Pre-life molecules present in comets

The finding also substantially changes the understanding of chemistry in space.

The question of why molecular nitrogen hasn't been detected in comets and meteorites has puzzled scientists for years. Because comets are born in the cold, dark, outer reaches of the solar system they are believed to be the least chemically altered during the formation of the Sun and its planets.

Studies of comets are thought to provide a “fossil” record of the conditions that existed within the gas cloud that collapsed to form the solar system a little more than 4.6 billion years ago. In this cloud, since nitrogen was thought to be in molecular form, and it follows that comets should contain molecular nitrogen as well.

But the reason it isn't there is because it isn't present in the gas clouds whose microscopic solid particles eventually form comets, said Sébastien Maret, research fellow in astronomy at the University of Michigan, and Edwin Bergin, a professor of astronomy at the University of Michigan. Those clouds contain mostly atomic nitrogen, not molecular nitrogen, as previously thought.

Maret, Bergin, and collaborators from Harvard-Smithsonian Center for Astrophysics will publish their findings in the July 27 issue of the journal Nature.

The nitrogen bearing molecules in comets that crashed into Earth millions of years ago may have provided a sort of “pre-biotic jump start” to form the complex molecules that eventually led to life here, Bergin said.

“A lot of complex and simple biotic molecules have nitrogen and it's much easier to make complex molecules from atomic nitrogen,” Bergin said. “All DNA bases have atomic nitrogen in them, amino acids also have atomic nitrogen in them. By that statement what we're saying is if you have nitrogen in its simplest form, the atomic form, it's much more reactive and can more easily form complex prebiotic organics in space”. These complex organics were incorporated into comets and were provided to the Earth.

“What we're seeing in space is telling us something about how you make molecules that led to us,” Bergin said.

Also of importance is the fact that odd anomalies in isotopic values in meteorites can also be explained if the nitrogen is not molecular, Bergin said.

Media Contact

Laura Bailey EurekAlert!

All latest news from the category: Physics and Astronomy

This area deals with the fundamental laws and building blocks of nature and how they interact, the properties and the behavior of matter, and research into space and time and their structures.

innovations-report provides in-depth reports and articles on subjects such as astrophysics, laser technologies, nuclear, quantum, particle and solid-state physics, nanotechnologies, planetary research and findings (Mars, Venus) and developments related to the Hubble Telescope.

Back to home

Comments (0)

Write a comment

Newest articles

Lighting up the future

New multidisciplinary research from the University of St Andrews could lead to more efficient televisions, computer screens and lighting. Researchers at the Organic Semiconductor Centre in the School of Physics and…

Researchers crack sugarcane’s complex genetic code

Sweet success: Scientists created a highly accurate reference genome for one of the most important modern crops and found a rare example of how genes confer disease resistance in plants….

Evolution of the most powerful ocean current on Earth

The Antarctic Circumpolar Current plays an important part in global overturning circulation, the exchange of heat and CO2 between the ocean and atmosphere, and the stability of Antarctica’s ice sheets….

Partners & Sponsors