a work in progress
(recently added species are highlighted)

LISTS OF INTERSTELLAR & CIRCUMSTELLAR MOLECULES:
NIST Table of Species (Microwave Detections)
The Cosmic Ice Laboratory at NASA Goddard Space Flight Center
National Radio Astronomy Observatory Observatoire de Paris
Harvard-Smithsonian Center for Astrophysics Cologne Database
Chalmers University of Technolology Open Encylopedia
The Encyclopedia of Astrobiology, Astronomy, and Spaceflight
NOTES: (1) Molecules are ordered by first year of reported discovery, though
some identifications required confirmation by later observations. (2) Identifications
explicitly considered to be tentative are indicated with italics; recent detections
are implicitly tentative. (3)Detections currently under dispute are indicated with
an asterisk and orange text.


YEAR
SPECIES
CITATION
SOURCE AND LINES
1937 CH Considerations Regarding Interstellar Molecules
P. Swings and L. Rosenfeld, ApJ 86:483-486 (1937)
Evidence for the Molecular Origin of Some Hitherto Unidentified Interstellar Lines
A. McKellar, Publ Astron Soc Pac 52:187-192 (1940)
Some Results with the COUDÉ Spectrograph of the Mount Wilson Observatory
W. S. Adams, ApJ 93:11-23 (1941)
Ophiuchi
lines at 3878.8, 3886.4, 3890.2,
& 4300.3
1940 CN Evidence for the Molecular Origin of Some Hitherto Unidentified Interstellar Lines
A. McKellar, Publ Astron Soc Pac 52:187-192 (1940)
Some Results with the COUDÉ Spectrograph of the Mount Wilson Observatory
W. S. Adams, ApJ 93:11-23 (1941)
Ophiuchi
lines at 3874.02 & 3874.61
1941 CH+ Note on CH+ in Interstellar Space and in the Laboratory"
A. E. Douglas and G.Herzberg, ApJ 94:381 (1941)
???
lines at 4232.6, 3957.7, & 3745.3
1963 OH Radio Observations of OH in the Interstellar Medium
S. Weinreb, A. H. Barrett, M. L. Meeks, and J. C. Henry, Nature 200:829-831 (1963)
galactic center
???
1968 NH3 Detection of NH3 Molecules in the Interstellar Medium by Their Microwave Emission
A. C. Cheung, D. M. Rank, C. H. Townes, D. D. Thornton, and W. J. Welch, Phys Rev Lett 25:1701-1705 (1968)
galactic center
???
1969 H2O Delection of Water in Interstellar Regions by its Microwave Radiation
A. C. Cheung, D. M. Rank, C. H. Townes, D. D. Thornton, and W. J. Welch, Nature 221:626 (1969)
???
???
1969 H2CO Microwave Detection of Interstellar Formaldehyde
L. E. Synder, D. Buhl, B. Zuckerman, and P. Palmer, Phys Rev Lett 22:679 (1969)
Numerous sources
111-110 (4830 MHz)
1970 HCO+ Unidentified Interstellar Microwave Line
D. Buhl and L. E. Synder, Nature 228:267 (1970)
???
