What Does the Universe Smell Like?

As we know, space is a vacuum devoid of air. Therefore, theoretically, you cannot smell anything in space. However, the presence of various types of molecules gives this vacuum some intriguing characteristics.

For a long time, astronauts have often mentioned a unique aroma that appears outside the vastness of space after their journeys.

They cannot smell it while flying because the design of their spacesuits makes them only perceive a scent similar to plastic. However, upon entering the space station and removing their helmets, they immediately notice a strong, distinctive odor that clings to their suits, helmets, gloves, and other equipment.

According to Lifehacker, astronauts from NASA have described space as having a smell reminiscent of “gunpowder, burnt steak, raspberries, and rum.” In 2020, this group of astronauts participated in creating a space-scented fragrance called Eau de Space.

“A quite pleasant ‘metallic’ sensation, akin to sweet-smelling welding smoke,” “the smell of burnt metal,” “the distinctive tang of ozone,” “walnuts and brake pads,” “gunpowder,” “burnt almond cookies” are some of the scents described by astronauts to the Australian Academy of Science (AAS) while moving in space.

Speaking to Live Science, NASA engineer and scientist Don Pettit described the smell of space as being quite metallic.

Space smells like “gunpowder, burnt steak, raspberries, and rum.” (Photo: NASA)

Additionally, Steven Pearce, a NASA chemist responsible for recreating the smell of space to help astronauts acclimate before their missions, noted that the metallic smell may also arise from the high-energy emissions of ions.

“I have never smelled anything like it before; it leaves a very memorable impression,” astronaut Kevin Ford of NASA remarked after his 2009 trip. “It’s hard to describe this scent. Amid the chaos, the most prominent smell I noticed was metallic. It reminded me of my summer days in college, laboring for hours with a welding torch repairing equipment. I never imagined that the smell of welding smoke back then would be similar to the smell of space,” Don Pettit, another astronaut, added.

Currently, there is no definitive conclusion regarding why astronauts can smell odors when flying into space. However, many researchers believe it relates to “chemical reactions that occur when the spacecraft re-pressurizes,” according to the AAS.

Specifically, experts speculate that the scent comes from oxygen atoms in the astronauts’ suits. When the spacecraft re-pressurizes, these atoms collide with oxygen molecules, transforming into ozone and producing an odor.

Besides this hypothesis, researchers believe that the collision of molecules in space with oxygen also contributes to the scent that astronauts detect.

“The scent in space resembles the product of high-energy vibrations in particles brought back (into the spacesuit), mixed with air,” a researcher shared with The Atlantic in 2012.

What do other places smell like?

Titan, Saturn’s moon, is rich in hydrocarbons and has a petroleum-like smell. (Photo: NASA/JPL).

We’re talking about planets. So what would the air smell like on these planets? According to Space, one of the places with the most recognizable atmospheric scent in our Solar System is Titan – Saturn’s largest moon.

Because this moon has a thick layer of hydrocarbon fog, nitrogen, methane, and benzene are formed in significant amounts. The combination of these gases produces a smell akin to oil, mixed with gasoline.

Meanwhile, Sagittarius B2 – a massive molecular cloud less than 400 light-years from the center of the Milky Way – has some intriguing scents. According to scientists, this region of space contains a lot of methanol and ethanol, so it likely has a smell similar to alcohol and spirits.

Moreover, the ethyl formate molecules present in the Sagittarius B2 cloud are also the chemicals responsible for the sweet aroma of raspberries and rum.