World Library  
Flag as Inappropriate
Email this Article

List of interstellar and circumstellar molecules

Article Id: WHEBN0000921245
Reproduction Date:

Title: List of interstellar and circumstellar molecules  
Author: World Heritage Encyclopedia
Language: English
Subject: WikiProject Academic Journals/Journals cited by Wikipedia/A60, Intergalactic dust, Buckminsterfullerene, PAH world hypothesis, Benzene
Collection: Astrochemistry, Chemistry-Related Lists, Interstellar Media, Molecules
Publisher: World Heritage Encyclopedia

List of interstellar and circumstellar molecules

This is a list of molecules that have been detected in the interstellar medium and circumstellar envelopes, grouped by the number of component atoms. The chemical formula is listed for each detected compound, along with any ionized form that has also been observed.


  • Detection 1
    • History 1.1
  • Molecules 2
    • Diatomic (43) 2.1
    • Triatomic (43) 2.2
    • Four atoms (27) 2.3
    • Five atoms (18) 2.4
    • Six atoms (16) 2.5
    • Seven atoms (9) 2.6
    • Eight atoms (11) 2.7
    • Nine atoms (10) 2.8
    • Ten or more atoms (15) 2.9
  • Deuterated molecules (17) 3
  • Unconfirmed (13) 4
  • See also 5
  • References 6
  • External links 7


The molecules listed below were detected by spectroscopy. Their spectral features are generated by transitions of component electrons between different energy levels, or by rotational or vibrational spectra. Detection usually occurs in radio, microwave, or infrared portions of the spectrum.[1]

Interstellar molecules are formed by chemical reactions within very sparse interstellar or circumstellar clouds of dust and gas. Usually this occurs when a molecule becomes ionized, often as the result of an interaction with a cosmic ray. This positively charged molecule then draws in a nearby reactant by electrostatic attraction of the neutral molecule's electrons. Molecules can also be generated by reactions between neutral atoms and molecules, although this process is generally slower.[2] The dust plays a critical role of shielding the molecules from the ionizing effect of ultraviolet radiation emitted by stars.[3]


The chemistry of life may have begun shortly after the Big Bang, 13.8 billion years ago, during a habitable epoch when the Universe was only 10–17 million years old.[4][5]

The first carbon-containing molecule detected in the interstellar medium was the

  • Woon, David E. (October 1, 2010). "Interstellar and Circumstellar Molecules". Retrieved 2010-10-04. 
  • "Molecules in Space".  
  • Dworkin, Jason P. (February 1, 2007). "Interstellar Molecules". NASA's Cosmic Ice Lab. Retrieved 2010-12-23. 
  • Wootten, Al (November 2005). "The 129 reported interstellar and circumstellar molecules". National Radio Astronomy Observatory. Retrieved 2007-02-13. 
  • Lovas, F. J.; Dragoset, R. A. (February 2004). "NIST Recommended Rest Frequencies for Observed Interstellar Molecular Microwave Transitions, 2002 Revision". National Institute of Standards and Technology. Retrieved 2007-02-13. 

