Spacewalking astronauts prepare for arrival of Russian lab in 2021

(Nasa via AP)

The International Space Station’s two Russian astronauts ventured out on a spacewalk to prepare for next year’s arrival of a long-delayed lab.

Commander Sergey Ryzhikov and Sergey Kud-Sverchkov — dubbed Sergey 1 and Sergey 2 by flight controllers — left four Americans and one Japanese inside.