Engineers have developed a compact, battery-powered radio probe called the Gravity Imaging Radio Observer (GIRO) that aims to reveal the secrets of alien planets by using gravity fields to map their interiors and compositions.

GIRO reflects radio signals sent from the host spacecraft, measuring variations in gravitational fields of planets, moons, and asteroids. By analyzing these variations, researchers can determine the internal structure and dynamics of celestial bodies, answering questions about their mass, density, composition, and more.

High-accuracy gravity data is crucial for understanding faint gravitational signals, exploring risky environments, and situations with limited data acquisition opportunities. GIRO's high precision, low cost, and ability to carry multiple probes make it a valuable tool for future space exploration missions.

Compared to ground-based tracking, GIRO is expected to provide 10 to 100 times better accuracy, allowing for detailed mapping of gravity fields and revealing subtle features of a planet or moon's interior structure.

By matching past mission capabilities like GRAIL, GIRO can cut costs and complexity while delivering accurate gravity measurements. This means gravity science can be integrated into broader exploration missions without the need for dedicated spacecraft.

GIRO may open doors to exploring smaller celestial bodies and remote planetary systems, advancing our understanding of planet formation, evolution, and the potential for life.

Challenges in designing GIRO experiments include careful mission planning to ensure accurate data collection, battery life considerations for outer-planet missions, and compliance with planetary protection rules.

Despite these challenges, GIRO could be integrated into a planetary mission within one to three years, pending budgetary and political constraints. Building and testing flight-like prototypes in simulated mission conditions are crucial milestones before GIRO can be incorporated into upcoming missions targeting asteroids, moons, or outer planets.