Space: 1999 S01 E21 Space Brain

"The Future Is Fantastic!"

An Eagle and its crew are crushed to death by an enormous energy field in space. When one of Alpha's astronauts is possessed by the anomaly, he tells them the energy field is a living space brain, which responded to the 'threat' with antibodies Finding the Moon on a collision course with the Brain, the Alphans make plans to avoid the same fate as the Eagle.