Two newly found space molecules

Alexandra Goho

Adding to the growing body of evidence that space is rich in organic molecules, researchers have detected two new organic chemicals in a large interstellar cloud. Known as Sagittarius B2, this extremely cold mass of star-forming gas and dust is located near the center of the Milky Way galaxy.

To identify the carbon-containing molecules, Jan M. Hollis of the NASA Goddard Space Flight Center in Greenbelt, Md., and his colleagues looked for the emission of specific frequencies of radio waves from the cloud. Different types of molecules emit energy at different frequencies, each producing a unique signal that researchers can detect with powerful telescopes. In the July 20 Astrophysical Journal Letters, the researchers report recording the frequencies associated with two aldehydes called propenal and propanal, which consist of 8 and 10 atoms, respectively, and include three carbons each.

Although astrochemists have found organic molecules in space before (SN: 5/1/04, p. 280: Available to subscribers at http://www.sciencenews.org/articles/20040501/bob9.asp), Hollis says that the evidence of the two aldehydes will help researchers understand how molecular building blocks assemble into more-complex organic molecules in space. For instance, adding two hydrogen atoms to a molecule of propenal yields propanal, and both molecules serve as intermediates in the formation of larger and more-complex compounds.

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References:

2004. Scientists discover two new interstellar molecules: Point to probable pathways for chemical evolution in space. National Radio Astronomy Observatory press release. June 21. Available at http://www.nrao.edu/pr/2004/GBTMolecules/.

Hollis, J.M., et al. 2004. Green bank telescope detection of new interstellar aldehydes: Propenal and propanal. Astrophysical Journal Letters 610(July 20):L21–L24. Abstract available at http://dx.doi.org/10.1086/422911.

Further Readings:

Goho, A. 2004. Space invaders. Science News 165(May 1):280–281. Available to subscribers at http://www.sciencenews.org/articles/20040501/bob9.asp.

Gorman, J. 2000. Sugarcoated news arrives from space. Science News 157(June 24):405. Available to subscribers at http://www.sciencenews.org/articles/20000624/fob3.asp.

Sources:

Jan M. Hollis
NASA Goddard Space Flight Center
Space and Earth Data Computing Division
Mail Code 930
Greenbelt, MD 20771

From Science News, Volume 166, No. 4, July 24, 2004, p. 61.