CAPE CANAVERAL, Florida - The space station's two Russian astronauts stepped outside for the second time in less than a week Tuesday, taking a spacewalk that promised to be tame compared with last week's work with explosives.

Although Sergei Volkov and Oleg Kononenko had a lengthy to-do list, none of the chores were expected to be notably complicated or dangerous.

The job included installing a docking target to be used when a new Russian research module arrives next year, rearranging some foot restraints, and installing a new science experiment to the outside of the international space station.

They will also bring back inside an experiment that looked at cosmic effects on bacteria and fungi.

The Russian Space Agency originally planned just one spacewalk for Volkov and Kononenko.

However, another spacewalk was added and took priority to remove an explosive bolt from the Soyuz capsule parked at the space station; the unprecedented work was carried out successfully Thursday by the pair.

The explosives in the bolt had as much force as a big firecracker and could have blown off their hands.

The bolt was placed in a blast-proof cylinder and taken back into the space station. The two Russians will carry it with them when they fly back to Earth in the Soyuz in October.

Russian space officials want to avoid the steep, off-course descents that shook up the last two returning Soyuz crews. Engineers still don't know what went wrong, but suspect some of the explosive bolts may not have fired properly.

As he did last week, American astronaut Gregory Chamitoff retreated into the Soyuz for the entire spacewalk.

Space station officials wanted him in the capsule in case an emergency arose and the spacewalkers had to join him there.

Volkov and Kononenko have been living at the space station since April. Chamitoff arrived last month on space shuttle Discovery.