Despite Meri's disapproval, Sirius goes forward with his mission. As the sole passenger on his spacecraft, the Meriwell, Amory's only companion is a computer system known as the All Mother, which also operates inside his spacesuit.
Meri disapproves of Sirius's actions, but he goes ahead with his mission.  The only other person on board is the All Mother, a computer system that operates both in the spacecraft and within Amory's spacesuit.