Stellar chemistry

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Stellar chemistry is the study of chemical composition of astronomical objects; stars in particular, hence the name stellar chemistry. The significance of stellar chemical composition is an open ended question at this point. Some research asserts that a greater abundance of certain elements (such as carbon, sodium, silicon, and magnesium) in the stellar mass are necessary for a star's inner solar system to be habitable over long periods of time. [1] [2] The hypothesis being that the "abundance of these elements make the star cooler and cause it to evolve more slowly, thereby giving planets in its habitable zone more time to develop life as we know it." [1] Stellar abundance of oxygen also appears to be critical to the length of time newly developed planets exist in a habitable zone around their host star. [2] Researchers postulate that if our own sun had a lower abundance of oxygen, the Earth would have ceased to "live" in a habitable zone a billion years ago, long before complex organisms had the opportunity to evolve. [1]

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Other research

Other research is being or has been done in numerous areas relating to the chemical nature of stars. The formation of stars is of particular interest. Research published in 2009 presents spectroscopic observations of so-called "young stellar objects" viewed in the Large Magellanic Cloud with the Spitzer Space Telescope. This research suggests that water, or, more specifically, ice, plays a large role in the formation of these eventual stars [3]

Others are researching much more tangible ideas relating to stars and chemistry. Research published in 2010 studied the effects of a strong stellar flare on the atmospheric chemistry of an Earth-like planet orbiting an M dwarf star, specifically, the M dwarf AD Leonis. This research simulated the effects an observed flare produced by AD Leonis on April 12, 1985 would have on a hypothetical Earth-like planet. After simulating the effects of both UV radiation and protons on the hypothetical planet's atmosphere, the researchers concluded that "flares may not present a direct hazard for life on the surface of an orbiting habitable planet. Given that AD Leo[nis] is one of the most magnetically active M dwarfs known, this conclusion should apply to planets around other M dwarfs with lower levels of chromospheric activity." [4]

See also

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References

  1. 1 2 3 ScienceShot: For Life's Evolution, Stellar Chemistry Matters
  2. 1 2 The Impact of Stellar Abundance Variations on Stellar Habitable Zone Evolution
  3. Oliveira, J. M.; van Loon, J. T.; Chen, C. H. R.; Tielens, A.; Sloan, G. C.; Woods, P. M.; Kemper, F.; Indebetouw, R.; Gordon, K. D.; Boyer, M. L.; Shiao, B.; Madden, S.; Speck, A. K.; Meixner, M.; Marengo, M., ICE CHEMISTRY IN EMBEDDED YOUNG STELLAR OBJECTS IN THE LARGE MAGELLANIC CLOUD. Astrophysical Journal 2009, 707 (2), 1269–1295.
  4. Segura, A.; Walkowicz, L. M.; Meadows, V.; Kasting, J.; Hawley, S., The Effect of a Strong Stellar Flare on the Atmospheric Chemistry of an Earth-like Planet Orbiting an M Dwarf. Astrobiology 2010, 10 (7), 751–771.