While observing Comet Lovejoy from the Paris Observatory, astronomers watched the comet as it was releasing large amounts of ethyl alcohol and a type of sugar out into space. The discovery marks the first time that the same alcohol found in alcoholic beverages has been observed in a comet, adding to the evidence that comets could have provided the complex organic molecules necessary for life to gain a foothold on Earth.
In a paper published on Oct. 23 in the journal Science Advances, lead author Nicolas Biver remarked that during its peak activity, Comet Lovejoy was releasing the equivalent of at least 500 bottles of wine every second. Along with the alcohol, the team discovered 21 other organic molecules in the comet gas, including a simple sugar known as glycolaldehyde.
These observations were made when the comet was passing closest to the sun, which was around the end of Jan. 2015. Using a 30-meter radio telescope located in the mountains of Spain, the team observed the comet glowing in the microwave spectrum. Each type of molecule glows at a unique and specific frequency in the spectrum, allowing the team to identify each molecule from the signature it was emitting towards the telescope. With advanced technology, the team was able to analyze a wide range of microwave frequencies simultaneously, which led to the discovery of several types of molecules spewing in different amounts within a short observation period.
There are a number of scientists who think comets delivered the supply of the necessary molecules for life when they impacted the Earth. The recent discovery in Comet Lovejoy and in other comets serves to support their hypothesis. The findings support the idea that comets carry very complex chemistry. “We’re finding molecules with multiple carbon atoms. So now you can see where sugars start forming, as well as more complex organics such as amino acids,” said Stefanie Milam of the NASA Goddard Space Flight Center, co-author of the paper on the findings. Similarly, in July, the European Space Agency reported that its Philae lander from the Rosetta mission, currently in orbit around a comet, detected sixteen organic compounds as it descended toward and bounced around the comet’s surface. The agency reports that some of the detected compounds play key roles in the creation of amino acids and nucleobases, the building blocks of DNA.
The next step is to determine whether these complex molecules were part of the primordial dust cloud that birthed the solar system or part of the protoplanetary disk that orbited the young sun billions of years ago.
Comets are thought to preserve the material from these clouds, created when dust grains clump together and grow to form large rocks. These rocks are thought to have been part of the Late Heavy Bombardment 3.8 billion years ago when comets and asteroids were impacting the young Earth in large numbers. Such comets like those being observed now could have been the ones that delivered the ingredients necessary for the emergence of complex life on Earth.