What could brake pads, burnt almonds, hot metal, and a seared steak have in common? According to the astronauts, the answer is that all of them they smell just like space does. And it is that, if the specific composition of space was already unknown to scientists, these testimonies from astronauts about the odors perceived during their stay in the International Space Station are much more so.
While some of these travelers define it as a pleasant smell, many others dismiss it as disgusting. What everyone agrees on is that it is a strong smell, hardly ignorable during the months of stay in space and that, on many occasions, reminds us of metallic or scorched odors: burnt meat, welding gases or oxidized metal.
The curious method of seduction of lemurs
space doesn’t smell
The strangest thing about this matter is that space does not smell, since there are no gases or air that can give off a characteristic aroma: there is only emptiness. So where do these unique smells come from? The scientific community proposes two possible hypotheses in response to this unknown.
One of the possibilities being considered is that the smell comes from a characteristic oxidation reaction during the depressurization process at the entrance of the ship. Unlike Earth, the oxygen found in the Universe is atomic, that is, it is a molecule made up of only one atom (O). However, inside the ship will exist the diatomic oxygen molecule (O2), necessary for respiration.
Therefore, scientists argue that this atomic oxygen could stick to astronauts’ suits and tools during space expeditions, and produce a ozone formation reaction (O3) upon contact with the diatomic inside the ship. That reaction would be the one that would originate that characteristic burning smell.
The two Spaniards who will become astronauts
Another hypothesis would establish the origin of smell in dying stars. During the final phase, the stars release a large amount of energy that produces a compound known as PAH (polyclinic aromatic hydrocarbon), which moves through space helping to create new stars, planets and comets. In addition, it is a compound that is also found on Earth, so its smell is recognizable and can be identifiable with that of the testimonies. Therefore, in this case, it would be the adhesion of these particles to the suits that would allow the astronauts to capture that smell when entering the ship.
The scent of shooting stars
“That mysterious aroma is the subject of brotherly debate among astronauts. It has been compared to grilled steak, hot metal, welding fumes, and the smell of barbecue, to name a few” These are the words of the astronautTim Peake collected in his book Why space smells like barbecue and other questions that only an astronaut can answer.
John McFall: the first physically disabled astronaut
In this work, among other topics, he narrates his complete experience with this aroma. Tim says that it was a pleasant smell for him, and in many cases it reminded him of the one that appears due to the static electricity when taking off a sweater or T-shirt too quickly or violently. At other times, the nostalgia of being away from home made him evoke a barbecue in summer: in his own words, “to sausages roasted on a charcoal grill”. Be that as it may, he rescues, above all, the romantic idea that this smell must be the one left by shooting stars due to their combustion.
eau de space: the fragrance of space
One of NASA’s interests was to be able to recreate that characteristic smell that experienced astronauts talked about in order to prepare future candidates. The objective was simple: to try to simulate the conditions of space during training to avoid unexpected surprises. This plan included the smell of space.
Thus, in 2008, they hired the services of Steve Pearce, an American chemist who founded the company “Omega Ingredients”, to try to identify the maximum possible substances that could radiate that characteristic odor and recreate the aroma. The project was a complete success and allowed NASA to have an imitation of the fragrance that the astronauts would encounter during the trip.
They reproduce the perfume that Cleopatra used
However, after a few years in secret, the decision was made to market the substance in the form of perfume under the name ‘Space Water‘. Although it may seem like a financial act, the ends were not economic. This market launch had the purpose of increasing interest in learning science, technology and mathematics through the experiential education.
Following the same purpose, for a couple of years, the fragrance “Eau de Luna” has also been on the market, at the same price as its companion. In this way, it seems that getting closer to the experience of traveling into space is a little more within everyone’s reach, although for the moment, it is only olfactory way.