NEWS 7th April 2021: Unfortunately, this service has been suspended.
Over the past few months there have been millions of requests for the positions of Messier objects (particularly M31, M42, M45, M81, and M51 for whatever reason). This volume of requests has put unprecedented strain on my server using between 50-75% of the server resources (which is shared with others). As a result my web hosts have stopped this service. I cannot afford the resources that would be necessary to deal with the volume of requests that are currently being made (mostly needlessly).
I am sad to end this free service after 12 years but I genuinely don't have the resources to deal with abuse of this service.
Apologies if you had been using this service responsibly and relying on it.