J=1-0 (89.19 GHz)
1970 H2 Rocket Observation of Interstellar Molecular Hydrogen
G. R. Carruthers, ApJ 161:L81-L85 (1970)
Persei
lines from the Lyman series
for (B 1u X 1g)
1971 CO
ASTROMOLECULE OF THE MONTH FOR JUN 2003
Observation of CO Emission at 2.6 Millimeters from IRC+10216
P. Solomon, K. B. Jefferts, A. A.Penzias, and R. W. Wilson, ApJ 163:L53-L56 (1971)
Carbon Monoxide in the Interstellar Spectrum of Zeta Ophiuchi
A. M. Smith and T. P. Stecher, ApJ 164:L43-L47 (1971)
IRC+10216
1-0 (115271.2 MHz)

Ophiuchi
Eight UV-vis transitions in the
( A 1 X 1+ ) fourth positive system
1971 HC3N Detection of Interstellar Cyanoacetylene
B. E. Turner, ApJ 163:L35-L39 (1971)
Detection of Formic Acid in Sagittarius B2 by its 2(11)-2(12) Transition
G. Winnewisser and E. Churchwell, ApJ 200:L33-L36 (1975)
Sgr B2
J = 0 1 features (9097.7 MHz)
1971 HCN Observations of Radio Emission from Interstellar Hydrogen Cyanide
L. E. Snyder and D. Buhl, ApJ 163:L47-L52 (1971)
W3(OH), Orion A, and 4 other sources
J = 1-0 (88.6 GHz)
1971 HCOOH
ASTROMOLECULE OF THE MONTH FOR MAY 2004
Microwave Detection of Interstellar Formic Acid
B. Zuckerman, J. A. Ball, and C. A. Gottlied, ApJ 163:L41-L45 (1971)
Detection of Formic Acid in Sagittarius B2 by its 2(11)-2(12) Transition
G. Winnewisser and E. Churchwell, ApJ 200:L33-L36 (1975)
Sgr B2
211-212 (4916 MHz)
1971 SiO Discovery of Interstellar Silicon Monoxide
R. W. Wilson, A. A. Penzias, K. B. Jefferts, N. Kutner, and P. Thaddeus, ApJ 167:L97-L100 (1971)
Detection of Silicon Monoxide at 87 GHz
D. F. Dickinson, ApJ 175:L43-L46 (1972)
Sgr B2, Orion A
2-1 (86847 MHz)
3-2 (130246 MHz)
1971 CS Interstellar Carbon Monosulfide
A. A. Penzias, P. M. Solomon, R. W. Wilson, A. A. Penzias, and K. B. Jefferts, ApJ 168:L53-L58 (1971)
Observations of CS, HCN, U89.2, and U90.7 in NGC 2264
B. Zuckerman, M. Morris, P. Palmer, and B. E. Turner, ApJ 173:L125-L129 (1972)
Orion A, W51, IRC+10216, DR 21
3-2 (146969.16 MHz)
NGC2264
2-1 (??? MHz)
1971 OCS Detection of Interstellar Carbonyl Sulfide
K. B. Jefferts, A. A. Penzias, P. M. Solomon, and P. M. Solomon, ApJ 168:L111-L113 (1971)
Sgr B2
9-8 (109462.8 MHz)
1971 NH2CHO
ASTROMOLECULE OF THE MONTH FOR JAN 2005
Microwave Detection of Interstellar Formamide
R. H. Rubin, G. W. Swenson, Jr., R. C. Solomon, and H. L. Flygare, ApJ 169:L39-L44 (1971)
Sgr B2
211-212 (4620 MHz)
1972 H2S Interstellar Hydrogen Sulfide
P. Thaddeus, M. L. Kutner, A. A. Penzias, R. W. Wilson, and K. B. Jefferts, ApJ 176:L73-L76 (1972)
7 sources
110-101 (168.7 GHz)
1972 HNCO
ASTROMOLECULE OF THE MONTH FOR APR 2004
Interstellar Isocyanic Acid
L. E. Snyder and D. Buhl, ApJ 177:619-623 (1972)
Sgr B2
404-303 (87925 MHz)
101-000 (21982 MHz)
1973 CH3CHO Detection of Acetaldehyde in Sagittarius
C. A. Gottlieb, Molecules in the Galactic Environment (eds. M. A. Gordon and L. E. Snyder), Wiley-Interscience, New York, 181-185 (1973)
Microwave Emission of the 2(11) -> 2(12) Rotational Transition in Interstellar Acetaldehyde
N. Fourikis, M. W. Sinclair, B. J. Robinson, P. D. Godfrey, and R. D. Brown, Aust J Phys 27:425-430 (1974)
Observation of the 6(16)-5(15) Transitions of acetaldehyde in Sagittarius B2
W. Gilmore, M. Morris, P. Palmer, D. R. Johnson, F. J. Lovas, B. E. Turner, and B. Zuckerman, ApJ 204:43-46 (1976)
Sgr B2
110-111 (1065 MHz)
211-212 (3195 MHz)
616-515 (112250 MHz)
1973 CH2NH Discovery of Interstellar Methanimine (Formaldimine)
P. D. Godfrey, R. D. Brown, B. J. Robinson, and M. W. Sinclair, Astrophys Lett 13:119 (1973)
???
