Kerbal Space Program has been around for a long time in one form or another. It was first playable in mid-2011, and spent two years on Steam Early Access before launching in 2015. It was clearly time well spent—you don't get a 96/100 review score for half-assing it—but despite the brilliantly strong launch, we really haven't heard much about it since.
Today, however, Squad delivered some pretty big news with the announcement of the first KSP expansion, Making History. It includes two distinct components: The Mission Builder, a set of "intuitive drag-and-drop" tools that will let players design and share their own missions, and the History Pack, a series of pre-made missions that will recreate historical, real-life missions into space.
The expansion will also add new parts to the game, including fuel tanks, adapters, decouplers, fairings, and command pods inspired by the American and Soviet space programs, and also Kerbal Personal Parachutes, which can save a Kerbal's life as long as they don't try to use it in the cold void of space. It will also bring scoring to the game, giving players a way to compare their performances at the end of missions.
Pricing and a release date will be announced later, but Squad confirmed in a separate post that it is standing by its April 2013 promise that all updates and expansions—including this one—will be free for people who bought the game prior to the end of that month.