Keen Software house announces a free weekend is underway for Space Engineers on Steam, celebrating the first anniversary of the release of the sandbox space game. Here's word on the weekend and the sale that's also now underway:

We are celebrating one year of Space Engineers with a Free Weekend on Steam! Starting from now, Space Engineers will be available to play for FREE until Sunday, October 12, at 1pm PST. We are also running a 40% discount off the regular price!*

If you didn’t have the chance to try the game until now, this is the best time to do or you can invite your friends to play.