???
1973 H2CS Detection of Interstellar Thioformaldehyde
M. W. Sinclair, N. Fourikis, J. C. Ribes, B. J. Robinson, R. D. Brown, and P. D. Godfrey, Aust J Phys 26:85-91 (1973)
Sgr B2
211-212 (3139.38 MHz)
1973 HNC Radio Astronomy - Interstellar Methylacetylene and Isocyanic Acid
L. E. Snyder and D. Buhl, Nature Phys Sci 243:45 (1973)
Sgr B2
J = 1-0 (90665.0 MHz)
1973 SO Interstellar Sulfur Monoxide
C. A. Gottlieb and J. Ball, ApJ 184:L59-L64 (1973)
Orion A, etc.
32-21 (99295.85 MHz)
43-32 (138178.60 MHz)
1974 CH3OCH3 Radio Detection of Interstellar Dimethyl Ether
L. E. Snyder, D. Buhl, P. R. Schwartz, F. O. Clark, D. R. Johnson, F. J. Lovas and P. T. Giguere, ApJ 191:L79-L82 (1974)
Orion Nebula
606 515 (90.9 GHz)
220 211 (86.2 GHz)
211 202 (31.1 GHz)
1974 CH3NH2 Detection of Interstellar Methylamine
N. Kaifu, M. Morimoto, K. Nagane, K. Akabane, T. Iguchi, and K. Takagi, ApJ 191:L135-L137 (1974)
Detection of Interstellar Methylamine by its 2(02)->1(10) A(a) State Transition
N. Fourikis, K. Takagi, and M. Morimoto, ApJ 191:L139-L141 (1974)
Sgr B2, Orion A
515-505 (73.0 GHz)
414-404 (86.1 GHz)
202-110 (3.5 cm)
1974 N2H+ U93.174 - A New Interstellar Line with Quadrupole Hyperfine Splitting
B. E. Turner, ApJ 193:L83-L87 (1974)
Tentative Identification of U93.174 as the Molecular Ion N2H+
S. Green, J. A. Montgomery, Jr., and P. Thaddeus, ApJ 193:L89-L91 (1974)
many sources
J = 1 0 triplet (93.174 GHz)
1974 C2H The Ethynyl Radical C2H - A New Interstellar Molecule
K. D. Tucker, M. L. Cuttner, and P. Thaddeus, ApJ 193:L115-L119 (1974)
Orion A, etc.