External links

  1. ^ Shu, Frank H. (1982), The Physical Universe: An Introduction to Astronomy, University Science Books,  
  2. ^ a b c Dalgarno, A. (2006), "Interstellar Chemistry Special Feature: The galactic cosmic ray ionization rate", Proceedings of the National Academy of Sciences 103 (33): 12269–12273,  
  3. ^ Brown, Laurie M.; Pais, Abraham; Pippard, A. B. (1995), "The physics of the interstellar medium", Twentieth Century Physics (2nd ed.), CRC Press, p. 1765,  
  4. ^  
  5. ^  
  6. ^ Woon, D. E. (May 2005), Methylidyne radical, The Astrochemist, retrieved 2007-02-13 
  7. ^ Ruaud, M.; Loison, J.C.; Hickson, K.M.; Gratier, P.; Hersant, F.; Wakelam, V. (22 December 2014). "Modeling Complex Organic Molecules in dense regions: Eley-Rideal and complex induced reaction" ( 
  8. ^ N.C. Wickramasinghe, Formaldehyde Polymers in Interstellar Space, Nature, 252, 462, 1974
  9. ^ F. Hoyle and N.C. Wickramasinghe, Identification of the lambda 2200A interstellar absorption feature, Nature, 270, 323, 1977
  10. ^ a b c d Battersby, S. (2004). "Space molecules point to organic origins".  
  11. ^ a b Mulas, G.; Malloci, G.; Joblin, C.; Toublanc, D. (2006). "Estimated IR and phosphorescence emission fluxes for specific polycyclic aromatic hydrocarbons in the Red Rectangle". Astronomy and Astrophysics 446 (2): 537–549.  
  12. ^ García-Hernández, D. A.; Manchado, A.; García-Lario, P.; Stanghellini, L.; Villaver, E.; Shaw, R. A.; Szczerba, R.; Perea-Calderón, J. V. (2010-10-28). "Formation Of Fullerenes In H-Containing Planatary Nebulae".  
  13. ^ Atkinson, Nancy (2010-10-27). "Buckyballs Could Be Plentiful in the Universe".  
  14. ^ a b c Chow, Denise (26 October 2011). "Discovery: Cosmic Dust Contains Organic Matter from Stars".  
  15. ^  
  16. ^ Kwok, Sun; Zhang, Yong (26 October 2011). "Mixed aromatic–aliphatic organic nanoparticles as carriers of unidentified infrared emission features".  
  17. ^ Gallori, Enzo (November 2010). "Astrochemistry and the origin of genetic material". Rendiconti Lincei 22 (2): 113–118.  
  18. ^ Martins, Zita (February 2011). "Organic Chemistry of Carbonaceous Meteorites". Elements 7 (1): 35–40.  
  19. ^ Than, Ker (August 29, 2012). "Sugar Found In Space". National Geographic. Retrieved August 31, 2012. 
  20. ^ Staff (August 29, 2012). "Sweet! Astronomers spot sugar molecule near star".  
  21. ^ Jørgensen, J. K.; Favre, C.; Bisschop, S.; Bourke, T.; Dishoeck, E.; Schmalzl, M. (2012). "Detection of the simplest sugar, glycolaldehyde, in a solar-type protostar with ALMA" (PDF). The Astrophysical Journal Letters. eprint 757: L4.  
  22. ^ a b Staff (September 20, 2012). "NASA Cooks Up Icy Organics to Mimic Life's Origins".  
  23. ^ a b Gudipati, Murthy S.; Yang, Rui (September 1, 2012). "In-Situ Probing Of Radiation-Induced Processing Of Organics In Astrophysical Ice Analogs—Novel Laser Desorption Laser Ionization Time-Of-Flight Mass Spectroscopic Studies".  
  24. ^ Clavin, Whitney (10 February 2015). "Why Comets Are Like Deep Fried Ice Cream".  
  25. ^ López-Puertas, Manuel (June 6, 2013). "PAH's in Titan's Upper Atmosphere".  
  26. ^
  27. ^ Cummins, S. E.; Linke, R. A.; Thaddeus, P. (1986), "A survey of the millimeter-wave spectrum of Sagittarius B2", Astrophysical Journal Supplement Series 60: 819–878,  
  28. ^ Kaler, James B. (2002), The hundred greatest stars, Copernicus Series, Springer,  
  29. ^ Marlaire, Ruth (3 March 2015). "NASA Ames Reproduces the Building Blocks of Life in Laboratory".  
  30. ^ a b Klemperer, William (2011), "Astronomical Chemistry", Annual Review of Physical Chemistry 62: 173–184,  
  31. ^ The Structure of Molecular Cloud Cores, Centre for Astrophysics and Planetary Science, University of Kent, retrieved 2007-02-16 
  32. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj ak al am Ziurys, Lucy M. (2006), "The chemistry in circumstellar envelopes of evolved stars: Following the origin of the elements to the origin of life", Proceedings of the National Academy of Sciences 103 (33): 12274–12279,  
  33. ^ a b c Cernicharo, J.; Guelin, M. (1987), "Metals in IRC+10216 - Detection of NaCl, AlCl, and KCl, and tentative detection of AlF", Astronomy and Astrophysics 183 (1): L10–L12,  
  34. ^ Ziurys, L. M.; Apponi, A. J.; Phillips, T. G. (1994), "Exotic fluoride molecules in IRC +10216: Confirmation of AlF and searches for MgF and CaF", Astrophysical Journal 433 (2): 729–732,  
  35. ^ Tenenbaum, E. D.; Ziurys, L. M. (2009), "Millimeter Detection of AlO (X2Σ+): Metal Oxide Chemistry in the Envelope of VY Canis Majoris", Astrophysical Journal 694: L59–L63,  
  36. ^ Barlow, M. J.; Swinyard, B. M.; Owen, P. J.; Cernicharo, J.; Gomez, H. L.; Ivison, R. J.; Lim, T. L.; Matsuura, M.; Miller, S.; Olofsson, G.; Polehampton, E. T. (2013), "Detection of a Noble Gas Molecular Ion, 36ArH+, in the Crab Nebula",  
  37. ^ Quenqua, Douglas (13 December 2013). "Noble Molecules Found in Space".  
  38. ^ a b c Lambert, D. L.; Sheffer, Y.; Federman, S. R. (1995), "Hubble Space Telescope observations of C2 molecules in diffuse interstellar clouds", Astrophysical Journal 438: 740–749,  
  39. ^ a b c Galazutdinov, G. A.; Musaev, F. A.; Krelowski, J. (2001), "On the detection of the linear C5 molecule in the interstellar medium", Monthly Notices of the Royal Astronomical Society 325 (4): 1332–1334,  
  40. ^ Neufeld, D. A.; et al. (2006), "Discovery of interstellar CF+", Astronomy and Astrophysics 454 (2): L37–L40,  
  41. ^ a b Adams, Walter S. (1941), "Some Results with the COUDÉ Spectrograph of the Mount Wilson Observatory", Astrophysical Journal 93: 11–23,  
  42. ^ a b c d e f Smith, D. (1988), "Formation and Destruction of Molecular Ions in Interstellar Clouds", Philosophical Transactions of the Royal Society of London 324 (1578): 257–273,  
  43. ^ a b c d e f g h Fuente, A.; et al. (2005), "Photon-dominated Chemistry in the Nucleus of M82: Widespread HOC+ Emission in the Inner 650 Parsec Disk", Astrophysical Journal 619 (2): L155–L158,  
  44. ^ a b Guelin, M.; Cernicharo, J.; Paubert, G.; Turner, B. E. (1990), "Free CP in IRC + 10216", Astronomy and Astrophysics 230: L9–L11,  
  45. ^ a b c Dopita, Michael A.; Sutherland, Ralph S. (2003), Astrophysics of the diffuse universe, Springer-Verlag,  
  46. ^ Agúndez, M.; et al. (2010-07-30), , the smallest observed molecular anion""Astronomical identification of CN, Astronomy & Astrophysics 517: L2,  
  47. ^ Khan, Amina. "Did two planets around nearby star collide? Toxic gas holds hints".  
  48. ^ Dent, W.R.F.; Wyatt, M.C.;Roberge, A.; Augereau,J.-C.; Casassus, S.;Corder, S.; Greaves, J.S.; de Gregorio-Monsalvo, I; Hales, A.; Jackson, A.P.; Hughes, A. Meredith; Lagrange, A.-M; Matthews, B.; Wilner, D. (March 6, 2014). "Molecular Gas Clumps from the Destruction of Icy Bodies in the β Pictoris Debris Disk".  
  49. ^ Latter, W. B.; Walker, C. K.; Maloney, P. R. (1993), "Detection of the Carbon Monoxide Ion (CO+) in the Interstellar Medium and a Planetary Nebula", Astrophysical Journal Letters 419: L97,  
  50. ^ Furuya, R. S.; et al. (2003), "Interferometric observations of FeO towards Sagittarius B2", Astronomy and Astrophysics 409 (2): L21–L24,  
  51. ^ Adams, Walter S. (1970), "Rocket Observation of Interstellar Molecular Hydrogen", Astrophysical Journal 161: L81–L85,  
  52. ^ Blake, G. A.; Keene, J.; Phillips, T. G. (1985), "Chlorine in dense interstellar clouds - The abundance of HCl in OMC-1", Astrophysical Journal, Part 1 295: 501–506,  
