Science Frontiers ONLINE No. 87: May-Jun 1993 | |
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Just as we were getting used to carbonaceous chondrites and tarry comets, we have been hit with cosmic soot and organic asteroids. Truly, it seems as if the universe is one vast factory of complex chemicals. This is not a trivial observation, for it betrays a synthesizing, efflorescent cosmos rather than a universe slowly succumbing to the deepfreezing Second Law of Thermodynamics. Any of these soots and tars wafting down upon the surface of a suitable planet might initiate or accelerate life processes.
Cosmic soot. A 70-year-old astronomical enigma is the origin of the DIBs (Diffuse Interstellar absorption Bands). These dark absorption bands in stellar spectra have never been correlated with known chemical compounds. Now, L. Allamandola and F. Salama (NASA-Ames) find that the DIBs may be due to polycyclic aromatic hydrocarbons! A more digestible descriptor would be "soot," like that found in automobile exhaust and on your barbecued steak.
(Weiss, Peter; "Cosmic Soot Fills Space between the Stars," New Scientist, p. 15, March 13, 1993.)
Organic asteroids. Some asteroids are abnormally red. Newly discovered asteroid 5145 Pholus is 3� times brighter at near-infrared wavelengths than it is in the visible portion of the spectrum. The best explanation so far for this redness is that 5145 Pholus is veneered with organic compounds called "tholins." Tholins are synthesized when methane and other simple chemicals are bathed in ultraviolet and particulate radiations. Tholins have even been dubbed the "first foods" of aspiring new life forms!
(Anonymous; "An Organic Asteroid?" Sky and Telescope, 85:15, 1993.)