Astronauts make concrete in space for the first time

European Space Agency astronaut Alexander Gerst works on the MICS experiment aboard the International Space Station.

(CNN)You could say things are getting a little more concrete on the International Space Station.

Astronauts on the station often share beautiful images and time lapses they capture from their unique vantage point 220 miles above the Earth. But they're also working on hundreds of experiments on the floating laboratory every day.
One recent experiment included mixing an aqueous solution with tricalcium silicate for the first time -- a scientific way of saying concrete. The basic ingredients for concrete include sand, gravel and rocks mixed with a cement powder and water-based paste. It sounds as easy as whipping up cake mix, but the actual process is much more difficult.
And the lack of gravity changes everything.
    Astronauts participated in the Microgravity Investigation of Cement Solidification project to understand how the chemistry of concrete is changed by zero gravity, down to the microscopic structures inside it.