What if the Sun were to suddenly stop shining?

If the Sun suddenly "went out" (ceasing to emit light and heat, while assuming its mass remains for orbital stability), here's an expanded timeline of Earth's fate based on scientific principles:

• —8 Minutes Later: Sunlight takes about 8 minutes to reach Earth, so we'd notice the blackout then. The sky would go dark instantly during daytime, stars would become visible, and temperatures would start dropping as solar radiation halts. No immediate chaos beyond confusion, but satellite communications relying on solar power might begin failing.
• —First Hours to Days: Global temperatures drop rapidly—potentially 1-2°C per hour initially in exposed areas. Photosynthesis in plants stops immediately, dooming crops and algae that produce oxygen. Weather systems grind to a halt without solar-driven convection, leading to stagnant air and no new rain or wind patterns. Nights become perpetually freezing, and ecosystems start collapsing: insects and small animals die first from cold and lack of food.
• —First Weeks: Surface temps could fall to -20°C (-4°F) globally within a week, accelerating to -70°C (-94°F) or lower. Oceans begin freezing from the top down, but their massive heat reservoir might take weeks to months to fully ice over (starting with polar regions expanding). Most land plants wither and die, herbivores starve, and carnivores follow. Volcanic and geothermal areas might offer temporary warm spots, sustaining microbial life longer.
• —First Months to Year: Earth approaches deep-freeze levels, with averages below -100°C (-148°F). Liquid water vanishes as rivers, lakes, and eventually groundwater solidify. The atmosphere starts condensing: water vapor freezes out first, then carbon dioxide, and at extreme colds (around -183°C for oxygen and -196°C for nitrogen), gases liquefy and potentially solidify into a thin icy layer on the surface. Mass extinctions wipe out 99%+ of species; only deep-ocean hydrothermal vent organisms or subsurface microbes might persist in isolated, heated pockets.
• —Long-Term (Years Onward): The planet equilibrates near space's background temperature (~-270°C or 3K from cosmic microwave radiation). Earth becomes a rogue, frozen world—lifeless except possibly for extremophiles. If the Sun's mass vanished too, gravitational disruption could fling Earth out of the solar system, wandering interstellar space.

For humans: Survival odds are grim. We'd have hours to days before widespread panic and infrastructure failure (power grids, transport). Short-term refuge in insulated bunkers with nuclear/geothermal power, hydroponics, and oxygen recyclers could extend life for months or years for a tiny elite, but resource depletion (food, air, energy) would doom even those. No long-term viability without sunlight.

Let this put your existence in perspective.