Mailing lists for TOPCAT and friends

The following mailing lists are available for TOPCAT, STILTS and STIL:

Discussion list for users of the software. Users, potential users, developers and other interested parties are encouraged to use this to post questions, answers, bug reports, feature requests, comments, tips, experiences etc related to TOPCAT, STILTS or STIL. I sometimes also use this to float ideas and gather feedback about future directions of the software.

You don't need to subscribe in order to post messages here. If you post a message without subscribing, you will have to respond to an automatic confirmation email to prove you're not spam.

I will monitor the topcat-user list, and in most cases I would expect to post a reply to queries on the same day, unless another list user beats me to it. One reason for introducing this list is so that users can benefit from each others' experiences, and so that responses I make to queries can be seen by other readers (either at the time or in the list archive) who may be experiencing similar issues or thinking along similar lines. Another is so that I can gather opinions about future directions for the software from the user community.

I am still happy to respond to personal emails related to the software if you're more comfortable with that for any reason, but if the discussion might be illuminating to other users, consider mailing to the list rather than to me directly.

This list was rehosted at jiscmail in April 2015. It previously lived at That web page is not visible outside of Bristol University, so the archives are not visible before April 2015. For historical interest you can see a plain text archive (~1.5Mb) covering the period 03/2013-04/2015 here; email addresses have been munged to protect this innocent. If you send messages to the old list address, I'll bounce them back to you and ask you to resend them to the right one.

Low-volume read-only list for announcements of new releases and other news items. The web page is not visible outside of Bristol. All messages to topcat-announce are sent to topcat-user as well, so you only need to subscribe to this list if you want just the announcements.

This list was rehosted at jiscmail in June 2019; previously it lived at


You can subscribe/unsubscribe to either list from its web page (topcat-user or topcat-announce). Alternatively, send a message from your email address to with no Subject and the one-line body "SUBSCRIBE <list-name> <your-first-name> <your-last-name>" where <list-name> is either "topcat-user" or "topcat-announce"; as noted above, there's no point subscribing to both. To unsubscribe, send the message "UNSUBSCRIBE <list-name>". For more help, see

If you have trouble with subscriptions or list usage, contact me and I'll be happy to help.


Mark Taylor -- Astrophysics Group, School of Physics, Bristol University,