This week we look at the light curve of the young variable star AA Ori. It is situated in the south of the Orion Nebula Cluster. It is your proto-typical young star that varies on all sorts of timescales up to about one magnitude. A detailed analysis is needed to decide if the main causes for the variations are changes of line of sight extinction or changes in the mass accretion rate. We show the data added after the data base was opened up again a few weeks back. There is also I-band photometry available for the star.

I would like to express my big thanks to the three newly recruited data processing helpers Kathy, Michel, and Cledison. Over the last few weeks they have made tremendous progress in reducing the backlog of images to be processed. Indeed, it has been reduced from about 4000 to now less than 400 images – new ones will surely be coming in ;-). About a thousand of these are shown in the light curve above. Their help does not just ensure we can analyse the data in detail, they also ensure the data are validated and checked, and we can hence trust the brightness measurements without having to spend effort on additional quality control. Thank you very much to all the participants processing images and observing the targets.

On the plus side, our observatory at the University of Kent is back in action after several month without a working mount – just in time for astronomical twilight to disappear……