Awwal 13, 1432 H/Feb 16, 2011, SPA -- Two Russian cosmonauts began Wednesday a space walk outside the International Space Station (ISS) to carry out what officials described as complicated work to instal equipment. ISS crew members Dmitry Kondratyev and Oleg Skripotchka were to spend some six hours in work to install sensors to register earthquakes and lightning strikes on earth. Also, the two will be dismantling equipment from an experiment on the Russian module Svesda, officials at the space mission control centre outside Moscow said, dpa cited Interfax as reporting. Cameras installed in the cosmonauts' helmets will provide direct TV transmission as they carry out their work. It is the second space walk by Russian cosmonauts in less than a month. On January 21, in a 5-hour, 23-minute operation, they installed a camera to record docking manoeuvres of the Soyus capsule with the ISS. Besides the two cosmonauts, the current ISS crew includes Alexander Kaleri of Russia, US astronauts Scott Kelly and Catherine Coleman, and Paolo Nespoli of Italy.