(3/2,2)-(1/2,1) (87284.4 MHz)
(3/2,1)-(1/2,0) (87317.1 MHz)
(1/2,1)-(1/2,1) (87328.7 MHz)
(1/2,0)-(1/2,1) (87402.1 MHz)
1975 CH3CH2OH Detection of Interstellar trans-Ethyl Alcohol
B. Zuckerman, B. E. Turner, D. R. Johnson, F. J. Lovas, N. Fourikis, P. Palmer, M. Morris, A. E. Lilley, J. A. Ball, and F. O. Clark, ApJ 196:L99-L102 (1975)
Sgr B2
606-515 (85265.46 MHz)
414-303 (90117.51 MHz)
515-440 (104808.58 MHz)
1975 HCOOCH3
ASTROMOLECULE OF THE MONTH FOR SEP 2004
Discovery of Interstellar Methyl Formate
R. D. Brown, J. G. Crofts, P. D. Godfrey, F. F. Gardner, B. J. Robinson, and J. B. Whiteoak, ApJ 197:L29-L31 (1975)
Observations of Methyl Formate in the Galactic Center
E. Churchwell and G. Winnewisser, A&A 45:229-231 (1975)
Sgr B2
A: 110-111 (1610.249 MHz)
E: 110-111 (1610.906 MHz)
1975 SO2
ASTROMOLECULE OF THE MONTH FOR AUG 2003
Radio Detection of Interstellar Sulfur Dioxide
L. E. Snyder, J. M. Hollis, B. L. Ulich, F. J. Lovas, D. R. Johnson, and D. Buhl, ApJ 198:L81-L84 (1975)
Orion A
817-808 (83688.074 MHz)
835-928 (86639.100 MHz)
735-826 (97702.352 MHz)
1975 HDO Microwave Detection of Interstellar HDO
B. E. Turner, B. Zuckerman, N. Fourikis, M. Morris, and P. Palmer, ApJ 198:L125-L128 (1975)
Orion KL
111-110 (3.72 nm)
1975 SiS
ASTROMOLECULE OF THE MONTH FOR JUL 2004
Detection of Interstellar SiS and a Study of the IRC+10216 Molecular Envelope
M. Morris, W. Gilmore, P. Palmer, B. E. Turner, and B. Zuckerman, ApJ 199:L47-L51 (1975)
IRC+10216
5-4 (90771.85 MHz)
6-5 (108924.64 MHz)
1975 NS Detection of Interstellar Nitrogen Sulfide
C. A. Gottlieb, J. A. Ball, E. W. Gottlieb, C. J. Lada, and H. Penfield, ApJ 200:L147-L149 (1975)
Detection of 2.6-millimeter Radiation Probably Due to Nitrogen Sulfide
T. B. H. Kuiper, R. K. Kakar, E. N. Rodriguez Kuiper, and B. Zuckerman, ApJ 200:L151-L143 (1975)
Sgr B2
21/2 J=5/2-3/2 c-state (115.16 GHz)
21/2 J=5/2-3/2 d-state (115.6 GHz)
1975 NH2CN Microwave Detection of Interstellar Cyanamide
B. E. Turner, H. S. Liszt, N. Kaifu, and A. G. Kisliakov, ApJ 201:L149-L:152 (1975)
Sgr B2
413-312 (80504.5 MHz)
514-413 (100629.5 GHz)
1976 HCO Radio Detection of the Interstellar Formyl Radical
L. E. Snyder, J. M. Hollis, and B. L. Ulich, ApJ 208:L91-L94 (1976)
W3, NGC 2024, W51, K3-50
101-000, J=3/2-1/2, F=2-1 (86670.65 MHz)
1977 C2 Detection of C2 in the interstellar spectrum of Cygnus OB2 number 12(VI Cygni Number 12)
S. P. Souza and B. L. Lutz, ApJ 216:L49-L51 (1977)
Cygnus OB2 No. 12
R- & Q-branch lines of
the (1-0) Philips band
1977 HNO Radio Detection of Nitroxyl (HNO): The First Interstellar NO Bond
B. L. Ulich, J. M. Hollis, and L. E. Snyder, ApJ 217:L105-L107 (1977)
Interstellar HNO: Confirming the Identification
J. M. Hollis, L. E. Snyder, L. M. Ziurys, and D. McGonagle, Atoms, ions and molecules: New results in spectral line astrophysics, ASP Conf Ser 16:407 (1991)
New 3 millimeter Observations of Interstellar HNO - Reinstating a Discredited Identification
L. E. Snyder, Y.-J. Kuan, L. M. Ziurys, and J. M. Hollis, ApJ 403:L17-L20 (1993)
New Detections of Interstellar HNO at 2 and 1.2 millimeters: More N-O Bonds
L. M. Ziurys, J. M. Hollis, and L. E.; Snyder, ApJ 430:706-712 (1994)
Sgr B2, NGC 2024, etc.
