Atlantic: As astronauts take spacewalks and then return to the spacecraft and remove their helmets, they have been reporting a peculiar smell—described variously as “seared steak,” “hot metal,” or “welding fumes.” To try to reproduce that odor, NASA has hired scent chemist Steve Pearce. Owner and manager of Omega Ingredients in the UK, Pearce was recruited after he reproduced the smell of the Mir space station for the art exhibition If There Ever Was in Sunderland. If Pearce succeeds, NASA could then use the aroma for training purposes to better acclimate astronauts to the space environment. What causes the odor? According to one researcher, it’s the “high-energy vibrations in particles brought back inside which mix with the air.” Pearce discusses the project in an online interview for the Discovery Channel.