The formation of planets and the origin of life are among the most intriguing questions for mankind. Our current understanding is that the crucial phase of planetary formation occurs within the so-called protoplanetary disks that are analogs of the birth site of our own Solar System. As a matter of fact, the chemical composition of these disks shape the properties of emerging planets along with their primitive atmospheres, as well as the composition of comets and asteroids. In the context of an Interstellar-Earth connection, and in particular the early Earth bombardment by the small bodies of the Solar System (comets and asteroids), it is noteworthy that prebiotic molecules, that might have made possible the appearance of life on Earth, were likely already present in the protoplanetary disk.

Using the Atacama Large Millimeter/submillimeter Array (ALMA; Chile), an international group of astronomers have reported the first detection of formic acid, HCOOH, towards the TW Hydrae protoplanetary disk located at only 190 light years from our Sun.

Formic acid, whose name derives from its abundant presence in terrestrial ants, is the simplest acid. “The latter contains a carboxylic group (-COOH), which stands as the basis for synthesis of more complex carboxylic and amino acids used by life on Earth”, said study lead author Dr. Cécile Favre. More specifically, this species is involved in a chemical route leading to glycine, the simplest amino acid, the basis of many proteins.

This finding demonstrates that a crucial ingredient for all living organisms on Earth is found in a protoplanetary disk analog to the solar nebula out of which our Solar System has been formed. Dr. Claudio Codella, a co-author of the study, concluded: “In other words, by studying objects similar to the Solar System progenitor, we can infer valuable information on when the blossoming of prebiotic species occurred.”

Notes:

This research was presented in a Letter entitled “First detection of the simplest organic acid in a protoplanetary disk” by Favre et al., to appear in Astrophysical Journal Letters.

The team is composed of: Cécile Favre (INAF-OAA, Italy), Davide Fedele (INAF-OAA, Italy), Dmitry Semenov (MPIA and LMU Munich, Germany), Sergey Parfenov (Ural Federal University, Russia), Claudio Codella (INAF-OAA, Italy), Cecilia Ceccarelli (IPAG, France), Edwin A. Bergin (University of Michigan, USA), Edwige Chapillon (IRAM and LAB, France), Leonardo Testi (ESO and Excellence Cluster Universe; and INAF-OAA, Italy), Franck Hersant (LAB, France), Bertrand Lefloch (IPAG, France), Francesco Fontani (INAF-OAA, Italy), Geoffrey A. Blake (Caltech, USA), L. Ilsedore Cleeves (CFA, USA), Chunhua Qi (CFA, USA), Kamber R. Schwarz (University of Michigan, USA) and Vianney Taquet (INAF-OAA, Italy).

The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of the European Organisation for Astronomical Research in the Southern Hemisphere (ESO), the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the National Science Council of Taiwan (NSC) and by NINS in cooperation with the Academia Sinica (AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI).

ALMA construction and operations are led by ESO on behalf of its Member States; by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America; and by the National Astronomical Observatory of Japan (NAOJ) on behalf of East Asia. The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.