Forget shooting the moon; let's smell it. Astronauts have told us earthbound folks that space has a certain smell, and at the Denver Museum of Nature & Science you can experience it. At a hands-on, noses-on exhibit, you can sniff eight different interstellar fragrances, including the moon, Venus, and outer space itself.
The worst-smelling of these options has to be Comet 67P, visited by the Rosetta probe as it was releasing chemicals as the sun warmed up its icy outer layer. A long list of different ingredients (hydrogen sulfide, ammonia, hydrogen cyanide, carbon disulfide, formaldehyde, methanol and sulfur dioxide – you don't have to work for NASA to see some yucky things you recognize) yielded a mélange of rotten eggs, cat urine and bitter almonds.
The best smelling is a dust cloud called Sagittarius B2 made up of millions of gallons of alcohol (no, not the drinking kind). These alcohol derivatives are compounds such as ethyl formate. Happily, this makes the dust cloud smell like raspberries and rum. Even better: these organic compounds could have been the building blocks of amino acids: the key ingredient to life.
The science behind this is that all objects in space radiate light of a particular group of wavelengths. Seeing what's there and what's missing helps smart people like cosmonauts figure out which chemicals are in the object, in a process called spectroscopy. Spectroscopy can be performed even on faraway objects because their light reaches us on Earth (or sensors on our spacecrafts).
Two items in the exhibit that didn't require spectroscopy were the smell of the moon and of outer space, because astronauts themselves described them. Those who set foot on the moon to stir its dust reported an odor as of spent gunpowder. Hm.
As for outer space itself, its fragrance is said to resemble "burnt metal with faint traces of meat."