This is what outer space smells like — and it’s stinkier than you’d expect

It turns out space helmets serve a dual purpose — to keep air in and stink out. Just like Earth, the universe emits various smells from every corner of the never ending universe, often of which are generally unpleasant, Space.com reported, citing numerous space expeditions over the decades. Although it is impossible to take a whiff of the cosmos without facing certain death, astronauts have long described strong odors clinging to their space suits after they return to their air locked chambers.

Those aboard the Apollo moon landings described the scent as gunpowder like, while others who traversed the International Space Station compared the smell to burnt steak. According to scientists, the source of the metallic, burnt meat stink can be attributed to Polycyclic aromatic hydrocarbons (PAHs), which are found in charred foods on Earth and routinely occur in outer space.

The metallic smell, however, is likely a reaction to oxygen rather than one that is found in space: single atoms of O2 cling to the astronauts’ space suit before they walk into the airless vacuum of space and repressurize upon reentry into the airlock, combining with fresh oxygen atoms to form ozone, or O3, Space.com reported.

Some astronauts who removed their helmets after a space walk have also reported that the ozone smells bitter and smoky and even like rum and raspberries — a description former NASA chemist Steve Pearce bottled into the perfume “Eau de Space” in 2020. The boozy odor is a bit more on the nose than the other descriptions and has previously been connected to Sagittarius B2, a vast dust cloud at the center of our galaxy that contains loads of alcohol, including vinyl alcohol, methanol and ethanol.

Luckily, the cloud also contains the chemical compound ethyl formate, which gives raspberries and rum their sweet fragrances. As if its name didn’t give it away, Uranus smells strongly of flatulence , a putrid discovery made in 2018. The seventh planet from the sun’s upper atmosphere is made up of hydrogen sulfide, the compound that creates the smell of rotten eggs and human farts.

Whether fortunately or not, the rugged conditions and extremely low temperature of the faraway planet would kill an Earthling long before the smell would. Although they are some of the prettiest parts of outer space, comets have landed a spot as one of the stinkiest. Similar to the planet Uranus, the balls of ice and dirt are surrounded by a halo of hydrogen sulfide molecules, as well as ammonia, which is reminiscent of the repulsive smell of urine, scientists discovered in 2014.

Oddly enough, they also give off a sweeter aroma of almonds. Scientists discovered that Saturn’s largest moon has the distinct smell of gasoline — which shouldn’t come as a surprise considering Titan is covered in rivers and lakes of oil. The moon’s atmosphere is also made of a dense smog of hydrocarbons, which are the molecules that form the crude oil that is used to make petrol.

The stench itself can be blamed on the molecule benzene, which is also found naturally in gasoline and floating throughout Titan’s atmosphere..