  53. ^ De Luca, M.; Gupta, H.; Neufeld, D.; Gerin, M.; Teyssier, D.; Drouin, B. J.; Pearson, J. C.; Lis, D. C.; et al. (2012), "Herschel/HIFI Discovery of HCl+ in the Interstellar Medium", The Astrophysical Journal Letters 751 (2): L37,  
  54. ^ Neufeld, David A.; et al. (1997), "Discovery of Interstellar Hydrogen Fluoride", Astrophysical Journal Letters 488 (2): L141–L144,  
  55. ^ Wyrowski, F.; et al. (2009), "First interstellar detection of OH+", Astronomy & Astrophysics 518: A26,  
  56. ^ a b Meyer, D. M.; Roth, K. C. (1991), "Discovery of interstellar NH", Astrophysical Journal, Part 2 - Letters 376: L49–L52,  
  57. ^ Wagenblast, R.; et al. (January 1993), "On the origin of NH in diffuse interstellar clouds", Monthly Notices of the Royal Astronomical Society 260 (2): 420–424,  
  58. ^ (June 9, 2004), Astronomers Detect Molecular Nitrogen Outside Solar System, Space Daily, retrieved 2010-06-25 
  59. ^ Knauth, D. C; et al. (2004), abundance towards HD 124314 from far-ultraviolet observations"2"The interstellar N, Nature 429 (6992): 636–638,  
  60. ^ McGonagle, D.; et al. (1990), "Detection of nitric oxide in the dark cloud L134N", Astrophysical Journal, Part 1 359: 121–124,  
  61. ^ Whiteoak, J. B.; Gardner, F. F. (1985), "Interstellar NaI absorption towards the stellar association ARA OB1", Astronomical Society of Australia, Proceedings (Sydney) 6 (2): 164–171,  
  62. ^ Staff writers (March 27, 2007), Elusive oxygen molecule finally discovered in interstellar space,, retrieved 2007-04-02 
  63. ^ Ziurys, L. M. (1987), "Detection of interstellar PN - The first phosphorus-bearing species observed in molecular clouds", Astrophysical Journal, Part 2 - Letters to the Editor 321: L81–L85,  
  64. ^ Tenenbaum, E. D.; Woolf, N. J.; Ziurys, L. M. (2007), "Identification of phosphorus monoxide (X 2 Pi r) in VY Canis Majoris: Detection of the first PO bond in space", Astrophysical Journal, Part 2 - Letters to the Editor 666: L29–L32,  
  65. ^ Yamamura, S. T.; Kawaguchi, K.; Ridgway, S. T. (2000), "Identification of SH v=1 Ro-vibrational Lines in R Andromedae", The Astrophysical Journal 528 (1): L33–L36,  
  66. ^ Menten, K. M.; et al. (2011), and HCl"+CH13, a New Widespread Interstellar Radical, +"Submillimeter Absorption from SH, Astronomy & Astrophysics 525: A77,  
  67. ^ a b c Pascoli, G.; Comeau, M. (1995), "Silicon Carbide in Circumstellar Environment", Astrophysics and Space Science 226: 149–163,  
  68. ^ a b Kamiński, T.; et al. (2013), "Pure rotational spectra of TiO and TiO2 in VY Canis Majoris", Astronomy and Astrophysics 551: A113,  
  69. ^ a b Geballe, T. R.; Oka, T. (1996), "Detection of H3+ in Interstellar Space", Nature 384 (6607): 334–335,  
  70. ^ Tenenbaum, E. D.; Ziurys, L. M. (2010), "Exotic Metal Molecules in Oxygen-rich Envelopes: Detection of AlOH (X1Σ+) in VY Canis Majoris", Astrophysical Journal 712: L93–L97,  
  71. ^ Anderson, J. K.; et al. (2014), "Detection of CCN (X2Πr) in IRC+10216: Constraining Carbon-chain Chemistry", Astrophysical Journal 795: L1,  
  72. ^ Ohishi, Masatoshi, Masatoshi; et al. (1991), "Detection of a new carbon-chain molecule, CCO", Astrophysical Journal, Part 2 - Letters 380: L39–L42,  
  73. ^ a b c d Irvine, William M.; et al. (1988), "Newly detected molecules in dense interstellar clouds", Astrophysical Letters and Communications 26: 167–180,  
  74. ^ a b Halfen, D. T.; Clouthier, D. J.; Ziurys, L. M. (2008), "Detection of the CCP Radical (X 2Πr) in IRC +10216: A New Interstellar Phosphorus-containing Species", Astrophysical Journal 677 (2): L101–L104,  
  75. ^ Whittet, D. C. B.; Walker, H. J. (1991), "On the occurrence of carbon dioxide in interstellar grain mantles and ion-molecule chemistry", Monthly Notices of the Royal Astronomical Society 252: 63–67,  
  76. ^ Zack, L. N.; Halfen, D. T.; Ziurys, L. M. (June 2011), "Detection of FeCN (X 4Δi) in IRC+10216: A New Interstellar Molecule", The Astrophysical Journal Letters 733 (2): L36,  
  77. ^ Lis, D. C.; et al. (2010-10-01), "Herschel/HIFI discovery of interstellar chloronium (H2Cl+)", Astronomy & Astrophysics 521: L9,  
  78. ^ Europe's space telescope ISO finds water in distant places, ESO, April 29, 1997, archived from the original on 2006-12-22, retrieved 2007-02-08 
  79. ^ Ossenkopf, V.; et al. (2010), "Detection of interstellar oxidaniumyl: Abundant H2O+ towards the star-forming regions DR21, Sgr B2, and NGC6334", Astronomy & Astrophysics 518: L111,  
  80. ^ Parise, B.; Bergman, P.; Du, F. (2012), "Detection of the hydroperoxyl radical HO2 toward ρ Ophiuchi A. Additional constraints on the water chemical network", Astronomy & Astrophysics Letters 541: L11–L14,  
  81. ^ Snyder, L. E.; Buhl, D. (1971), "Observations of Radio Emission from Interstellar Hydrogen Cyanide", Astrophysical Journal 163: L47–L52,  
  82. ^ a b Schilke, P.; Benford, D. J.; Hunter, T. R.; Lis, D. C., Phillips, T. G.; Phillips, T. G. (2001), "A Line Survey of Orion-KL from 607 to 725 GHz", Astrophysical Journal Supplement Series 132 (2): 281–364,  
  83. ^ a b Schenewerk, M. S.; Snyder, L. E.; Hjalmarson, A. (1986), "Interstellar HCO - Detection of the missing 3 millimeter quartet", Astrophysical Journal, Part 2 - Letters to the Editor 303: L71–L74,  
  84. ^ a b c d e f Kawaguchi, Kentarou; et al. (1994), "Detection of a new molecular ion HC3NH(+) in TMC-1", Astrophysical Journal 420: L95,  
  85. ^ Agúndez, M.; Cernicharo, J.; Guélin, M. (2007), "Discovery of Phosphaethyne (HCP) in Space: Phosphorus Chemistry in Circumstellar Envelopes", The Astrophysical Journal 662 (2): L91,  
  86. ^ Schilke, P.; Comito, C.; Thorwirth, S. (2003), "First Detection of Vibrationally Excited HNC in Space", The Astrophysical Journal 582 (2): L101–L104,  
  87. ^ Hollis, J. M.; et al. (1991), "Interstellar HNO: Confirming the Identification - Atoms, ions and molecules: New results in spectral line astrophysics", Atoms (San Francisco: ASP) 16: 407–412,  
  88. ^ van Dishoeck, Ewine F.; et al. (1993), "Detection of the Interstellar NH 2 Radical", Astrophysical Journal, Part 2 - Letters 416: L83–L86,  
  89. ^ Womack, M.; Ziurys, L. M.; Wyckoff, S. (1992), "A survey of N2H(+) in dense clouds - Implications for interstellar nitrogen and ion-molecule chemistry", Astrophysical Journal, Part 1 387: 417–429,  
  90. ^ Ziurys, L. M.; et al. (1994), "Detection of interstellar N2O: A new molecule containing an N-O bond", Astrophysical Journal, Part 2 - Letters 436: L181–L184,  
  91. ^ Hollis, J. M.; Rhodes, P. J. (November 1, 1982), "Detection of interstellar sodium hydroxide in self-absorption toward the galactic center", Astrophysical Journal, Part 2 - Letters to the Editor 262: L1–L5,  
  92. ^ Goldsmith, P. F.; Linke, R. A. (1981), "A study of interstellar carbonyl sulfide", Astrophysical Journal, Part 1 245: 482–494,  
  93. ^ Phillips, T. G.; Knapp, G. R. (1980), "Interstellar Ozone", American Astronomical Society Bulletin 12: 440,  
  94. ^ a b c d e f g h i j Johansson, L. E. B.; et al. (1984), "Spectral scan of Orion A and IRC+10216 from 72 to 91 GHz", Astronomy and Astrophysics 130 (2): 227–256,  
  95. ^ Cernicharo, José; et al. (2015), "Discovery of SiCSi in IRC+10216: a Missing Link Between Gas and Dust Carriers OF Si–C Bonds", Astrophysical Journal Letters 806: L3,  
  96. ^ Guélin, M.; et al. (2004), "Astronomical detection of the free radical SiCN", Astronomy and Astrophysics 363: L9–L12,  
