ESA's (European Space Agency) Rosetta spacecraft discovered ingredients essential for the origin of life at the comet 67P/Churyumov-Gerasimenko. They include the amino acid glycine, which is commonly found in proteins.
The find is unique as it could help support the theory that these life-giving molecules first arrived on Earth courtesy of a crash-landing comet.
"This is the first unambiguous detection of glycine at a comet," Kathrin Altwegg, lead author of a paper on the molecules published Friday in Science Advances, said in a statement.
Glycine is the simplest of the amino acids — the molecules that come together to form proteins — and it's the only one known to form in the absence of liquid water.
Using highly sensitive equipment, Rosetta sniffed out glycine by its individual sweet smell, out of the dusty cloud around the comet. It's not the first time glycine has been found on a comet — that was in 2006, when scientists working on NASA's Stardust mission extracted the molecule from samples of Comet Wild-2 – but it's the first time it's been detected using instruments out in space.
Another crucial component detected by Rosetta is a phosphorus, a key element of DNA and cell membranes.
When combined with previous discoveries of oxygen, alcohol and sugar compounds on the comet, these finds make 67P/Churyumov-Gerasimenko look like the planetary equivalent of a box of cake mix: Just add water, heat and the right environment, and life can start to emerge, scientists say.
Like all comets, Churyumov-Gerasimenko is named after its discoverers. It was first observed in 1969, when several astronomers from Kyiv visited the Alma-Ata Astrophysical Institute in Kazakhstan to conduct a survey of comets.
Comet 67P is one of numerous short period comets which have orbital periods of less than 20 years and a low orbital inclination. Since their orbits are controlled by Jupiter's gravity, they are also called Jupiter Family comets. Churyumov–Gerasimenko was the destination of the European Space Agency's Rosetta mission, launched on 2 March 2004.