Astronomers find building blocks of life in red dust of disk surrounding starJanuary 4th, 2008 - 12:27 pm ICT by admin
Washington, Jan 4 (ANI): Astronomers have found the first indications of highly complex organic molecules in the planet-forming disk of red dust surrounding an eight-million-year-old star.
Known as HR 4796A, the star is located in the constellation Centaurus, and is about 220 light years from Earth.
According to the Carnegie Institution, in Washington DC, the observation that the disk surrounding the star has the basic building blocks of life, was made by John Debes and Alycia Weinberger of the Carnegie Institutions Department of Terrestrial Magnetism with Glenn Schneider of the University of Arizona.
Using the Near-Infrared Multi-Object Spectrometer aboard the Hubble Space Telescope, the researchers found that the spectrum of visible and infrared light scattered by the stars dust disk looks very red, the color produced by large organic carbon molecules called tholins.
Tholins do not form naturally on present-day Earth because oxygen in the atmosphere would quickly destroy them, but they are hypothesized to have existed on the primitive Earth billions of years ago and may have been precursors to the biomolecules that make up living organisms.
Though tholins have been detected elsewhere in the solar system, such as in comets and on Saturns moon Titan, where they give the atmosphere a red tinge, the latest study is the first report of tholins outside the solar system.
“Until recently its been hard to know what makes up the dust in a disk from scattered light, so to find tholins this way represents a great leap in our understanding,” said Debes.
The discovery of HR 4796As dust disk in 1991 generated excitement among astronomers, who consider it a prime example of a planetary system caught in the act of formation.
The dust is generated by collisions of small bodies, perhaps similar to the comets or asteroids in our solar system, and which may be coated by the organics. These planetesimals can deliver these building blocks for life to any planets that may also be circling the star.
“Astronomers are just beginning to look for planets around stars much different from the Sun. HR 4796A is twice as massive, nearly twice as hot as the sun, and twenty times more luminous than the Sun,” said Debes.
“Studying this system provides new clues to understanding the different conditions under which planets form and, perhaps, life can evolve,” he added. (ANI)
Tags: alycia weinberger, basic building blocks, carbon molecules, carnegie institution, complex organic molecules, constellation centaurus, dust disk, earth billions, glenn schneider, great leap, hr 4796a, hubble space telescope, john debes, living organisms, planetesimals, primitive earth, red dust, saturns moon titan, scattered light, terrestrial magnetism