  97. ^ Guélin, M.; et al. (2004), "Detection of the SiNC radical in IRC+10216", Astronomy and Astrophysics 426 (2): L49–L52,  
  98. ^ a b Snyder, Lewis E.; et al. (1999), "Microwave Detection of Interstellar Formaldehyde", Physical Review Letters 61 (2): 77–115,  
  99. ^ Feuchtgruber, H.; et al. (June 2000), "Detection of Interstellar CH3", The Astrophysical Journal 535 (2): L111–L114,  
  100. ^ a b Irvine, W. M.; et al. (1984), "Confirmation of the Existence of Two New Interstellar Molecules: C3H and C3O", Bulletin of the American Astronomical Society 16: 877,  
  101. ^ Pety, J.; et al. (2012), "The IRAM-30 m line survey of the Horsehead PDR. II. First detection of the l-C3MH+ hydrocarbon cation", Astronomy & Astrophysica 548: A68,  
  102. ^ Mangum, J. G.; Wootten, A. (1990), "Observations of the cyclic C3H radical in the interstellar medium", Astronomy and Astrophysics 239: 319–325,  
  103. ^ Wootten, Alwyn; et al. (1991), "Detection of interstellar H3O(+) - A confirming line", Astrophysical Journal, Part 2 - Letters 380: L79–L83,  
  104. ^ Ridgway, S. T.; et al. (1976), "Circumstellar acetylene in the infrared spectrum of IRC+10216", Nature 264: 345, 346,  
  105. ^ Ohishi, Masatoshi; et al. (1994), "Detection of a new interstellar molecule, H2CN", Astrophysical Journal, Part 2 - Letters 427: L51–L54,  
  106. ^ Minh, Y. C.; Irvine, W. M.; Brewer, M. K. (1991), "H2CS abundances and ortho-to-para ratios in interstellar clouds", Astronomy and Astrophysics 244: 181–189,  
  107. ^ Guelin, M.; Cernicharo, J. (1991), "Astronomical detection of the HCCN radical - Toward a new family of carbon-chain molecules?", Astronomy and Astrophysics 244: L21–L24,  
  108. ^ Agúndez, M.; et al. (2015), "Discovery of interstellar ketenyl (HCCO), a surprisingly abundant radical", Astronomy and Astrophysics 577: A5,  
  109. ^ Minh, Y. C.; Irvine, W. M.; Ziurys, L. M. (1988), "Observations of interstellar HOCO(+) - Abundance enhancements toward the Galactic center", Astrophysical Journal, Part 1 334: 175–181,  
  110. ^ Marcelino, Núria; et al. (2009), "Discovery of fulminic acid, HCNO, in dark clouds", Astrophysical Journal 690: L27–L30,  
  111. ^ Brünken, S.; et al. (2010-07-22), "Interstellar HOCN in the Galactic center region", Astronomy & Astrophysics 516: A109,  
  112. ^ Bergman; Parise; Liseau; Larsson; Olofsson; Menten; Güsten (2011), "Detection of interstellar hydrogen peroxide", Astronomy & Astrophysics 531: L8,  
  113. ^ a b Frerking, M. A.; Linke, R. A.; Thaddeus, P. (1979), "Interstellar isothiocyanic acid", Astrophysical Journal, Part 2 - Letters to the Editor 234: L143–L145,  
  114. ^ a b Nguyen-Q-Rieu; Graham, D.; Bujarrabal, V. (1984), "Ammonia and cyanotriacetylene in the envelopes of CRL 2688 and IRC + 10216", Astronomy and Astrophysics 138 (1): L5–L8,  
  115. ^ Halfen, D. T.; et al. (September 2009), "Detection of a New Interstellar Molecule: Thiocyanic Acid HSCN", The Astrophysical Journal Letters 702 (2): L124–L127,  
  116. ^ Cabezas, C.; et al. (2013), "Laboratory and Astronomical Discovery of Hydromagnesium Isocyanide", Astrophysical Journal 775: 133,  
  117. ^ Butterworth, Anna L.; et al. (2004), "Combined element (H and C) stable isotope ratios of methane in carbonaceous chondrites", Monthly Notices of the Royal Astronomical Society 347 (3): 807–812,  
  118. ^
  119. ^
  120. ^ Cernicharo, J.; Marcelino, N.; Roueff, E.; Gerin, M.; Jiménez-Escobar, A.; Muñoz Caro, G. M. (2012), "Discovery of the Methoxy Radical, CH3O, toward B1: Dust Grain and Gas-phase Chemistry in Cold Dark Clouds", The Astrophysical Journal Letters 759 (2): L43–L46,  
  121. ^ a b c d e f g h Finley, Dave (August 7, 2006), Researchers Use NRAO Telescope to Study Formation Of Chemical Precursors to Life, National Radio Astronomy Observatory, retrieved 2006-08-10 
  122. ^ a b c d e f g Fossé, David; et al. (2001), "Molecular Carbon Chains and Rings in TMC-1", Astrophysical Journal 552 (1): 168–174,  
  123. ^ Dickens, J. E.; et al. (1997), "Hydrogenation of Interstellar Molecules: A Survey for Methylenimine (CH2NH)", Astrophysical Journal 479 (1 Pt 1): 307–12,  
  124. ^ McGuire, B.A.; et al. (2012), "Interstellar Carbodiimide (HNCNH): A New Astronomical Detection from the GBT PRIMOS Survey via Maser Emission Features", The Astrophysical Journal Letters 758 (2): L33–L38,  
  125. ^ Ohishi, Masatoshi; et al. (1996), "Detection of a New Interstellar Molecular Ion, H2COH+ (Protonated Formaldehyde)", Astrophysical Journal 471 (1): L61–4,  
  126. ^ Cernicharo, J.; et al. (2007), "Astronomical detection of C4H, the second interstellar anion", Astronomy and Astrophysics 61 (2): L37–L40,  
  127. ^ a b Walmsley, C. M.; Winnewisser, G.; Toelle, F. (1990), "Cyanoacetylene and cyanodiacetylene in interstellar clouds", Astronomy and Astrophysics 81 (1–2): 245–250,  
  128. ^ Kawaguchi, Kentarou; et al. (1992), "Detection of isocyanoacetylene HCCNC in TMC-1", Astrophysical Journal 386 (2): L51–L53,  
  129. ^ Turner, B. E.; et al. (1975), "Microwave detection of interstellar cyanamide", Astrophysical Journal 201: L149–L152,  
  130. ^ Remijan, Anthony J.; et al. (2008), "Detection of interstellar cyanoformaldehyde (CNCHO)", Astrophysical Journal 675 (2): L85–L88,  
  131. ^ Goldhaber, D. M.; Betz, A. L. (1984), "Silane in IRC +10216", Astrophysical Journal, Part 2 - Letters to the Editor 279: –L55–L58,  
  132. ^ a b c d Hollis, J. M.; et al. (2006), "Detection of Acetamide (CH3CONH2): The Largest Interstellar Molecule with a Peptide Bond", Astrophysical Journal 643 (1): L25–L28,  
  133. ^ Zaleski, D. P.; et al. (2013), "Detection of E-Cyanomethanimine toward Sagittarius B2(N) in the Green Bank Telescope PRIMOS Survey", Astrophysical Journal Letters 765: L109,  
  134. ^ Betz, A. L. (1981), "Ethylene in IRC +10216", Astrophysical Journal, Part 2 - Letters to the Editor 244: –L105,  
  135. ^ a b c d e Remijan, Anthony J.; et al. (2005), "Interstellar Isomers: The Importance of Bonding Energy Differences", Astrophysical Journal 632 (1): 333–339,  
  136. ^ "Complex Organic Molecules Discovered in Infant Star System". NRAO (Astrobiology Web). 8 April 2015. Retrieved 2015-04-09. 
  137. ^ a b c Cernicharo, José; et al. (1997), , and Benzene in CRL 618"2H6, C2H4"Infrared Space Observatory's Discovery of C, Astrophysical Journal Letters 546 (2): L123–L126,  
  138. ^ Guelin, M.; Neininger, N.; Cernicharo, J. (1998), "Astronomical detection of the cyanobutadiynyl radical C_5N", Astronomy and Astrophysics 335: L1–L4,  
  139. ^ Irvine, W. M.; et al. (1988), "A new interstellar polyatomic molecule - Detection of propynal in the cold cloud TMC-1", Astrophysical Journal, Part 2 - Letters 335: L89–L93,  
  140. ^ a b c d Agúndez, M.; et al. (2014), "New molecules in IRC +10216: confirmation of C5S and tentative identification of MgCCH, NCCP, and SiH3CN", Astronomy and Astrophysics 570: A45,  
  141. ^ a b Scientists Toast the Discovery of Vinyl Alcohol in Interstellar Space, National Radio Astronomy Observatory, October 1, 2001, retrieved 2006-12-20 
  142. ^ a b Dickens, J. E.; et al. (1997), "Detection of Interstellar Ethylene Oxide (c-C2H4O)", The Astrophysical Journal 489 (2): 753–757,  
  143. ^ Kaifu, N.; Takagi, K.; Kojima, T. (1975), "Excitation of interstellar methylamine", Astrophysical Journal 198: L85–L88,  
  144. ^ McCarthy, M. C.; et al. (2006), "Laboratory and Astronomical Identification of the Negative Molecular Ion C6H", Astrophysical Journal 652 (2): L141–L144,  