101-000 (81477.49 MHz)
202-101 (162937.949 MHz)
303-202 (244364.054 MHz)
1977 CH3CH2CN Detection of Interstellar Ethyl Cyanide
D. R. Johnson, F. J. Lovas, C. A. Gottlieb, E. W. Gottlieb, M. M. Litvak, M. Guélin, and P. Thaddeus, ApJ 218:370-376 (1977)
OMC-1
24 mm wavelength lines
1978 HC7N The Detection of Cyanohexatriyne in Heiles's Cloud 2
H. W. Kroto, C. Kirby, D. R. M. Walton, L. W. Avery, N. W. Broten, J. M. MacLeod, and T. Oka, ApJ 219:L133-L137 (1978)
Observations of Interstellar HC5N and HC7N in Dark Dust Clouds
L. T. Little, G. H. MacDonald, P. W. Riley, and D. N. Matheson, MNRAS 183:45P-50P (1978)
The Detection of HC5N and HC7N in IRC+10216
G. Winnewisser and C. M. Walmsley, A&A 70:L37-L39 (1978)
Heiles 2 (& TMC2)
9-8 (10152.002 MHz)
21-20 (23687.890 MHz)
22-21 (24815.870 MHz)

IRC+10216
9-8 (23687.9 MHz)
1978 HC5N Observations of Interstellar HC5N and HC7N in Dark Dust Clouds
L. T. Little, G. H. MacDonald, P. W. Riley, and D. N. Matheson, MNRAS 183:45P-50P (1978)
The Detection of HC5N and HC7N in IRC+10216
G. Winnewisser and C. M. Walmsley, A&A 70:L37-L39 (1978)
TMC2
9-8 (23963.88 MHz)
IRC+10216
9-8 (23963.897 MHz)
1978 NO Microwave Detection of Interstellar NO
H. S. Liszt and B. E. Turner, ApJ 224:L73-L76 (1978)
Sgr B2(OH)
21/2 J=3/2-1/2 (150.2 GHz)
21/2 J=3/2-1/2 (150.5 GHz)
1981 HCS+ Three New "Nonterrestrial" Molecules
P. Thaddeus, M. Guélin, and R. A. Linke, ApJ 246:L41-L45 (1971)
Sgr B2, Orion A
2-1 (85347.90 MHz)
3-2 (128020.67 MHz)
5-4 (213360.53 MHz)
6-5 (256027.8 MHz)
1984 HOCO+
ASTROMOLECULE OF THE MONTH FOR OCT 2003
Three New "Nonterrestrial" Molecules
P. Thaddeus, M. Guélin, and R. A. Linke, ApJ 246:L41-L45 (1981)
Laboratory detection of the protonated carbon dioxide by submillimeter wave spectroscopy
M. Bogey, C. Demuynck, and J. L. Destombes, A&A 138:L11-L12 (1984)
Sgr B2, Orion A
404-303 (85530.68 MHz)
505-404 (106913.36 MHz)
606-505 (128294.89 MHz)
1983 HOC+ The [HCO+]/[HOC+] Abundance Ratio in Molecular Clouds
R. C. Woods, C. S. Gudeman, R. L. Dickman, P. F. Goldsmith, G. R. Huguenin, W. M. Irvine, Å. Hjalmarson, L.-Å. Nyman, and H. Olofsson, ApJ 270:583-588 (1983)
Confirmation of Interstellar HOC+: Reevaluating the [HCO+]/[HOC+] Abundance Ratio
