Without a Spacesuit, How Would We Die? Experts Weigh In

Do you want to black out, swell, burn, or freeze? Those are your options if you ever decide to step out into space without a spacesuit. Even if you are on any of the other planets in our solar system, not having a spacesuit will spell death for you in up to a couple minutes, according to the experts.

If you're an avid watcher of any of the science fiction classics (Doctor Who, Star Trek, Firefly, and even Star Wars) you've likely found yourself wondering "could that really happen? Wouldn't their head explode?" when you see a character drift through space for even a fraction of a minute.

Even recent blockbuster Guardians of the Galaxy shows a scene where Chris Pratt quickly becomes a near-popsicle (I won't say how or what happens next) in the endless expanse.

Unsurprisingly, this is a question that experts have been very frequently asked, and they have done a pretty good job trying to settle every curiosity.

One of the first times this was officially answered was probably back in 1997, when the Goddard Space Center's "Ask an Astrophyisicist" attempted to answer a 30-year-old question concerning the movie 2001: a Space Odyssey.

In the classic film, the protagonist, Dave, shot out of an airlock without a helmet.

"Should he have 'blown up' or is there 'no difference' as shown in the movie?" one citizen asked.

According to NASA, Dave likely would not have been awake to find out.

"We had a test subject accidentally exposed to a near vacuum (less than 1 psi) in an incident involving a leaking space suit in a vacuum chamber back in '65," the agency reported. "He remained conscious for about 14 seconds, which is about the time it takes for oxygen-deprived blood to go from the lungs to the brain. The suit probably did not reach a hard vacuum, and we began repressurizing the chamber within 15 seconds."

Thankfully, the unnamed "test subject" regained consciousness quickly afterwards, and showed no sign of injury after a thorough examination.

NASA's Henry Spencer reviewed a number of studies on chimpanzees for a more thorough answer to the "Ask and Astrophysicist" question.

"You do not explode. Your blood does not boil. You do not freeze. You do not instantly lose consciousness," he writes.

"If you don't try to hold your breath, exposure to space for half a minute or so is unlikely to produce permanent injury," he explained, adding that problems like sunburn, swelling, and "the bends" - a decompression sickness - can become a problem after 10 seconds or so.

Earlier this year, the Smithsonian's Eric Schulze added to this, explaining that "with no outside pressure, air expands. It can rupture the tissues in your lungs. Meanwhile, the water in your body turns into vapor beneath your skin, causing the mother of all bloating."

Schulze says that a spacesuitless person will likely swell to about twice their normal size, but he or she won't explode. Human skin is just strong enough to hold in that mounting pressure.

Space has other hazards that spacesuits are designed to protect humans from. Lethally cold temperatures and radiation are two slower killers that can affect a person in space, but realistically, no one would survive long enough to worry about those.

In a thinly veiled promotion for Neil deGrasse Tyson's new podcast Star Talk Radio, Business Insider recently took the "no spacesuit" question a step forward, asking Tyson to forget about space, and to explain what would happen if someone was caught on any extraterrestrial planet in just street clothes.

The famous astrophysicist starts with Mercury, the closest planet to the Sun, with one side very hot and the other very cold.

"If you straddled that zone [between the two extremes] like a rotisserie chicken... you would survive as long as you could hold your breath," he explained.

That's about two minutes for the average person. Granted you would not be very comfortable for that brief time on Mercury.

With Venus, a planet that averages about 900 degrees Fahrenheit, Tyson is quick to point out that it surprisingly has about the same gravity as Earth.

"You you would be very familiar walking around, until you vaporize."

When it comes to the gaseous planets of our solar system (Jupiter, Saturn, Uranus and Neptune), Tyson says "forget about it." If poisonous fumes don't kill you first, the intense gravity of these planets will quickly pull a person to their center, where he or she will be crushed into nothing in less than a second.

But what about Mars? Chris Webster from NASA's Jet Propulsion Laboratory chatted with Business Insider's Dina Spector via email to address this question.

"Any humans on Mars would have to contend with the lack of oxygen - only about 0.1 percent compared to Earth's 20 percent - the very cold surface temperatures, the ubiquitous and irritating dust, the intense UV radiation, surface chemicals and oxidants," Webster said. "And all this before they started looking for food and water!"

He adds that an unprotected human would have trouble lasting more than a few minutes anyways as the Red Planet's atmosphere is amazingly thin.

Even with an oxygen mask, you would have a hard time breathing out because of the pressure gradient between your lungs and the Martian atmosphere outside your chest.

And remember that "boiling" we talked about earlier? While in the vacuum of space this may not happen, on Mars it's a shocking reality.

"The pressure is so low that liquid water is not stable," NASA's Jennifer Heldman explained in an Ames Research Center Q&A. "It is below what we call the 'triple point' and so it will boil, even at the low temperatures on Mars."

And while water and even blood boils at Martian Noon (which averages about 70 degrees Fahrenheit) it can instafreeze at night at 76 degrees Fahrenheit below zero.

The lesson? When you book your next ticket into outer-space, don't try to imitate your favorite captain, Vulcan, Time Lord, or even Star Lord. Just remember to bring a spacesuit.