Macmillan’s science fiction imprint, Tor Books (@TorBooks), is launching a Twitter feed featuring a number of its marquee authors. The feed, #Torchat, will host hour-long discussions on the social networking site, about various SF topics, from 4-5 p.m. EST on the third Wednesday of every month. Tor authors currently lined up to host the chats include Greg Bear, Steven Gould, and M.J. Locke.

The first #Torchat, set for February 16, will be hosted by Bear, Gould, and Locke, and explore “hard” science fiction. As the publisher explained, the discussion will examine what “hard SF means, whose really doing it (and whose not...), and the science behind the fiction.” Tor publicist Justin Golenbeck (@jgolenbo) will moderate.