  145. ^ a b Mehringer, David M.; et al. (1997), "Detection and Confirmation of Interstellar Acetic Acid", Astrophysical Journal Letters 480: L71,  
  146. ^ a b Lovas, F. J.; et al. (2006), "Hyperfine Structure Identification of Interstellar Cyanoallene toward TMC-1", Astrophysical Journal Letters 637 (1): L37–L40,  
  147. ^ a b Sincell, Mark (June 27, 2006), The Sweet Signal of Sugar in Space, American Association for the Advancement of Science, retrieved 2006-12-20 
  148. ^ Loomis, R. A.; et al. (2013), "The Detection of Interstellar Ethanimine CH3CHNH) from Observations Taken during the GBT PRIMOS Survey", Astrophysical Journal Letters 765: L9,  
  149. ^ Guelin, M.; et al. (1997), "Detection of a new linear carbon chain radical: C7H", Astronomy and Astrophysics 317: L37–L40,  
  150. ^ Belloche, A.; et al. (2008), "Detection of amino acetonitrile in Sgr B2(N)", Astronomy & Astrophysics 482: 179–196,  
  151. ^ Remijan, Anthony J.; et al. (2014), CO]"2"OBSERVATIONAL RESULTS OF A MULTI-TELESCOPE CAMPAIGN IN SEARCH OF INTERSTELLAR UREA [(NH2), Astrophysical Journal 783 (2): 77,  
  152. ^ a b Remijan, Anthony J.; et al. (2006), "Methyltriacetylene (CH3C6H) toward TMC-1: The Largest Detected Symmetric Top", Astrophysical Journal 643 (1): L37–L40,  
  153. ^ Snyder, L. E.; et al. (1974), "Radio Detection of Interstellar Dimethyl Ether", Astrophysical Journal 191: L79–L82,  
  154. ^ Zuckerman, B.; et al. (1975), "Detection of interstellar trans-ethyl alcohol", Astrophysical Journal 196 (2): L99–L102,  
  155. ^ Cernicharo, J.; Guelin, M. (1996), "Discovery of the C8H radical", Astronomy and Astrophysics 309: L26–L30,  
  156. ^ Brünken, S.; et al. (2007), "Detection of the Carbon Chain Negative Ion C8H in TMC-1", Astrophysical Journal 664 (1): L43–L46,  
  157. ^ a b c d Bell, M. B.; et al. (1997), "Detection of HC11N in the Cold Dust Cloud TMC-1", Astrophysical Journal Letters 483 (1): L61–L64,  
  158. ^ Kroto, H. W.; et al. (1978), "The detection of cyanohexatriyne, H (C≡ C)3CN, in Heiles's cloud 2", The Astrophysical Journal 219: L133–L137,  
  159. ^ Marcelino, N.; et al. (2007), "Discovery of Interstellar Propylene (CH2CHCH3): Missing Links in Interstellar Gas-Phase Chemistry", Astrophysical Journal 665 (2): L127–L130,  
  160. ^ Kolesniková, L.; et al. (2014), "Spectroscopic Characterization and Detection of Ethyl Mercaptan in Orion", Astrophysical Journal Letters 784 (1): L7,  
  161. ^ Snyder, Lewis E.; et al. (2002), "Confirmation of Interstellar Acetone", The Astrophysical Journal 578 (1): 245–255,  
  162. ^ Hollis, J. M.; et al. (2002), "Interstellar Antifreeze: Ethylene Glycol", Astrophysical Journal 571 (1): L59–L62,  
  163. ^ Hollis, J. M. (2005), "Complex Molecules and the GBT: Is Isomerism the Key?" (PDF), Complex Molecules and the GBT: Is Isomerism the Key?, Proceedings of the IAU Symposium 231, Astrochemistry throughout the Universe,  
  164. ^ Eyre, Michael (26 September 2014). "Complex organic molecule found in interstellar space". BBC News. Retrieved 2014-09-26. 
  165. ^ Belloche, Arnaud; Garrod, Robin T.; Müller, Holger S. P.; Menten, Karl M. (26 September 2014). "Detection of a branched alkyl molecule in the interstellar medium: iso-propyl cyanide". Science 345 (6204): 1584–1587.  
  166. ^ a b Belloche, A.; et al. (May 2009), "Increased complexity in interstellar chemistry: Detection and chemical modeling of ethyl formate and n-propyl cyanide in Sgr B2(N)", Astronomy and Astrophysics 499 (1): 215–232,  
  167. ^ Tercero, B.; et al. (2013), "Discovery of Methyl Acetate and Gauche Ethyl Formate in Orion", Astrophysical Journal Letters 770: L13,  
  168. ^ a b Cami, Jan; et al. (July 22, 2010), "Detection of C60 and C70 in a Young Planetary Nebula", Science 329 (5996): 1180–2,  
  169. ^ Foing, B. H.; Ehrenfreund, P. (1994), "Detection of two interstellar absorption bands coincident with spectral features of C60+", Nature 369 (6478): 296–298,  
  170. ^ Berné, Olivier; Mulas, Giacomo; Joblin, Christine (2013), "Interstellar C60+",  
  171. ^ a b Lacour, S.; et al. (2005), "Deuterated molecular hydrogen in the Galactic ISM. New observations along seven translucent sightlines", Astronomy and Astrophysics 430 (3): 967–977,  
  172. ^ a b c d Ceccarelli, Cecilia (2002), "Millimeter and infrared observations of deuterated molecules", Planetary and Space Science 50 (12–13): 1267–1273,  
  173. ^ Green, Sheldon (1989), "Collisional excitation of interstellar molecules - Deuterated water, HDO", Astrophysical Journal Supplement Series 70: 813–831,  
  174. ^ Butner, H. M.; et al. (2007), "Discovery of interstellar heavy water", Astrophysical Journal 659 (2): L137–L140,  
  175. ^ a b c d Turner, B. E.; Zuckerman, B. (1978), "Observations of strongly deuterated molecules - Implications for interstellar chemistry", Astrophysical Journal, Part 2 - Letters to the Editor 225: L75–L79,  
  176. ^ Lis, D. C.; et al. (2002), "Detection of Triply Deuterated Ammonia in the Barnard 1 Cloud", Astrophysical Journal 571 (1): L55–L58,  
  177. ^ Hatchell, J. (2003), "High NH2D/NH3 ratios in protostellar cores", Astronomy and Astrophysics 403 (2): L25–L28,  
  178. ^ Turner, B. E. (1990), "Detection of doubly deuterated interstellar formaldehyde (D2CO) - an indicator of active grain surface chemistry", Astrophysical Journal, Part 2 - Letters 362: L29–L33,  
  179. ^ Cernicharo, J.; et al. (2013), "Detection of the Ammonium ion in space", Astrophysical Journal Letters 771: L10,  
  180. ^ Doménech, J. L.; et al. (2013), "Improved Determinination of the 10-00 Rotational Frequency of NH3D+ from the High-Resolution Spectrum of the ν4 Infrared Band", Astrophysical Journal Letters 771: L11,  
  181. ^ Gerin, M.; et al. (1992), "Interstellar detection of deuterated methyl acetylene", Astronomy and Astrophysics 253 (2): L29–L32,  
  182. ^ Markwick, A. J.; Charnley, S. B.; Butner, H. M.; Millar, T. J. (2005), "Interstellar CH3CCD", The Astrophysical Journal 627 (2): L117–L120,  
  183. ^ Agúndez, M.; et al. (2008-06-04), "Tentative detection of phosphine in IRC +10216", Astronomy & Astrophysics 485 (3): L33,  
  184. ^ Gupta, H.; et al. (2013), "Laboratory Measurements and Tentative Astronomical Identification of H2NCO+", Astrophysical Journal Letters 778: L1,  
  185. ^ Kuan, Y. J.; et al. (2003), "Interstellar Glycine", Astrophysical Journal 593 (2): 848–867,  
  186. ^ Widicus Weaver, S. L.; Blake, G. A. (2005), "1,3-Dihydroxyacetone in Sagittarius B2(N-LMH): The First Interstellar Ketose", Astrophysical Journal Letters 624 (1): L33–L36,  
  187. ^ Fuchs, G. W.; et al. (2005), "Trans-Ethyl Methyl Ether in Space: A new Look at a Complex Molecule in Selected Hot Core Regions", Astronomy & Astrophysics 444 (2): 521–530,  
  188. ^ Iglesias-Groth, S.; et al. (2008-09-20), "Evidence for the Naphthalene Cation in a Region of the Interstellar Medium with Anomalous Microwave Emission", The Astrophysical Journal Letters 685: L55–L58,   - This spectral assignment has not been independently confirmed, and is described by the authors as "tentative" (page L58).
  189. ^ García-Hernández, D. A.; et al. (2011), Detections in Magellanic Cloud Planetary Nebulae"24, and (Possible) Planar C70, C60"The Formation of Fullerenes: Clues from New C, Astrophysical Journal Letters 737 (2): L30,  
  190. ^ Iglesias-Groth, S.; et al. (May 2010), "A search for interstellar anthracene toward the Perseus anomalous microwave emission region", Monthly Notices of the Royal Astronomical Society 407 (4): 2157–2165,  


