Three members of the Expedition 54 crew aboard the International Space Station (ISS), including NASA astronauts Mark Vande Hei and Joe Acaba, recently returned to Earth after months of performing research and spacewalks in low Earth orbit.

Mr Vande Hei, Mr Acaba and Alexander Misurkin (of the Russian space agency Roscosmos) landed southeast of the
remote town of Dzhezkazgan in Kazakhstan.

Their time on the ISS marked the beginning of the first long-term increase in crew size on the ‘US segment’, enabling NASA to double the time dedicated to research and achieve a record-setting week of research (exceeding 100hr); this included investigations into manufacturing fibre optic filaments in microgravity, improving the accuracy of an implantable glucoses biosensor, and measuring the Sun’s energy input to Earth.

The crew also ‘welcomed’ four cargo spacecraft delivering several tonnes of supplies and research experiments.

Orbital ATK’s Cygnus spacecraft arrived at the ISS in November, followed in December by SpaceX’s Dragon spacecraft. Two Russian ISS Progress cargo craft arrived in October and February.

Mr Vande Hei logged 168 days in space on this, his first mission. He ventured outside the space station on four spacewalks to perform essential maintenance work; Mr Acaba completed one spacewalk to lubricate an end effector and install new cameras (he now has accrued 306 days in space on three flights).

In February, Mr Misurkin undertook a spacewalk with fellow cosmonaut Anton Shkaplerov to replace an electronics box for a high-gain communications antenna on the Zvezda service module.

The spacewalk lasted 8hr 13min — the longest in Russia’s space programme history.

More information on the International Space Station can be found at the Web site (www.nasa.gov/station).