On September 21, 2003, NASA’s Galileo spacecraft executed its final command: a deliberate, high-speed suicide dive into Jupiter’s crushing atmosphere. Launched fourteen years earlier, the probe had revolutionized planetary science, uncovering evidence of vast subsurface oceans beneath Europa’s cracked ice. Yet that discovery posed an existential engineering dilemma. Nearly out of thruster propellant, Galileo risked losing attitude control and crashing into Europa, potentially seeding an alien biosphere with resilient terrestrial microbes. In a technology landscape where systems frequently neglect end-of-life cleanup, Galileo's deliberate immolation established the gold standard for planetary protection. Mission controllers chose intentional vaporization while transmitting atmospheric data until the final microsecond, prioritizing environmental preservation over passive abandonment. It remains a poignant lesson for modern engineers: building enduring discovery frameworks demands planning an equally thoughtful exit strategy.