See also

Atoms Molecule Designation
2 SiH Silylidine[82]
4 PH3 Phosphine[183]
4 MgCCH Magnesium monoacetylide[140]
4 NCCP Cyanophosphaethyne[140]
5 C5 Linear C5[39]
5 H2NCO+ -[184]
4 SiH3CN Silyl cyanide[140]
10 H2NH2CCOOH Glycine[43][185]
12 CO(CH2OH)2 Dihydroxyacetone[186]
12 C2H5OCH3 Ethyl methyl ether[187]
18 C10H8+ Naphthalene cation[188]
24 C24 Graphene[189]
24 C14H10 Anthracene[10][190]
26 C16H10 Pyrene[10]

Evidence for the existence of the following molecules has been reported in scientific literature, but the detections are either described as tentative by the authors, or have been challenged by other researchers. They await independent confirmation.

Unconfirmed (13)

Atoms Molecule Designation
2 HD Hydrogen deuteride[171][172]
3 H2D+, HD2+ Trihydrogen cation[171][172]
3 HDO, D2O Heavy water[173][174]
3 DCN Hydrogen cyanide[175]
3 DCO Formyl radical[175]
3 DNC Hydrogen isocyanide[175]
3 N2D+ [175] 
4 NH2D, NHD2, ND3 Ammonia[172][176][177]
4 HDCO, D2CO Formaldehyde[172][178]
5 NH3D+ Ammonium ion[179][180]
7 CH2DCCH, CH3CCD Methylacetylene[181][182]

These molecules all contain one or more deuterium atoms, a heavier isotope of hydrogen.

