It's becoming a little crowded in space. There is now a record number of 19 people up in the heavens. The record was broken after the three-person crew on board a Russian Soyuz capsule docked at the International Space Station (ISS). On the recent mission were NASA astronaut Don Pettit and Russian cosmonauts Alexey Ovchinin and Ivan Vagner. They brought the number of residents on the ISS to 12. Chinese astronauts are also part of the record. They have three "taikonauts" working on the Tiangong Space Station. The remaining four space travellers are part of SpaceX's Polaris Dawn mission. That project saw a historic first ever civilian spacewalk last Thursday.

There is a point of contention regarding the recent record. That is over the definition of where outer space starts. NASA and the U.S. military regard the boundary separating Earth's atmosphere and outer space as being 80 km above sea level. With this interpretation, the record for humans in space is 20, set in May 2023 and tied in January of this year. However, the conventional definition of the edge of space is called the Karman Line. The International Aeronautical Federation puts this line at an altitude of 100 km above sea level. The new record uses this definition. The Karman Line is used for legal purposes to differentiate between what constitutes an aircraft and a spacecraft.