The last software project that Mark worked on, right up until the day that he was too sick to work anymore, was the JWST Exposure Time Calculator (ETC). This is a web application that would be used by all astronomers who want to use the James Webb Space Telescope after its launch, to figure out how much observing time they should ask for in order to do their science.
Mark designed and partially implemented the server, and redesigned part of the web page, before he died in 2015. Since then, we have expanded the server and rewritten part of it, but his basic architecture remains intact.
Yesterday was the proposal deadline for the first year of observations with the Webb Space Telescope. All the astronomers in the world who hoped to be granted time on the Webb had to get their proposals in by 8pm EST on Tuesday Nov 24.
We saw unprecedented load - more than 30,000 calculations on the last day. And the system handled the load.
There were some problems in the last few days, for reasons we don't understand yet. Sometimes messages were backing up in the system instead of being processed until we intervened to fix it. But because of Mark's architecture, the effect of these anomalies was confined to just a few users, instead of slowing down the whole system for everyone.
Thank you, Mark. I so wish you were here to see it.
But the team raised a glass to you, in our post-deadline celebration.