When particles interact with each other they may become entangled,i.e, they may become connected even if they are separated by a large distance such that an action done on one affects the other.
China’s Micius Satellite which was solely dedicated to quantum information science was launched last year to transmit the entangled photon pairs.
Once the photons transmit to ground stations there was still connected despite travelling far and wide(1600-2400kms). The system used by the satellite has marvellous applications : it can be used for quantum key distribution which creates quantum quantum communication system which allows sharing of information between two parties which is impossible to intercept without alerting the users. Experts say that this system is on crack about even if in cryptic messages are sent over normal communication channels.
China’s scientists have set a new high creating a record for the longest quantum teleportation. In an experiment by the team led by Ji-Gang Ren at the University of science and technology in Shanghai , they fired laser beams carrying the entangled photons from the ground station to the satellite then entangling them with a third photon and measuring their quantum states (not revealing the states but checking if they were the same).
How does quantum teleportation work?
Quantum states are detectable but according to laws of quantum mechanics once you have observed a particle it changes which could be a great security measure, it has helped us transfer data to space which is a great feat. Particles just mimic each other over a distance when entangled Einstein called it ‘spooky action at a distance’.
For more information:
https://www.space.com/37506-quantum-teleportation-record-shattered.html
Through my eyes 