Agnirva Space Premier League - Expedition #31300: Inside the Spherical Phantom: A Global View of Radiation on the ISS

When it comes to safeguarding astronauts from radiation, every shape and structure can yield valuable insights. The Matryoshka-R Spherical Phantom experiment onboard the ISS used a unique tool—a simple-looking but powerful spherical phantom—to gather data about the ever-changing radiation environment in space.

Led by V. Petrov of the Institute of Medical and Biological Problems of the Russian Academy of Sciences (IMBP RAS), this study explored radiation effects using a spherical object embedded with detectors. Unlike anthropomorphic phantoms, which mimic the human form, the spherical phantom offered a more uniform, isotropic shape, ideal for measuring radiation coming from all directions.

This design allowed researchers to gain a holistic view of radiation penetration and dose accumulation within a general volume. Placing the phantom in different compartments inside the ISS and even outside helped determine which locations offered more natural shielding. It also helped confirm how effective certain materials were at blocking cosmic rays and solar particles.

Why use a spherical shape? The answer lies in simplicity and symmetry. A sphere allows for more consistent data in all directions, making it easier to understand how radiation behaves in three-dimensional space. Each detector within the sphere recorded the type and amount of radiation over time, building a comprehensive dataset used to improve radiation models.

The Matryoshka-R Spherical Phantom experiment took place over numerous expeditions and played a key role in defining the radiation environment astronauts face. The data supports future spacecraft design, mission planning, and even astronaut training by offering a better understanding of which areas of a spacecraft are most at risk.

By blending innovative design with practical goals, this experiment demonstrates how simple tools can produce powerful results in the quest for safer space travel.

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