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Journal citation format

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[1]

Article Plans

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I plan on adding a history section to wikipedia's article on Astrochemistry. Namely, I hope to cover crucial chemical findings in the field and the first major application of its main experimental techniques within the field.

History

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As an offshoot of the disciplines of astronomy and chemistry, the history of astrochemistry is founded upon the shared history of the two fields. The development of advanced observational and experimental spectroscopy has allowed for the detection of an ever-increasing array of molecules within solar systems and the surrounding interstellar medium. In turn, the increasing number of chemicals discovered by advancements in spectroscopy and other technologies have increased the size and scale of the chemical space available for astrochemical study.

Spectroscopy

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(Main articles: History of Spectroscopy, Astronomical Spectroscopy)

Observations of solar spectra as performed by Athanasius Kircher (1646), Jan Marek Marci (1648), Robert Boyle (1664), and Francesco Maria Grimaldi (1665) all predated Newton's 1666 work which established the spectral nature of light and resulted in the first spectroscope.[2] Spectroscopy was first used as an astronomical technique in 1802 with the experiments of William Hyde Wollaston, who built a spectrometer to observe the spectral lines present within solar radiation.[3] These spectral lines were later quantified through the work of Joseph Von Fraunhofer.

Spectroscopy was first used to distinguish between different materials after the release of Charles Wheatstone's 1935 report that the sparks given off by different metals have distinct emission spectra.[4] This observation was later built upon by Léon Foucault, who demonstrated in 1849 that identical absorption and emission lines result from the same material at different temperatures. An equivalent statement was independently postulated by Anders Jonas Ångström in his 1853 work Optiska Undersökningar, where it was theorized that luminous gases emit rays of light at the same frequencies as light which they may absorb.

This spectroscopic data began to take upon theoretical importance with Johann Balmer's observation that the spectral lines exhibited by samples of hydrogen followed a simple empirical relationship which came to be known as the Balmer Series. This series, a special case of the more general Rydberg Formula developed by Johannes Rydberg in 1888, was created to describe the spectral lines observed for Hydrogen. Rydberg's work expanded upon this formula by allowing for the calculation of spectral lines for multiple different chemical elements.[5] The theoretical importance granted to these spectroscopic results was greatly expanded upon the development of quantum mechanics, as the theory allowed for these results to be compared to atomic and molecular emission spectra which had been calculated a priori.

Interstellar Chemistry

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While radio astronomy was developed in the 1930s, it was not until 1937 that any substantial evidence arose for the conclusive identification of an interstellar molecule[6] - up until this point, the only chemical species known to exist in interstellar space were atomic. These findings were confirmed in 1940, when McKellar et al. identified and attributed spectroscopic lines in an as-of-then unidentified radio observation to CH and CN molecules in interstellar space.[7] In the thirty years afterwards, a small selection of other molecules were discovered in interstellar space: the most important being OH, discovered in 1963 and significant as a source of interstellar oxygen,[8] and H2CO (Formaldehyde), discovered in 1969 and significant for being the first observed organic, polyatomic molecule in interstellar space[9]

The discovery of interstellar formaldehyde - and later, other molecules with potential biological significance such as water or carbon monoxide - is seen by some as strong supporting evidence for abiogenetic theories of life: specifically, theories which hold that the basic molecular components of life came from extra-terrestrial sources. This has prompted a still ongoing search for interstellar molecules which are either of direct biological importance - such as interstellar glycine, discovered in 2009[10] - or which exhibit biologically relevant properties like Chirality - an example of which (propylene oxide) was discovered in 2016[11] - alongside more basic astrochemical research.

  1. ^ {{cite journal}}: Empty citation (help)
  2. ^ Burns, Thorburn (1987). "Aspects of the development of colorimetric analysis and quantitative molecular spectroscopy in the ultraviolet-visible region". In Burgess, C.; Mielenz, K. D. (eds.). Advances in Standards and Methodology in Spectrophotometry. Burlington: Elsevier Science. p. 1. ISBN 9780444599056.
  3. ^ "A Timeline of Atomic Spectroscopy". {{cite web}}: Unknown parameter |access date= ignored (|access-date= suggested) (help)
  4. ^ Charles Wheatstone (1836). "On the prismatic decomposition of electrical light". Journal of the Franklin Institute. 22 (1): 61–63.
  5. ^ Bohr, N Rydberg's discovery of the spectral laws. Page 16.
  6. ^ Swings, P. & Rosenfeld, L. (1937). "Considerations Regarding Interstellar Molecules". Astrophysical Journal. 86: 483–486.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  7. ^ McKellar, A. (1940). "Evidence for the Molecular Origin of Some Hitherto Unidentified Interstellar Lines". Publications of the Astronomical Society of the Pacific. 52, No. 307: 187.
  8. ^ S. Weinreb, A. H. Barrett, M. L. Meeks & J. C. Henry (1963). "Radio Observations of OH in the Interstellar Medium". Nature. 200: 829–831.{{cite journal}}: CS1 maint: multiple names: authors list (link))
  9. ^ Lewis E. Snyder, David Buhl, B. Zuckerman, and Patrick Palmer (1969). "Microwave Detection of Interstellar Formaldehyde". Phys. Rev. Lett. 22: 679.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  10. ^ "NASA Researchers Make First Discovery of Life's Building Block in Comet". Retrieved 08 June 2017. {{cite web}}: Check date values in: |accessdate= (help)
  11. ^ Brett A. McGuire, P. Brandon Carroll, Ryan A. Loomis, Ian A. Finneran, Philip R. Jewell, Anthony J. Remijan, Geoffrey A. Blake (2016). "Discovery of the interstellar chiral molecule propylene oxide (CH3CHCH2O)". Science. 352 (6292): 1449–1452.{{cite journal}}: CS1 maint: multiple names: authors list (link)