On Saturday I gave the after dinner talk at the British Astronomical Association (BAA) annual weekend in Winchester. At the BAA they call this talk the Alfred Curtis Memorial Lecture in memory of Alfred Curtis – a former BAA member who was instrumental in setting up the BAA annual weekend.

I’ll confess I didn’t know much about the BAA before this talk, and I came away extremely impressed at the level of knowledge and commitment about astronomy that I saw among its members. I was surprised to learn about how professional some of the observing facilities and programs of amateur astronomers are. Saturday night was very clear, so I was expecting the group would be anxious to head out for some star gazing, but actually many of them preferred to chat about the latest advances in astronomy at the bar with friends they don’t see too often, and leave their observing for nights they can really concentrate. They impressed me with information about their semi-automated observing of variable stars, or supernova which they then analyze on a computer, in much the same way that professional astronomers conduct observations

Many of the audience guessed in advance that I would be talking about Galaxy Zoo, despite my slightly cryptic title – “Finding Spirals – How to Look at a Million Galaxies”, and many of them told me afterwards about their involvement with Galaxy Zoo. We caught the end of the 100 hours of Astronomy drive (although after the 1 million classifications goal was met) so I advertised that in the talk, hoping to inspire some new Zooites.

The aim of my talk was to show all the interesting thing we can learn about galaxy formation and evolution from galaxy classifications. Rutherford famously said “All science is physics or stamp collecting”, my talk was in defense of the great physics you can do after you do some stamp collecting and sort out your album! I started by introducing the basic classifications of galaxies, and going back to the original 1926 paper by Edwin Hubble about galaxy classification. I then talked about the basic picture we have for galaxy formation and evolution in our expanding universe in light of the differences we observe between the two main classes of galaxies, such as spirals being mostly blue and solitary (or at least not in large clusters), and ellipticals being mostly red and in clusters or groups. I then talked about the digital revolution in astronomy and how we now have catalogues of millions of galaxies which astronomers cannot hope to visually classify themselves. Of course this is where I started talking about Galaxy Zoo with lots of stuff about how popular it is, and all the exciting discoveries that have so far come out of the first phase of Galaxy Zoo. I talked a little bit about my own work using Galaxy Zoo, looking at how the colours of the spirals vary with viewing angle. I finished by advertising Galaxy Zoo 2. I talked about some of the impressive statistics (like passing the 20 million clicks mark), and showed some of the examples of successful classifications. At the very end I showed a sneak peak of the Google Earth Tour of spiral galaxies which Ben Hoyle and myself made at Portsmouth. You can see this for yourself once you have classified at least 100 galaxies in Galaxy Zoo 2.

Karen.

Edit: a picture of BAA president, Roger Pickard and me deep in discussion about Galaxy Zoo.