Abstract This model extends the Lava-Void Cosmology framework to planetary science and astrobiology. We propose that habitability is not merely a static spatial attribute (the "Goldilocks Zone") but a dynamic temporal fluid phase transition. The Mechanism: The Planetary Heartbeat By modeling planetary evolution as a viscous fluid system, we identify: Lava Phase (High Density): Eras of high geological viscosity where volatiles (water/CO2) are retained and life flourishes (e.g., Earth's Phanerozoic). Void Phase (Low Density): Eras where entropy exceeds viscosity, leading to atmospheric stripping and desiccation (e.g., Mars after 3.0 Ga). Breaker Horizons: Catastrophic resets (impacts/volcanism) that re-compress the system, allowing habitability to "bounce" rather than flatline. Solving the Fermi Paradox: The Great Filter The model introduces a multi-layered filter for intelligent life: Temporal Filter: Synchronization of "Lava Phases" across the galaxy. Spatial Filter: Evasion of "Cosmic Drains" (Black Holes). Adaptive Filter: The necessity of Nomadic architecture to survive Void Phases. Files Included: lava_void_planetary_science.pdf: Theoretical paper outlining the Habitability Index $H(t)$ and the Refined Drake Equation. lava_void_planetary_dashboard_ultra.html: Interactive simulation comparing Earth vs. Mars, visualizing the Great Filter Sieve, and modeling the Fermi Fluid galaxy. Lava-Void-Planetary-Dashboard.png: Visual reference of the habitability cycles and filter statistics. The complete mathematical derivation and extended discussion for Lava-Void Cosmology and all pillars can be found on https://www.mylivingai.com/