What If the Sun Vanished for 24 Hours? Hour by Hour

If the Sun vanished right now, you would not notice for 8 minutes and 20 seconds. Then the sky at noon would turn black, the Moon would go dark within about 3 seconds, and Earth would start flying in a straight line at almost 30 km per second. This episode follows one full day without the Sun, hour by hour: what happens to the sky, the power grid, satellites, the temperature, animals and your own body clock, and what changes when the Sun comes back. We also look at what scientists say would happen if it never returned. 0:00 The Sun disappears 0:56 Minute 0 to 8: the last light 2:46 Minute 8 to hour 1: the sky goes dark 5:18 Hour 1 to 6: the world reacts 8:30 Hour 6 to 12: the cold begins 11:04 Hour 12 to 18: life in the dark 13:44 Hour 18 to 24: the edge 16:00 Hour 24: the Sun returns 17:46 What if it never came back? Sources: David Stevenson (Caltech) via Popular Science and Caltech "Question of the Month"; LIGO/Virgo GW170817 (speed of gravity); Ember Global Electricity Review 2025 (solar share of electricity); ENTSO-E and reports on the March 2015 European solar eclipse; Galen et al. 2018, Annals of the Entomological Society of America (bees during the 2017 eclipse); NASA (Sun, Earth and ISS facts). Orbit and light-delay figures marked as estimates are our own calculations. Stock footage: NASA Johnson Space Center, Earth Science and Remote Sensing Unit (ISS time-lapse videos, public domain). Photo credits (Wikimedia Commons; photos cropped and color graded): "Shavteli Street at Night, Tbilisi Georgia" (CC BY 2.0); Andrew Braun (CC BY 3.0); Oto Zapletal (CC BY 4.0); Brucewaters (CC BY 4.0); ESO/P. Horalek (CC BY 4.0); Harry Small (CC BY 3.0); Anja F (CC BY 3.0); DEDAL_Jaro (CC BY 2.0); Max Torben Heinrich (CC BY 3.0); Alexkom000 (CC BY 4.0); USFWS Mountain-Prairie (CC BY 2.0); ilovebutter (CC BY 2.0); Appie Verschoor (CC BY 3.0); diluvi.com, Anna i Adria (CC BY 2.0); ESO/Luis Calcada/Herbert Zodet (CC BY 4.0); NASA, ESA, J. Olmsted (STScI) (CC BY 4.0); Oregon Department of Transportation, Gary Muir (CC BY 2.0); Bering Land Bridge National Preserve (CC BY 2.0); Pcziko (CC BY 2.5); MARUM, University of Bremen (CC BY 4.0); Conall (CC BY 2.0). Other photos: NASA, NOAA, FEMA, NPS and public domain / CC0 contributors. Licenses: creativecommons.org/licenses AI disclosure: narration and some images are AI-assisted.