Rosetta gets a whiff of Comet 67P, and it stinks of rotten eggs, pee and an assortment of other noxious fumes
Friday, October 24, 2014, 3:19 PM - Comets may be pretty to look at, and scientifically fascinating, but according to what the Rosetta spacecraft has detected wafting off of Comet 67P, they apparently really stink up the place.
The ESA's Rosetta spacecraft is a robotic mission, so there's noone on board to actually smell what the comet is 'dealing', of course. Also, even if there was someone along for the already 10+ year ride, taking their helmet off for a whiff wouldn't be a great idea anyway. However, ever since the spacecraft arrived at the comet, in early August, it has been watching the plumes rising from the surface with the mass spectrometers of its Rosetta Orbiter Sensor for Ion and Neutral Analysis (ROSINA) instrument.
Mixed in with the gases already detected coming off comet as of early September, like water, carbon dioxide, methane, ammonia and methanol, the instrument has picked up the spectral fingerprints of hydrogen sulphide, sulphur dioxide, carbon disulphide and formaldehyde. If you combined that all together into an 'Eau de Comet' from 67P, it wouldn't exactly be a best-selling fragrance.
As the Rosetta team wrote in their blog: "If you could smell the comet, you would probably wish that you hadn't."
"The perfume of 67P/C-G is quite strong, with the odour of rotten eggs (hydrogen sulphide), horse stable (ammonia), and the pungent, suffocating odour of formaldehyde," Kathrin Altwegg, principal investigator for the ROSINA instrument at the University of Bern, said in the blog post. "This is mixed with the faint, bitter, almond-like aroma of hydrogen cyanide. Add some whiff of alcohol (methanol) to this mixture, paired with the vinegar-like aroma of sulphur dioxide and a hint of the sweet aromatic scent of carbon disulphide, and you arrive at the 'perfume' of our comet."
It's a good thing the artists who created 'Metamorphosis', the art installation that was on display at NASA's Jet Propulsion Laboratory Open House in mid-October, hadn't known about this beforehand, or being this close to it would have been quite a different (and far less refreshing) experience.
'Metamorphosis', on display outside the JPL cafeteria, Oct 12, 2014. Photo by S. Sutherland
RELATED: Read about Comet Siding Spring's close encounter with Mars, and watch a special presentation at NASA's Jet Propulsion Lab about this and Rosetta's upcoming lander mission on Comet 67P/Churyumov-Gerasimenko
So, why bother 'sniffing' a comet?
According to the Rosetta blog:
"The key point, however, is that a detailed analysis of this mixture and how it varies as 67P/C-G grows more active will allow scientists to determine the comet’s composition. Further work will show how 67P/C-G compares with other comets, for example by revealing differences between comets originating from the Kuiper Belt (like 67P/C-G) and comets that hail from the distant Oort cloud (like Comet Siding Spring, which recently flew past Mars). The goal is to gain insights into the fundamental chemical make-up of the solar nebula from which our Solar System and, ultimately, life itself emerged."
The entire goal of the Rosetta mission is summed up in this fictional, but still spectacular video short, titled "Ambition."