The International Space Station (ISS) is a fully completed space laboratory, whose in-orbit assembly began in 1998 and officially ended on June 8, 2011 on the STS-135 mission.[1] ] The station is in a low orbit (between 340 km and 353 km), which allows it to be seen from Earth with the naked eye,[2] and travels at an average speed of 27,700 km/h, completing 15.77 orbits per day.