Did Life on Earth Begin on Mars? Sample 25, Viking, and the Evidence We Left Behind

Perseverance sealed the strongest potential Martian biosignature yet inside Sample 25. Viking's 1976 results are being re-litigated. NASA's return architecture lost funding as the evidence strengthened. This report reconstructs the science, the institutional bottleneck, the 2028 propulsion test, and the larger possibility that Mars sits upstream of Earth's biology.