The Nauvoo, the massive ship being constructed by Fred Johnson and his team, has the most powerful sensor and communication array ever built. Johnson used it to spy on what was happening during the Donnager battle.
Uncle Mateo removes a malfunctioning sensor wire in his helmet. He lifts his visor, exposing his face to the vacuum of space. He then exhales slowly to prevent embolism, then re-locks his visor and finally inhales.
Tig Fong (Kaipo) has made guest appearances on Syfy's Dark Matter, Lost Girl and Warehouse 13 and performed stunts in 12 Monkeys, Continuum, Alphas and Helix. He was also the stunt rigger on Poltergeist (2015), co-starring Jared Harris.
The story of the conflict between the Scipio Africanus and the Xinglong grew out of a single paragraph in the original book. The Belters starting to use rocks as weapons is exactly what Chrisjen is afraid of, as she mentioned on the roof of her house in Episode 4.