New molecule found in space connotes life origins
New molecule found in space connotes
life origins
Posted by:
Tarun Kumar
Hunting from
a distance of 27,000 light years, astronomers have discovered an unusual
carbon-based molecule -- one with a branched structure -- contained within a
giant gas cloud in interstellar space. Like finding a molecular needle in a
cosmic haystack, astronomers have detected radio waves emitted by isopropyl
cyanide. The discovery suggests that the complex molecules needed for life may
have their origins in interstellar space.
Using the
Atacama Large Millimeter/submillimeter Array, known as the ALMA Observatory, a
group of radio telescopes funded partially through the National Science
Foundation, researchers studied the gaseous star-forming region Sagittarius B2.
Astronomers
from Cornell, the Max Planck Institute for Radio Astronomy and the University
of Cologne (Germany) describe their discovery in the journal Science (Sept.
26.)
Organic
molecules usually found in these star-forming regions consist of a single
"backbone" of carbon atoms arranged in a straight chain. But the
carbon structure of isopropyl cyanide branches off, making it the first
interstellar detection of such a molecule, says Rob Garrod, Cornell senior
research associate at the Center for Radiophysics and Space Research.
This
detection opens a new frontier in the complexity of molecules that can be
formed in interstellar space and that might ultimately find their way to the
surfaces of planets, says Garrod. The branched carbon structure of isopropyl
cyanide is a common feature in molecules that are needed for life -- such as
amino acids, which are the building blocks of proteins. This new discovery
lends weight to the idea that biologically crucial molecules, like amino acids
that are commonly found in meteorites, are produced early in the process of
star formation -- even before planets such as Earth are formed.
Garrod,
along with lead author Arnaud Belloche and Karl Menten, both of the Max Planck
Institute for Radio Astronomy, and Holger Müller, of the University of Cologne,
sought to examine the chemical makeup of Sagittarius B2, a region close to the
Milky Way's galactic center and an area rich in complex interstellar organic
molecules.
With ALMA,
the group conducted a full spectral survey -- looking for fingerprints of new
interstellar molecules -- with sensitivity and resolution 10 times greater than
previous surveys.
The purpose
of the ALMA Observatory is to search for cosmic origins through an array of 66
sensitive radio antennas from the high elevation and dry air of northern
Chile's Atacama Desert. The array of radio telescopes works together to form a
gigantic "eye" peering into the cosmos.
"Understanding
the production of organic material at the early stages of star formation is
critical to piecing together the gradual progression from simple molecules to
potentially life-bearing chemistry," said Belloche.
About 50
individual features for isopropyl cyanide (and 120 for normal-propyl cyanide,
its straight-chain sister molecule) were identified in the ALMA spectrum of the
Sagittarius B2 region. The two molecules -- isopropyl cyanide and normal-propyl
cyanide -- are also the largest molecules yet detected in any star-forming
region.
Story
Source:
The above
story is based on materials provided by Cornell University. The original
article was written by Blaine Friedlander. Note: Materials may be edited for
content and length.
Journal
Reference:
A. Belloche,
R. T. Garrod, H. S. P. Muller, K. M. Menten. Detection of a branched alkyl
molecule in the interstellar medium: iso-propyl cyanide. Science, 2014; 345
(6204): 1584 DOI: 10.1126/science.1256678