Space: the final frontier. At this point it feels inevitable that humans will end up living and travelling in space somehow. One day it might be entirely unremarkable for humans to die in space - but as of 2020 only three people have passed away outside the limits of planet Earth.
While the history of space travel is sadly marred with tragic and oftentimes horrific fatal accidents, most have occurred either on take off or after re-entry. Most deaths have occurred well below the Kármán line, which at 100km above sea level marks the official start of 'outer space'.
Sadly for everyone who hates movies where the dog dies (i.e., everyone), the first death of an Earth-based life form in space was actually Laika, the Russian canine cosmonaut. At the time when Laika was launched into space, the technology to bring her back to Earth had not yet been developed, so it was always doomed to be a one way flight.
However Laika sadly died even earlier than expected - while official Soviet reports stated that she survived until her oxygen ran out on day six of her flight, it was revealed in 2002 that she actually died of overheating within a few hours.
The first and only human fatalities above the Kármán line were also part of the Soviet space program, albeit more willing participants than poor Laika.
The crew of the Soyuz 11 mission of 1971 consisted of three cosmonauts: Commander Georgy Dobrovolsky, Flight Engineer Vladislav Volkov and Test Engineer Viktor Patsayev. The mission was the second to Salyut 1, the world's first space station, and the first to dock successfully after the Soyuz 10 failed to properly dock.
The mission encountered problems from the start, docking with Salyut 1 only to encounter a burnt, smoky atmosphere on the space station. Their first day consisted of fixing the station's ventilation before retreating to the Soyuz to allow the air to clear.
Other slightly alarming details included the fact that using the station's on-board exercise treadmill as they were required to do twice a day caused the entire station to vibrate. An electrical fire aboard the station during the mission also contributed to its length being cut short.
When it came time to return to Earth, the mission was considered a success, setting new spaceflight duration records after spending 22 days in space. This record would not be broken for almost another two years. The three cosmonauts were Soviet heroes, the world-first mission seen as a triumphant response to the US putting a man on the moon. The atmosphere on the day of Soyuz 11's scheduled landing was one of celebration.
From the ground, the Soyuz's re-entry was thought to have occurred normally. The entire process was automated, from the parachute opening to the rockets firing for a soft landing. All was thought to be perfect - until the ground crew opened up the capsule to discover the crew of three dead.
Kerim Kerimov, chair of the State Commission offered a horrifying description of what they found in that capsule:
"Outwardly, there was no damage whatsoever. They knocked on the side, but there was no response from within. On opening the hatch, they found all three men in their couches, motionless, with dark-blue patches on their faces and trails of blood from their noses and ears. They removed them from the descent module. Dobrovolski was still warm. The doctors gave artificial respiration. Based on their reports, the cause of death was suffocation."
The warmth of Dobrovolski's body spurred rescuers to continued attempts to revive the men, but at this point they didn't know what the crew had suffered to leave them in this state.
Later investigations determined that a catastrophic failure had occurred upon re-entry, with a faulty separation of two spacecraft modules causing a valve to blow open, rapidly depressurising the craft at an altitude of 168km. The incident would have been fatal within seconds, with the cosmonauts exposed to the vacuum of space for up to 11 minutes.
Official autopsies concluded that the cause of death was hemorrhaging of blood vessels in the brain caused by exposure to the vacuum, which made the oxygen and nitrogen in their bloodstreams bubble and rupture vessels. However these results were not announced publicly for a number of years.
The tragic deaths of the Soyuz 11 crew led to all Soviet spaceflight being put on hold as the Soyuz spacecraft was redesigned to allow occupants to wear pressure suits during re-entry, adding an extra level of safety to prevent a repeat of the disaster. Since being redesigned, the Soyuz is still in use today, ferrying crew members to and from the ISS.
This article has been updated since its original publication.