The Pelorus Voyages fusion drive maintains a gentle 0.15g acceleration throughout each transit leg, which significantly reduces the severity of the zero-gravity adaptation challenges typical of older spaceflight. Passengers do not experience true microgravity during transit. However, 0.15g is still substantially lower than Earth's 1g or Mars's 0.38g, and the body's fluid distribution, vestibular system, and cardiovascular regulation respond to it. Most passengers experience a 24 to 72 hour adaptation period at the start of each new gravity environment, including at the first departure from Earth.

The most common early symptoms are mild head congestion and facial puffiness caused by fluid shifting toward the upper body, a subtle sense of "floating" even while seated, and occasional nausea in the first 12 to 24 hours. These are normal physiological responses and not signs of a medical problem. The vessel medical officer monitors all passengers during the first 72 hours and is available to assess anyone who develops more severe symptoms. Motion sickness medication is available from the medical bay without an appointment; most passengers who need it find that a single dose on the first evening is sufficient.

During the first 48 hours of each new transit leg, Pelorus Voyages restricts access to the outer observation deck and the EVA suit storage area. These restrictions exist not because the environment is dangerous but because the combination of reduced gravity and vestibular adjustment increases the risk of falls and disorientation in those areas. The main cabin, dining areas, and inner common spaces are accessible without restriction from departure.

Adapting back to higher gravity is also a process. Passengers on the Inner Planets Survey will experience three distinct gravity environments: 0.15g in transit, 0.38g on Mars, and 0.88g at The Aphrodite on Venus. The Venus arrival is frequently described as the most physically noticeable transition — after days at 0.38g on Mars, 0.88g feels heavy in the arms and legs. Pelorus Voyages provides a gravity re-adaptation orientation at Venus arrival that includes recommended stretching, hydration guidance, and a suggested first-day activity pace. The 24-hour period after Venus arrival is not the right time for the Titan fitness check; GST passengers should plan their Venus rest day accordingly.

Passengers with vestibular conditions or a history of motion sickness should declare this on their medical clearance form. The vessel carries a full range of antiemetic medications and can adjust cabin assignment to minimize vestibular triggers for affected passengers.
