Watch: Expedition 48 takes off for its four-month long mission aboard the ISS

Three astronauts – NASA astronaut Kate Rubins, cosmonaut Anatoly Ivanishin of the Russian space agency Roscosmos, and astronaut Takuya Onishi of the Japan Aerospace Exploration Agency – left the Baikonur Cosmodrome in Kazakhstan on a new mission on Wednesday. The astronauts will test a range of upgraded systems on their spacecraft during their two-day journey to the International Space Station, where their mission will last for four months until October.

The crew is scheduled to arrive at the ISS early on Saturday morning. They will be part of Expedition 48-49. Expedition 48 began on June 18, the day members of Expedition 46-47 departed the space station. The arrival of the three astronauts is awaited by Commander Jeff Williams and Flight Engineers Oleg Skripochka and Alexey Ovchinin.

Here's footage of the Soyuz rocket being assembled.

Here are the astronauts talking about how they ready themselves for a trip like this and what they plan to do on board the space station.