Quick Answer
About eight minutes after the Sun vanished, Earth would stop receiving sunlight and would also cease following its current orbit, moving approximately along the tangent to its old path. The surface would then cool rapidly compared with geological timescales, although the oceans and atmosphere would retain heat for much longer than the surface. Earth would eventually become a frozen, dark world with survival possible only in specialized environments.
The Sun is both Earth’s main energy source and the dominant gravitational body in the Solar System. Removing it creates two separate crises: loss of sunlight and loss of the gravitational field that keeps Earth in orbit.
The eight-minute delay
Light and changes in gravitational information propagate at the speed of light. Earth would therefore continue receiving sunlight for roughly eight minutes after the disappearance event. After that, daylight would end globally except for artificial and geothermal sources.
Earth leaves its orbit
Without the Sun’s gravity, Earth would no longer follow its curved orbit. It would travel approximately in a straight line tangent to its former orbit, while the Moon would continue interacting gravitationally with Earth.
The first days of darkness
Surface temperatures would begin falling, but the planet would not freeze instantly. Oceans, atmosphere and ground store thermal energy. Clouds and atmospheric circulation would also respond to the changing energy balance.
What happens to life?
Photosynthetic ecosystems would collapse first because their primary energy source disappeared. Food webs would then fail from the bottom up. Some organisms around hydrothermal vents and other chemically powered ecosystems could survive much longer.
Established scienceEarth receives nearly all of its surface energy from sunlight. Geothermal energy exists, but it is far too small to replace the Sun as the energy source for today’s biosphere.
The long-term world
Over very long timescales, the surface would become extremely cold and much of the atmosphere could eventually condense or freeze. Subsurface environments heated by Earth’s interior would become increasingly important refuges.
The bottom line
The disappearance of the Sun would first create an eight-minute delay, then darkness and orbital escape, followed by a slow transition toward a frozen planetary environment. It would be catastrophic for surface life, but not every form of life would necessarily disappear immediately.
A note on our approach: Every article on WhatIfLab separates what current science establishes from what remains genuinely speculative. Where we cite a figure or finding, it reflects published, mainstream research at the time of writing — not a prediction dressed up as fact.