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PhysOrg.com wrote:A team of scientists from the Instituto Astrofísica de Canarias (IAC) and the University of Texas has succeeded in identifying one of the most complex organic molecules yet found in the material between the stars, the so-called interstellar medium. The discovery of anthracene could help resolve a decades-old astrophysical mystery concerning the production of organic molecules in space. The researchers report their findings in the journal Monthly Notices of the Royal Astronomical Society.



'We have detected the presence of anthracene molecules in a dense cloud in the direction of the star Cernis 52 in Perseus, about 700 light years from the Sun,' explains Susana Iglesias Groth, the IAC researcher heading the study.

In her opinion, the next step is to investigate the presence of amino acids. Molecules like anthracene are prebiotic, so when they are subjected to ultraviolet radiation and combined with water and ammonia, they could produce amino acids and other compounds essential for the development of life

'Two years ago,' says Iglesias, 'we found proof of the existence of another organic molecule, naphthalene, in the same place, so everything indicates that we have discovered a star formation region rich in prebiotic chemistry.' Until now, anthracene had been detected only in meteorites and never in the interstellar medium. Oxidized forms of this molecule are common in living systems and are biochemically active. On our planet, oxidized anthracene is a basic component of aloe and has anti-inflammatory properties.

The new finding suggests that a good part of the key components in terrestrial prebiotic chemistry could be present in interstellar matter.

Since the 1980s, hundreds of bands found in the spectrum of the interstellar medium, known as diffuse spectroscopic bands, have been known to be associated with interstellar matter, but their origin has not been identified until now. This discovery indicates that they could result from molecular forms based on anthracene or naphthalene. Since they are widely distributed in interstellar space, they might have played a key role in the production of many of the organic molecules present at the time of the formation of the Solar System.

The results are based on observations carried out at the William Herschel Telescope at Roque de los Muchachos Observatory on La Palma in the Canary Islands and with the Hobby-Eberly Telescope in Texas in the United States.

More information: The new work appears in the paper “Anthracene cations toward the Perseus molecular complex", S. Iglesias Groth S., Manchado A., Rebolo R., González J. I., García Hernández A. (IAC); Lambert D. L. (McDonald Observatory, University of Texas), Monthly Notices of the Royal Astronomical Society, in press. A preprint of the paper can be seen at http://arxiv.org/abs/1005.4388

arxiv.org wrote:We report the discovery of a new broad interstellar (or circumstellar) band at 7088.8 +- 2.0 \AA coincident to within the measurement uncertainties with the strongest band of the anthracene cation (C$_{14}$H$_{10}$$^+$) as measured in gas-phase laboratory spectroscopy at low temperatures (Sukhorukov et al.2004). The band is detected in the line of sight of star Cernis 52, a likely member of the very young star cluster IC 348, and is probably associated with cold absorbing material in a intervening molecular cloud of the Perseus star forming region where various experiments have recently detected anomalous microwave emission. From the measured intensity and available oscillator strength we find a column density of N$_{an^+}$= 1.1(+-0.4) x 10$^{13}$ cm$^{-2}$ implying that ~0.008% of the carbon in the cloud could be in the form of C$_{14}$H$_{10}$$^+$. A similar abundance has been recently claimed for the naphthalene cation (Iglesias-Groth et al. 2008) in this cloud. This is the first location outside the Solar System where specific PAHs are identified. We report observations of interstellar lines of CH and CH$^+$ that support a rather high column density for these species and for molecular hydrogen. The strength ratio of the two prominent diffuse interstellar bands at 5780 and 5797 \AA suggests the presence of a ``zeta'' type cloud in the line of sight (consistent with steep far-UV extinction and high molecular content). The presence of PAH cations and other related hydrogenated carbon molecules which are likely to occur in this type of clouds reinforce the suggestion that electric dipole radiation from fast spinning PAHs is responsible of the anomalous microwave emission detected toward Perseus.

frigidmagi wrote:I'm not sure I understood any of that but I got there are carbon molecules and the radiation they produce is somehow making microwave emissions?

arxiv.org wrote:We report the discovery of a new broad interstellar (or circumstellar) band at 7088.8 +- 2.0 \AA coincident to within the measurement uncertainties with the strongest band of the anthracene cation (C$_{14}$H$_{10}$$^+$) as measured in gas-phase laboratory spectroscopy at low temperatures (Sukhorukov et al.2004). The band is detected in the line of sight of star Cernis 52, a likely member of the very young star cluster IC 348, and is probably associated with cold absorbing material in a intervening molecular cloud of the Perseus star forming region where various experiments have recently detected anomalous microwave emission. From the measured intensity and available oscillator strength we find a column density of N$_{an^+}$= 1.1(+-0.4) x 10$^{13}$ cm$^{-2}$ implying that ~0.008% of the carbon in the cloud could be in the form of C$_{14}$H$_{10}$$^+$. A similar abundance has been recently claimed for the naphthalene cation (Iglesias-Groth et al. 2008) in this cloud. This is the first location outside the Solar System where specific PAHs are identified. We report observations of interstellar lines of CH and CH$^+$ that support a rather high column density for these species and for molecular hydrogen. The strength ratio of the two prominent diffuse interstellar bands at 5780 and 5797 \AA suggests the presence of a ``zeta'' type cloud in the line of sight (consistent with steep far-UV extinction and high molecular content). The presence of PAH cations and other related hydrogenated carbon molecules which are likely to occur in this type of clouds reinforce the suggestion that electric dipole radiation from fast spinning PAHs is responsible of the anomalous microwave emission detected toward Perseus.

Mayabird wrote:Oh for crying out loud, I understood it and chemistry was my worst subject in college.

Oh for crying out loud, I understood it and chemistry was my worst subject in college.

If this stuff gets some H20 and NH3,(Water and ammonia) the heavy bombardment it will get by ultraviolet light, because open space lacks protection like an atmosphere, it can and likely will become amino acids. Enough amino acids, they will start forming proteins. Most basic parts of life. As we look for each step further, we are approaching greater and greater odds that life isn't even close to what we thought. Yes, this includes the possibility of lifeforms in open space, or clouds of nebulas or similar. Or even catching rides on asteroids and comets, and finding planets where life starts getting delightfully complex.

I recall a theory that Earth itself may have been seeded with extraterrestrial life forms at some point early on in its history. I rather assume that this new finding increases those chances?

As we look for each step further, we are approaching greater and greater odds that life isn't even close to what we thought. Yes, this includes the possibility of lifeforms in open space, or clouds of nebulas or similar. Or even catching rides on asteroids and comets, and finding planets where life starts getting delightfully complex.

frigidmagi wrote:Thank you Martin. I got that. We would be talking mostly single celled life forms right? That's pretty damn amazing given what I know of space (we don't call it the Void for the poetry).