⬇️ What if Earth's gravity doubled?
You would weigh twice as much — and so would every building, tree and wave.
The science
Doubling surface gravity doubles weight (W = m·g). Walking would feel like carrying another you. Structures built for 1g would be dangerously overloaded; mountains could not grow as tall because rock strength limits height under gravity.
Immediate consequences (modelled)
Movement becomes exhausting; many buildings and bridges exceed design loads.
Possible long-term consequences (hypotheses)
Evolution would favour shorter, stronger bodies; the atmosphere would be compressed closer to the surface.
Assumptions: Doubling g by doubling mass (radius fixed) — density and escape velocity would also change.
Limitations: Does not model climate, geology, biology or engineering in full detail.
Reference: NASA / peer-reviewed planetary science