What is the record distance for quantum entanglement?

The answer

In 2017, China's Micius satellite established quantum entanglement between two ground stations separated by 1,203 kilometers, setting the distance record. By 2023, Chinese researchers extended satellite-based quantum key distribution to span 4,600 kilometers between ground stations using trusted relay nodes. The entangled photon pairs maintain instantaneous correlations regardless of distance, a phenomenon Einstein called 'spooky action at a distance.' The 2022 Nobel Prize in Physics was awarded to Alain Aspect, John Clauser, and Anton Zeilinger for their entanglement experiments proving Bell inequality violations. These advances are foundational for building a global quantum internet and unhackable communications networks.