We Don’t Know Why Astronauts Get Motion Sick

Space motion sickness (SMS) affects many astronauts, causing symptoms like nausea and dizziness. Despite long-standing awareness, the exact cause remains unclear. Three main hypotheses are explored: fluid shift, sensory conflict, and otolith asymmetry. Fluid shift suggests microgravity redistributes body fluids, affecting the vestibular system. Sensory conflict posits mismatched sensory signals cause SMS. Otolith asymmetry considers ear stone size differences. Ongoing research, including private space missions, aims to better understand and mitigate SMS.

What role do otoliths play in the vestibular system and how might they contribute to motion sickness?

What is the otolith asymmetry hypothesis and how does it relate to astronauts experiencing motion sickness?

What are some potential solutions or treatments for space motion sickness that astronauts might use?