Deuterated molecules (17)

Atoms Molecule Designation Mass Ions
10 (CH3)2CO Acetone[94][161] 58
10 (CH2OH)2 Ethylene glycol[162][163] 62
10 CH3CH2CHO Propanal[121] 58
10 CH3C5N Methyl-cyano-diacetylene[121] 89
10 (CH3)2CHCN Isopropyl cyanide[164][165] 69
11 HC8CN Cyanotetra-acetylene[32][157] 123
11 C2H5OCHO Ethyl formate[166] 74
11 CH3COOCH3 Methyl acetate[167] 74
11 CH3C6H Methyltriacetylene[121][152] 88
12 C6H6 Benzene[137] 78
12 C3H7CN n-Propyl cyanide[166] 69
13 HC10CN Cyanodecapentayne[157] 147
13 HC11N Cyanopentaacetylene[157] 159
60 C60 Buckminsterfullerene
(C60 fullerene)
720 C60+[169][170]
70 C70 C70 fullerene[168] 840

Ten or more atoms (15)

Diacetylene, HCCCCH
Methyldiacetylene, HCCCCCH3
Cyanotetraacetylene, HCCCCCCCCCN
A number of polyyne-derived chemicals are among the heaviest molecules found in the interstellar medium.
Molecule Designation Mass Ions
CH3C4H Methyldiacetylene[152] 64
CH3OCH3 Dimethyl Ether[153] 46
CH3CH2CN Propionitrile[32][94][122][135] 55
CH3CONH2 Acetamide[121][132] 59
CH3CH2OH Ethyl Alcohol[154] 46
C8H Octatetraynyl radical[155] 97 C8H[156]
HC7N Cyanohexatriyne or Cyanotriacetylene[32][114][157][158] 99
CH3CHCH2 Propylene (propene)[159] 42
CH3CH2SH Ethyl mercaptan[160] 62

Nine atoms (10)

Molecule Designation Mass
H3CC2CN Methylcyanoacetylene[146] 65
H2COHCHO Glycolaldehyde[147] 60
HCOOCH3 Methyl formate[94][122][147] 60
CH3COOH Acetic acid[145] 60
H2C6 Hexapentaenylidene[32][137] 74
CH2CHCHO Propenal[121] 56
CH2CCHCN Cyanoallene[121][146] 65
CH3CHNH Ethanimine[148] 43
C7H Heptatrienyl radical[149] 85
NH2CH2CN Aminoacetonitrile[150] 56
(NH2)2CO Urea[151] 60

Eight atoms (11)

The radio signature of acetic acid, a compound found in vinegar, was confirmed in 1997.[145]
Molecule Designation Mass Ions
c-C2H4O Ethylene oxide[142] 44
CH3C2H Methylacetylene[43] 40
H3CNH2 Methylamine[143] 31
CH2CHCN Acrylonitrile[94][135] 53
H2CHCOH Vinyl alcohol[141] 44
C6H Hexatriynyl radical[32][73] 73 C6H[122][144]
HC4CN Cyanodiacetylene[94][127][135] 75
CH3CHO Acetaldehyde[32][142] 44

Seven atoms (9)

Acetaldehyde (above) and its isomers vinyl alcohol and ethylene oxide have all been detected in interstellar space.[141]
Molecule Designation Mass Ions
c-H2C3O Cyclopropenone[132] 54
E-HNCHCN E-Cyanomethanimine[133] 54
C2H4 Ethylene[134] 28
CH3CN Acetonitrile[94][135][136] 40
CH3NC Methyl isocyanide[135] 40
CH3OH Methanol[94] 32
CH3SH Methanethiol[113] 48
l-H2C4 Diacetylene[32][137] 50
Protonated cyanoacetylene 52 HC3NH+[84]
HCONH2 Formamide[132] 44
C5H Pentynylidyne[32][73] 61
C5N Cyanobutadiynyl radical[138] 74
HC2CHO Propynal[139] 54
HC4N [32]  63
CH2CNH Ketenimine[121] 40
C5S [140] 92

Six atoms (16)

In the ISM, formamide (above) can combine with methylene to form acetamide.[132]
Molecule Designation Mass Ions
Ammonium Ion[118][119]  18 NH4+
CH4 Methane[56] 16
CH3O Methoxy radical[120] 31
c-C3H2 Cyclopropenylidene[43][121][122] 38
l-H2C3 Propadienylidene[122] 38
H2CCN Cyanomethyl 40
H2C2O Ketene[94] 42
H2CNH Methylenimine[123] 29
HNCNH Carbodiimide[124] 42
Protonated formaldehyde 31 H2COH+[125]
C4H Butadiynyl[32] 49 C4H[126]
HC3N Cyanoacetylene[32][43][84][122][127] 51
HCC-NC Isocyanoacetylene[128] 51
HCOOH Formic acid[122] 46
NH2CN Cyanamide[129] 42
HC(O)CN Cyanoformaldehyde[130] 55
SiC4 Silicon-carbide cluster[67] 92
SiH4 Silane[131] 32

Five atoms (18)

Methane, the primary component of natural gas, has also been detected on comets and in the atmosphere of several planets in the Solar System.[117]
Molecule Designation Mass Ions
CH3 Methyl radical[99] 15
l-C3H Propynylidyne[32][100] 37 l-C3H+[101]
c-C3H Cyclopropynylidyne[102] 37
C3N Cyanoethynyl[38] 50 C3N[74]
C3O Tricarbon monoxide[100] 52
C3S Tricarbon sulfide[32][73] 68
Hydronium 19 H3O+[103]
C2H2 Acetylene[104] 26
H2CN Methylene amidogen[105] 28 H2CN+[42]
H2CO Formaldehyde[98] 30
H2CS Thioformaldehyde[106] 46
HCCN [107] 39
HCCO Ketenyl[108] 41
Protonated hydrogen cyanide 28 HCNH+[84]
Protonated carbon dioxide 45 HOCO+[109]
HCNO Fulminic acid[110] 43
HOCN Cyanic acid[111] 43
HOOH Hydrogen peroxide[112] 34
HNCO Isocyanic acid[94] 43
HNCS Isothiocyanic acid[113] 59
NH3 Ammonia[32][114] 17
HSCN Thiocyanic acid[115] 59
SiC3 Silicon tricarbide[32]  64
HMgNC Hydromagnesium isocyanide[116]  51.3

Four atoms (27)

