Two teams report they have found the building blocks of life around a Sun-like star
The same week we learned that the human species may be older than was previously believed, it was disclosed that two teams of astronomers report that they have found molecules related to the building blocks of life at a Sun-like star, providing insight into the origins of life on Earth.
Using the Atacama Large Millimeter/submillimeter Array (ALMA) radio telescopes in northern Chile, the astronomers detected the presence of methyl isocyanate, a prebiotic complex organic molecule, in a star system called IRAS 16293-2422 that is 400 light years away from Earth. The ALMA was used in 2012 to detect a sugar molecule also found in earthly biology present in the same star system.
This chart shows the location of the Rho Ophiuchi star formation region in the constellation of Ophiuchus (The Serpent Bearer). The star Rho Ophiuchi, which gives the region its name, is marked with the Greek letter rho (ρ). The position of IRAS 16293-2422, a young binary star with similar mass to the Sun, is marked in red. Credit: ESO, IAU and Sky & Telescope.
"This star system seems to keep on giving. Following the discovery of sugars, we've now found methyl isocyanate. This family of organic molecules is involved in the synthesis of peptides and amino acids, which, in the form of proteins, are the biological basis for life as we know it," said Niels Ligterink and Audrey Coutens, who co-led one of the teams credited with the discovery.
The findings, which were presented in two papers that will appear together in an issue of the Monthly Notices of the Royal Astronomical Society, could contribute to one of science's greatest questions: How did life form? Scientists believe that, along with the rest of our solar system, Earth arose from material left over after the Sun was formed. But how living organisms came about is a matter for debate. As Wired points out, one theory holds that life came about on Earth independently from the Sun, after the planet was formed. The other states that the ingredients of life were were formed in a solar nebula and then arrived on Earth via comets. "The detection of this molecule points toward the latter theory," Rafael Martín-Doménech, one of the leaders of Centro de Astrobiología, told Wired.
The ALMA consists of 66 39-foot-tall telescopes and is the most expensive grounded telescope currently in operation. An international collaboration between North America, Europe and East Asia with Chile allows for round-the-clock use of the ALMA to study star and planet formation. The recent findings, which were made by astronomers from Spain, Italy, the Netherlands and the United Kingdom, mark some of the most significant enabled by ALMA.
Methyl isocyanate was discovered in IRAS 16293-2422 by detecting the light waves emitted by the protostar. This collection of light waves is like a fingerprint; each chemical has its own unique set, which allows astronomers the ability to determine the chemical makeup.