Comets: Cradle of Creation or Nature without Life?

This seminar is part of the EAI on-line seminars

By Jan Hendrik Bredehöft, Institute for Applied and Physical Chemistry, University of Bremen, Germany

13 June 2023, 16:00 CEST

For a long time, it was assumed that the organic chemical materials necessary for the building of the first living system must have been imported to Earth from space. This was mostly due to the fact that the time between the end of the late heavy bombardment phase of Earth’s development and the age of the first fossils seemed to be too short to allow for the long and arduous process of chemical evolution that would culminate in the first “living thing” and then for biological evolution to take over and evolve into the organisms that actually left fossils.

The study of meteorites showed that they are indeed full of the organic compounds that life also utilizes. These chemicals are formed on meteorite parent bodies by aqueous alteration of simpler more primordial material. This primordial material in turn is what today can still be found in comets. Their study, both in the lab and in situ, provides a window into the very deep chemical past of our solar system.

In recent years, new and much improved models for the origin of the organic feedstock for the origins of life on Earth as well as a much better understanding of Earth’s earliest history have come about. Delivery of organics from space to explain the origin of life seems longer necessary. I will discuss whether comets truly are the “Cradle of Creation” or whether they represent Nature without Life.