The Origin and Dynamics of High-redshift Disk Galaxies

It's been a long time since I went to an astronomy colloquium. Far too long.... and since I'm trying to get back in astronomy research mode (at least for the next month or so) I thought this would remind me what I love about optical astronomy and galaxy evolution. The colloquium speaker was Andreas Burkert from Ludwig Maximilians University, Munich, and he talked about why the redshift two Universe (high-redshift from my point of view, the Coma  Cluster is at z ~ 0.02) is one of the most interesting epochs of galaxy evolution.

This was a really excellent and quite amusing talk. Admittedly he lost me on some of the theoretical predictions, but the simulations and connection to the observations was really interesting. But it did also bing back frustrating memories and some of the reasons I used to be quite cynical about results. Image and spectral resolution is crucial in astronomy, and it's so refreshing to hear astronomer critique their own work and call things out for what they are. So many "discoveries" have been explained away because the observations hit instrumental limits (measuring velocity dispersion is classic example), or because the imaging/radio observations didn't have high enough resolution, or because other wavelength observations were not taken into account, or because models were too simple, or because the underlying assumptions are complete garbage. Astronomy research is a tricky thing to navigate, we'd never get anything done if we didn't start with some basic assumptions, theories and observations. At the same time, theories and observations don't progress unless someone is willing to challenge the status quo and deal with the hard stuff.

Having said that being too critical of the data and the data pipelines – to the point where it stops you from publishing – can be career suicide, particularly if you want to spend 100% (pr close to) of your time on pure research. I'll  be the first to admit that's been my failure over the years.

But I did love that this talk included lots of caveats (I thrive on the caveats even though many of them about the data) and an effort to change current theories. Not enough astronomers do this in talks. There is still far to much emphasis on finding new discoveries – many of which are disproven later on –  and getting papers out quickly before follow-up observations are taken.  To me the most interesting science papers and talks are the ones where astronomers really nail what's going on.

Plus Andreas showed us some pretty fantastic images of high-redshift (z~2) galaxies. The simulations were equally as spectacular.