Gravestone on a Frozen Field Episode 4

When the Yamato lands on the Saturnian moon of Enceladus to collect some cosmonite and to answer a distress call, Susumu, accompanied by radar operator Yuki Mori and a medical team, investigates the remains of a crashed Earth ship, which he finds to be his brother's vessel, the Yukikaze. Unable to find any clue about Mamoru's whereabouts, they are ambushed by androids sent by the Gamilans and must fight them to escape.