The Indian Space Research Organisation on Wednesday said the training of astronauts for the ambitious manned mission 'Gaganyaan' will commence from the third week of January in Russia. Four astronauts have been identified for the mission, ISRO chief K Sivan said adding the training of astronauts will start from third week of this month in Russia. The work related to Chandrayaan-3 and Gaganyaan was goingon simultaneously, he said.