Traces of Building Blocks of Life in Nearby Galaxies
The goal is to work out when the ingredients for life first existed in the cosmos. “That’s a fascinating question scientifically,” says Chris Churchill of New Mexico State University, who took part in Lawton’s 2006 study, told New Scientist. His group hopes that focusing on dustier galaxies – where organic molecules may form in greater abundance – will help them answer this question.
Astronomers had found a chemical signature of organic compounds in the year 2004, which were called polycyclic aromatic hydrocarbons (PAHs). Located in a galaxy about 10 billion light years away, it appeared as if organic molecules were abundant in the light rays.
In 2006, this idea was questioned by scientist when Brandon Lawton, New Mexico State University, Las Cruces, U.S., performed a survey which failed to find evidence of the bands in six distant galaxies. In the survey, his scientific team looked for a pattern of dark bands—“diffuse interstellar bands (DIBs) in the spectra of light that had passed through the galaxies to reach Earth.” What the DIBs seem to refer to are the results of organic molecules of some sort which are thought to absorb light at certain wavelengths, and thought to be PAHs.
But recent data has been found to show evidence that organic molecules are also common in other parts of the universe. Using the Very Large Telescope in Chile, the University of Victoria, Canada, team led by Sara Ellison, has found another galaxy located about 2 million light years, with the team delving further into the abundance of organic molecules in the galaxy.
Nobody in the study has worked out how and what molecules contribute to the signature of the interstellar bands, which means there is some uncertainty over the composition of the material. But with the advantage of observing the bands in different galaxies, it is possible to pin down the exact molecule or molecules which is considered to be a tremendous break-through.
According to the news article in space.newscientist.com, the very basic thought behind all of this is that astrophysicists believe that organic molecules were present in the cloud formations of dust and gas from which our solar system was formed, providing the raw materials for life on Earth. These molecules are seen throughout our galaxy, which provides for ripened conditions for life in other parts of the Milky Way, or even further.
This entry was posted on Sunday, November 18th, 2007 at 2:03 am and is filed under Public Relations, Space Agency News. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.
