A team of astronomers have revealed that interstellar space is impregnated with a fine mist made up of molecules that resemble grease. The recent study estimates the quantity of “space grease” in the Milky Way: 10 billions of billions of billions of billions of tons – enough for 40 trillions of billions of billions of blocks of butter.
Organic matter contains carbon, a material considered essential to life. Until now, there has been real uncertainty regarding its abundance in space, with about half of it expected to be found in the stars in its pure form. The rest is chemically bound in two main compounds: aliphatic carbon and a gas based carbon, naphthalene. A team of astronomers recently analysed analogue interstellar dust in the laboratory and used their results to estimate the amount of aliphatic carbon (similar to grease) found in our galaxy.
“The combination of our laboratory results with observations from astronomy observatories now allows us to measure the quantity of aliphatic carbon between us and the stars”, explains Professor Tim Schmidt, from the University of New South Wales (Australia) and co-author of the study. There may be around 100 greasy carbon atoms for every million hydrogen atoms, which represents between a quarter and a half of available carbon. “In the Milky Way, this represents around 10 billions of billions of billions of tons of greasy matter, enough for 40 trillions of billions of billions of blocks of buttter”.
The windscreen of a future space craft travelling though interstellar space could thus find itself covered in a sticky layer. “Among other things, there would be interstellar dust, made up of partially grease, soot and siliceous dust like sand”, he continues, adding that the “grease” is swept into our own solar system by solar winds.
These discoveries bring scientists even closer to calculating the total quantity of carbon – which is essential to life – in interstellar space, which allows for the formation of stars and planets. The team are now planning to look in more detail at naphthalene, which will involve further laboratory experiments.