Imagining what it would be like to visit another planet has been a staple of science fiction for decades. Whether here in the solar system or elsewhere in the universe, other worlds tend to intrigue us.
Still, it’s worth remembering that humans exist on Earth, not somewhere like Mars, for a reason – it’s the only place in the universe we know of that wouldn’t kill us horribly in minutes or less.
“Humans need oxygen to breathe,” said Jennifer Glass, associate professor in the School of Earth and Atmospheric Sciences & Biological Sciences at the Georgia Institute of Technology. Newsweek. “The Earth’s atmosphere today contains 20% oxygen. Without oxygen in the gas we breathe, humans die of asphyxiation – lack of oxygen – in about seven minutes.”
Without enough oxygen elsewhere in the solar system, death would come quickly. The only difference between planets is whether their temperatures or pressure would kill us faster.
Here’s what would happen on each planet, starting with the one closest to the sun.
The fact that Mercury is the planet closest to the sun already indicates that it would not be the most hospitable of planets. On the side of Mercury facing the sun, temperatures soar to 800 degrees Fahrenheit as the sun blasts its closest planet with full force. Meanwhile, on the night side, temperatures would drop to -290 F. This is because Mercury is, for all intents and purposes, a vacuum and has virtually no atmosphere to retain heat.
Therefore, death on the cold side would be similar to death in space and would likely be over within minutes. “If you died on the hot side, you would be burned to death within seconds, while asphyxiating and vaporizing all the water in your body,” Glass said.
Proportionally the most Earth-like planet in the solar system, but the similarities end there. Venus’ thick atmosphere gives it a greenhouse effect which sees its surface temperature soar to around 867 degrees F, according to NASA, and the thick atmosphere also means the pressure on the surface would be deadly. Needless, it also has clouds of sulfuric acid.
“While struggling to breathe, you would burn from the extreme heat and acid within seconds,” Glass said. “At least it would be a quick death, but it would be horrible.”
Mars probably has the toughest surface conditions in the entire solar system except Earth, with temperatures reaching a pleasant 70 degrees F in the summer, although they would dip to -225 degrees F at the poles.
However, even if a human were to be placed on the equator in summer, it would not last long. The atmosphere of Mars is made up of nearly pure carbon dioxide. In some ways, that would make it one of the worst planets to die on.
“If carbon dioxide builds up in our blood when a person asphyxiates, they experience the stressful sensation of shortness of breath before they pass out and die of asphyxiation,” Glass said. “If his blood is on the contrary diluted by breathing a gas without carbon dioxide, for example hydrogen, helium, nitrogen, methane, etc., the person will lose consciousness in a few seconds, without feeling shortness of breath, so death would be less painful, but they would still die within minutes from lack of oxygen.”
In short, death on Mars may be longer than elsewhere in the solar system, and potentially accompanied by extreme cold.
Jupiter, Saturn, Uranus and Neptune
The gas giants of the solar system are grouped together because the dying process would be basically the same, but also variable depending on where you go on the planet since they don’t have a surface.
Being placed in the center of a gas giant means instant death that would probably be too quick to live. Saturn’s core, for example, is estimated to be around 15,000 degrees F and the pressure at Jupiter’s core is so high it would be like having 160,000 cars stacked on top of each other all over your body.
In the clouds it may be a slightly different experience, but with the same inevitable ending. Temperatures range from -166 F on Jupiter to -330 F on Neptune.
“There’s no solid ground on the gas giants, so you’d just fall through them until you were crushed under their intense pressure,” Glass said, though you’d die long before you reached the top. core. “Their atmospheres are hydrogen with some helium, methane and water, but minimal carbon dioxide, so at least if you froze and were crushed to death, you’d pass out more gently, without the hypercapnia panic due to high carbon dioxide content, like on Venus and Mars.”
a few moons
As a bonus, humans would also die on every moon in the solar system. Betül Kaçar, professor and senior scientist at the NASA Center for Early Life and Evolution at the University of Wisconsin, Madison, said Newsweek that, in addition to not being able to breathe, people might experience being “bathed in radiation as you cross Jupiter’s magnetic field lines” over Europa, being “frozen instantly in a lake of methane and ethane” on Titan, or being “exploded into space in an icy geyser” on Enceladus.
Anyway, don’t forget your space suit.