Washington: Three crew members from US, Russia and Japan - including a NASA biologist - were on their way to the International Space Station (ISS) after a successful launch from the Baikonur Cosmodrome in Kazakhstan on Thursday. Kate Rubins of NASA, Soyuz Commander Anatoly Ivanishin of the Russian space agency Roscosmos and Takuya Onishi of the Japan Aerospace Exploration Agency were travelling in an upgraded Soyuz spacecraft. They will spend two days -- and 34 Earth orbits - testing modified systems before docking to the space station's Rassvet module on Saturday. The arrival of Rubins, Ivanishin and Onishi returns the station's crew complement to six. They will join Expedition 48 Commander Jeff Williams of NASA and Flight Engineers Oleg Skripochka and Alexey Ovchinin of Roscosmos. The Expedition 48 crew members will spend four months conducting more than 250 science investigations in fields such as biology, Earth science, human research, physical sciences and technology development. Rubins holds a bachelor's degree in molecular biology and a doctorate in cancer biology. Ivanishin and Onishi are scheduled to remain aboard the station until late October. Williams, Skripochka and Ovchinin will return to Earth in September. Expedition 48 crew members are expected to receive and install the station's first international docking adapter which will accommodate future arrivals of US commercial crew spacecraft. Scheduled for delivery on SpaceX's ninth commercial resupply mission (CRS-9) to the station, the new docking port features built-in systems for automated docking and uniform measurements. Investigations arriving on SpaceX CRS-9 this month will test capabilities for sequencing DNA in space, regulating temperatures aboard spacecraft, understanding bone loss and tracking ships around the world. Other investigations will study how to protect computers from radiation in space and test an efficient, three-dimensional solar cell.