Molecule Designation Mass Ions
AlNC Aluminium isocyanide[32] 53
AlOH Aluminium hydroxide[70] 44
C3 Tricarbon[39] 36
C2H Ethynyl radical[32][43] 25
CCN Cyanomethylidyne[71] 38
C2O Dicarbon monoxide[72] 40
C2S Thioxoethenylidene[73] 56
C2P [74] 55
CO2 Carbon dioxide[75] 44
FeCN Iron cyanide[76] 82
Protonated molecular hydrogen 3 H3+[2][69]
H2C Methylene radical[38] 14
Chloronium 37.5 H2Cl+[77]
H2O Water[78] 18 H2O+[79]
HO2 Hydroperoxyl[80] 33
H2S Hydrogen sulfide[32] 34
HCN Hydrogen cyanide[32][43][81] 27
HNC Hydrogen isocyanide[82] 27
HCO Formyl radical[83] 29 HCO+[42][83][84]
HCP Phosphaethyne[85] 44
Thioformyl 45 HCS+[42][84]
HNC Hydrogen isocyanide[86] 27
Diazenylium 29 HN2+[84]
HNO Nitroxyl[87] 31
Isoformyl 29 HOC+[43]
KCN Potassium cyanide[32] 65
MgCN Magnesium cyanide[32] 50
MgNC Magnesium isocyanide[32] 50
NH2 Amino radical[88] 16
29 N2H+[42][89]
N2O Nitrous oxide[90] 44
NaCN Sodium cyanide[32] 49
NaOH Sodium hydroxide[91] 40
OCS Carbonyl sulfide[92] 60
O3 Ozone[93] 48
SO2 Sulfur dioxide[32][94] 64
c-SiC2 c-Silicon dicarbide[32][67] 52
SiCSi Disilicon carbide[95] 68
SiCN Silicon carbonitride[96] 54
SiNC [97] 54
TiO2 Titanium dioxide[68] 79.9

Triatomic (43)

The H3+ cation is one of the most abundant ions in the universe. It was first detected in 1993.[2][69]
Molecule Designation Mass Ions
AlCl Aluminium monochloride[32][33] 62.5
AlF Aluminium monofluoride[32][34] 46
AlO Aluminium monoxide[35] 43
Argon hydride[36][37] 41 ArH+
C2 Diatomic carbon[38][39] 24
Fluoromethylidynium 31 CF+[40]
CH Methylidyne radical[41] 13 CH+[42]
CN Cyanogen radical[32][41][43][44] 26 CN+,[45] CN[46]
CO Carbon monoxide[32][47][48] 28 CO+[49]
CP Carbon monophosphide[44] 43
CS Carbon monosulfide[32] 44
FeO Iron(II) oxide[50] 82
H2 Molecular hydrogen[51] 2
HCl Hydrogen chloride[52] 36.5 HCl+[53]
HF Hydrogen fluoride[54] 20
HO Hydroxyl radical[32] 17 OH+[55]
KCl Potassium chloride[32][33] 75.5
NH Nitrogen monohydride[56][57] 15
N2 Molecular nitrogen[58][59] 28
NO Nitric oxide[60] 30 NO+[45]
NS Nitrogen sulfide[32] 46
NaCl Sodium chloride[32][33] 58.5
Magnesium monohydride cation 25.3 MgH+[45]
NaI Sodium iodide[61] 150
O2 Molecular oxygen[62] 32
PN Phosphorus mononitride[63] 45
PO Phosphorus monoxide[64] 47
SH Sulfur monohydride[65] 33 SH+[66]
SO Sulfur monoxide[32] 48 SO+[42]
SiC Carborundum[32][67] 40
SiN Silicon mononitride[32] 42
SiO Silicon monoxide[32] 44
SiS Silicon monosulfide[32] 60
TiO Titanium oxide[68] 63.9

Diatomic (43)

Carbon monoxide is frequently used to trace the distribution of mass in molecular clouds.[31]

[30] Larger molecules have so far all had at least one carbon atom, with no N-N or O-O bonds.[30] Most of the molecules detected so far are

The following tables list molecules that have been detected in the interstellar medium, grouped by the number of component atoms. If there is no entry in the Molecule column, only the ionized form has been detected. For molecules where no designation was given in the scientific literature, that field is left empty. Mass is given in Atomic mass units. The total number of unique species, including distinct ionization states, is listed in parentheses in each section header.


In March 2015, NASA scientists reported that, for the first time, complex life, including uracil, cytosine and thymine, have been formed in the laboratory under outer space conditions, using starting chemicals, such as pyrimidine, found in meteorites. Pyrimidine, like polycyclic aromatic hydrocarbons (PAHs), the most carbon-rich chemical found in the Universe, may have been formed in red giants or in interstellar dust and gas clouds, according to the scientists.[29]

A particularly large and rich region for detecting interstellar molecules is Sagittarius B2 (Sgr B2). This giant molecular cloud lies near the center of the Milky Way galaxy and is a frequent target for new searches. About half of the molecules listed below were first found near Sgr B2, and nearly every other molecule has since been detected in this feature.[27] A rich source of investigation for circumstellar molecules is the relatively nearby star CW Leonis (IRC +10216), where about 50 compounds have been identified.[28]

In 2013, Dwayne Heard at the University of Leeds suggested[26] that quantum mechanical tunneling could explain a reaction his group observed taking place, at a significantly higher than expected rate, between cold (around 63 Kelvin) hydroxyl and methanol molecules, apparently bypassing intramolecular energy barriers which would have to be overcome by thermal energy or ionization events for the same rate to exist at warmer temperatures. The proposed tunneling mechanism may help explain the common observation of fairly complex molecules (up to tens of atoms) in interstellar space.

PAHs are found everywhere in deep space[24] and, in June 2013, PAHs were detected in the upper atmosphere of Titan, the largest moon of the planet Saturn.[25]

In September 2012, amino acids and nucleotides, the raw materials of proteins and DNA, respectively".[22][23] Further, as a result of these transformations, the PAHs lose their spectroscopic signature which could be one of the reasons "for the lack of PAH detection in interstellar ice grains, particularly the outer regions of cold, dense clouds or the upper molecular layers of protoplanetary disks."[22][23]

[21] In August 2012, astronomers at

In October 2011, scientists found using [14]

In 2010, fullerenes (or "buckyballs") were detected in nebulae.[12] Fullerenes have been implicated in the origin of life; according to astronomer Letizia Stanghellini, "It's possible that buckyballs from outer space provided seeds for life on Earth."[13]

In 2004, scientists reported[10] detecting the spectral signatures of anthracene and pyrene in the ultraviolet light emitted by the Red Rectangle nebula (no other such complex molecules had ever been found before in outer space). This discovery was considered a confirmation of a hypothesis that as nebulae of the same type as the Red Rectangle approach the ends of their lives, convection currents cause carbon and hydrogen in the nebulae's core to get caught in stellar winds, and radiate outward.[11] As they cool, the atoms supposedly bond to each other in various ways and eventually form particles of a million or more atoms. The scientists inferred[10] that since they discovered polycyclic aromatic hydrocarbons (PAHs) — which may have been vital in the formation of early life on Earth — in a nebula, by necessity they must originate in nebulae.[11]

thus demonstrating the existence of polycyclic aromatic hydrocarbon molecules in space. [9] later proposed the identification of bicyclic aromatic compounds from an analysis of the ultraviolet extinction absorption at 2175A.,Chandra Wickramasinghe and Fred Hoyle [8]CO).2 (Hformaldehyde proposed the existence of polymeric composition based on the molecule Chandra Wickramasinghe probably polymers. [7]

This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from World eBook Library are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.