Advanced Technology Telescope (better known as the 2.3-metre telescope).

Re-coating the mirrors is a big job, involving removal from the telescope, transportation to the AAT, removal of the old coating, preparation of the mirror with special chemical compounds, the re-coating itself, transportation back to the site, re-assembly, re-collimation, and the creation of a new pointing model.

The 2.3m mirror was taken out on the Monday morning, cleaned and re- coated on Tuesday and installed, collimated, and tested on the Wednesday, ready for astronomers to use that night.

Zoe Holcombe was on the team tasked with the intensive job.

“This was a very quick turn-around and a credit to the entire team,” Ms Holcombe said.

“Currently, Siding Spring Observatory has the capacity to do all the mirrors at site, and some from other observatories around Australia and overseas.

“There is an aluminising plant at the United Kingdom Schmidt Telescope and 24” telescope for the smaller mirrors and the big plant at the AAT.

“The AAT mirror gets done every year and is a much more complex task, as it’s so much bigger - so we are given a week to do the whole job and it’s also all hands on deck.

“No one gets out of a job over the week of the AAT mirror re-coating.”

“With staff changes over the last few years it has been a really exciting time and steep learning curve on how to operate the plant at SSO.”

Ms Holcombe and Glenn Murphy have taken it in their stride to be the only ones that understand how they operate.

When the time comes to “fire” the filaments, Ms Holcombe said it’s the most stressful 10 minutes of the whole process.

“A small slip up and this might mean starting all over again the next day,” she said.