The Tragic Misadventure: Death in Space

The process of an astronaut dying in space can play out in several different scenarios with varying internal and external factors taking hold of the human corpse from time to time.

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By Cadence Li

In science fiction movies, there tends to be a recurring climax scene where a character gets thrown into the cold vacuum of space, never to be seen again. While such extreme situations are uncommon in real life, the phenomenon of an astronaut “dying in space” is not unheard of during intergalactic expeditions.

Since humans first stepped into the field of space exploration more than six decades ago, we have lost a total of 18 people in space missions, 14 of whom were NASA astronauts. Though this number may appear to be relatively low considering the 550 people who have ventured into space, more will likely become subject to space flight deaths as exploration projects become more advanced in the upcoming decades. Many launchings of a space mission with a human crew will inevitably encounter unexpected errors—often negligible, but sometimes devastating with no turning back—that may result in detrimental consequences and misadventure.

A spacewalk, or activity completed by an astronaut outside a spacecraft, is perhaps one of the coolest and most popular scenes in movies, appearing in everyone’s adventurous childhood dreams. As astronauts wander in our vast universe, however, they are exposed to many dangers. Tiny meteorites, for example, can slice through and puncture a hole in their protective suits, which serve to create a pressurized and oxygenated environment while shielding them from ultraviolet radiation and extreme temperatures in the external space surroundings. In less than 10 seconds, a process called ebullism takes place as all the fluids inside their bodies, including water and blood, vaporize. The dissolved nitrogen then near their skins begins to form bubbles, reaching nearly twice the size of a balloon as a result of the extreme reduction in the surrounding pressure. Despite the unavailability of oxygen in space, the astronauts’ circulatory systems continue to deliver oxygen-deprived blood to different parts of the body. However, after 15 seconds, they lose complete consciousness as their brains shift to a “shutdown mode” to conserve energy. Within 30 seconds, their internal organs, particularly the lungs, stop functioning and their entire bodies become paralyzed, and within a few minutes, they die from suffocation

There is a common misconception that dead human bodies in space decompose the same way as those on Earth. Decomposition on Earth begins several minutes after death through autolysis, or self-digestion, where hydrolytic enzymes from the lysosome begin to break down all the cellular components as the plasma membrane gets breached. Damaged blood cells then spill out of broken vessels, settling the blood in capillaries and small veins while discoloring the skin.

In space, however, several scenarios can take place after the death of an astronaut. In the first, death and decomposition occur on a corpse without a protective spacesuit. In such instances, the body would freeze rapidly, halting any biological processes. This frozen corpse would then drift into the vast expanse of the cosmos for thousands, and sometimes even millions of years, before encountering another object or force that would act on it. If the frozen corpse was near a celestial body, such as a nearby star or black hole, unfiltered space radiation, which is comprised of extremely high-energy subatomic particles of mostly protons and atomic nuclei with electromagnetic emissions, would rip through the body like a firestorm and eventually cause mummification.

Things play out quite differently if the dead body is in a spacesuit. Because the suit contains all the exhaled air from the astronaut with the presence of sufficient heat, the decomposition process would actually be similar to that on Earth, though the bacteria would only carry out the process for as long as the oxygen lasts. Beyond this point, decomposition would be taken over by anaerobic processes such as fermentation. As of now, there is no confirmed settlement plan or official policy for dealing with corpses in space, as NASA’s solutions to unexpected solutions are often discussed in real-time between the Flight Operations Directorate, Human Health and Performance Directorate, NASA leadership, as well as their International Partners.

Let’s consider an astronaut dying inside the spacecraft. In this case, the simple solution may be to dump the corpse out of the vehicle and let it sail through the cosmos freely. However, an agreement called the “space debris mitigation guidelines” signed by the United Nations has banned these sets of “littering” actions as the corpses can potentially collide with another spacecraft and turn into a flight hazard or land on an alien planet. In an attempt to tackle this long-speculated problem, there have been new proposals that discuss some of the more probable solutions for handling corpses in space. The green burial company Promessa, for example, collaborated with NASA and came up with the GoreTex bag, or a “Body Back,” in which the human corpse, dressed in NASA’s indoor spacesuit, is placed inside an airtight sleeping bag and then exposed to the freezing temperatures of outer space for an hour until it becomes brittle. A robotic arm, known as a “robonaut” then vibrates the cloth coffin intensely for 15 minutes as water slowly evaporates from the remains through a vent in the bag. The shattered frozen corpse then turns into about 50 pounds of human body dust that could then be stored outside the spacecraft until re-entry into the Earth’s atmosphere, where the remains are returned to the deceased’s family.

Such tragic phenomena of space flight fatalities can be prevented from occurring in prospective missions through the reinforcement and improvement of precautionary measures and research taken before the launching of every space flight. With the expansion of space exploration comes the increased potential for misadventure. Hence, it is crucial to gain a deeper understanding of the complexity of nature and ourselves through such strange yet relevant aspects of space travel before technological innovations edge us even closer to a life outside of the atmosphere.