The second spacewalk in less than a week for International Space Station Commander Sergei Volkov and Flight Engineer Oleg Kononenko ended up well on Tuesday, at 7:02 p.m. EDT, after 5 hours and 54 minutes.

The two Russian astronauts resumed their work at the station’s exterior by continuing the installation of a docking target on the Zvezda service module, in anticipation for the Russian mini research module scheduled to launch next year.

After installing the docking target, the astronauts inspected the bolt holes where the antenna adapter will be placed during the docking (a Kurs antenna is yet to be installed; according to NASA, it will be used for the first time next year).

During the same spacewalk, they also installed an experiment that monitors seismic effects by using high-energy particle streams in the near-Earth environment, as well as straightened out a bend ham radio system antenna.

Their last task was to move the Biorisk experiment and free it from its mountings. The experiment was initially installed by Expedition 15 and is used for studying the effects of the space environment on microorganisms.

During the spacewalk, Flight Engineer Greg Chamitoff remained in the Soyuz capsule for emergency situations (in case the Pirs airlock could not be repressurized).

Another issue that concerns astronauts on the International Space Station is directly connected with the failure of the last two Soyuz capsules to have a safe landing on their journey back to Earth, as they both resulted in ballistic entries. According to NASA, one of the 10 explosive bolts that help separate the spacecraft from its propulsion module will be returned to Earth for closer examination.

The mystery surrounding the unlucky last two landings of the Soyuz capsules hasn’t been solved yet, but scientists and engineers believe it may be connected to a malfunction of one of the explosive bolts.