L. M. Ziurys and A. J. Apponi, ApJ 455:L73-L76 (1995).
Sgr B2
J = 1 0 (89487.4 MHz)
Sgr B2(OH)
J = 2 1 (178972.0 MHz)
J = 3 2 (268451.1 MHz)
1984 c-SiC2 Identification of the SiCC Radical toward IRC +10216 - The First Molecular Ring in an Astronomical Source
P. Thaddeus, S. E. Cummins, and R. A. Linke, ApJ 283:L45-L48 (1984)
IRC +10216
404 303 (93065 MHz)
423 322 (94245 MHz)
422 321 (95579 MHz)
505 404 (115383 MHz)
606 505 (137180 MHz)
625 524 (140918 MHz)
643 542 (141751 MHz)
642 541 (141755 MHz)
725 624 (170742 MHz)
1985 C3H
ASTROMOLECULE OF THE MONTH FOR JAN 2004
Astronomical Identification of the C3H Radical
P. Thaddeus, C. A. Gottlieb, A. Hjalmarson, L. E. B. Johansson, W. M. Irvine, P. Friberg, and R. A. Linke, ApJ 294:L49-L53 (1985)
TMC-1, 21/2 ladder
3/2-1/2,2-1 (32627.255 MHz)
            1-0 (32634.344 MHz)
            2-1 (32660.608 MHz)
            1-0 (32663.330 MHz)
IRC+10216, 21/2 ladder
7/2-5/2 (76199.173 MHz)
7/2-5/2 (76204.541 MHz)
9/2-7/2 (97995.509 MHz)
9/2-7/2 (98012.014 MHz)
13/2-11/2 (141636.091 MHz)
13/2-11/2 (141709.087 MHz)
15/2-13/2 (163597.576 MHz)
IRC+10216, 23/2 ladder
9/2-7/2 (103319.538 MHz)
9/2-7/2 (103372.769 MHz)
1985 HCl Chlorine in Dense Interstellar Clouds - The Abundance of HCl in OMC-1
G. A. Blake, J Keene, and T. G. Phillips, ApJ 295:501-506 (1985)
Vibrationally Excited H2, HCl, and NO(+) in the Diffuse Clouds Toward Zeta Ophiuchi
S. R. Federman, J. A. Cardell, E. F. van Dishoeck, D. L. Lambert,and J. H. Black, ApJ 445:325-329 (1995)
OMC-1
1-0 (625.9 GHz)

Ophiuchi
C 1 - X 1 (0-0) R(0) (1290.257 Å)
1985 C3O A New Interstellar Molecule - Tricarbon Monoxide
H. E. Matthews, W. M. Irvine, P. Friberg, R. D. Brown, and P. D. Godfrey, Nature 310:125-126 (1984)
Tricarbon Monoxide in TMC-1
R. D. Brown, P. D. Godfrey, D. M. Cragg, E. H. N. Rice, W. M. Irvine, P. Friberg, H. Suzuki, M. Ohishi, N. Kaifu, and M. Morimoto, ApJ 297:302-308 (1985)
TMC-1
2-1 (19243.523 MHz)
5-4 (48108.479 MHz)
8-7 (76972.590 MHz)
9-8 (86593.685 MHz)
1985 c-C3H2 Laboratory and Astronomical Identification of Cyclopropenylidene, C3H2
P. Thaddeus, J. M. Vrtilek, and C. A. Gottlieb, ApJ 299:L63-L66 (1985)
Sgr B2, etc.
11 radio lines
1986 C6H Detection of the Interstellar C6H Radical
H. Suzuki, M. Ohishi, N. Kaifu, S.-I. Ishikawa, and T. Kasuga, Publ Astron Soc Japan 38:911-917 (1986)
Detection of a Heavy Radical in IRC+10216 - The Hexatriynyl Radical C6H?
M. Guélin, J. Cernicharo, C. Kahane, J. Gomez-Gonzalez, and C. M. Walmsley, A&A 175:L5-L8 (1987)
TMC-1
13 radio lines

IRC+10216
15 radio lines
1986 HCNH+ HCNH+: A New Interstellar Molecular Ion
L. M. Ziurys and B. E. Turner, ApJ 302:L31-L36 (1986)
Sgr B2
1-0 (74111.3 MHz)
2-1 (148221.4 MHz)
3-2 (222329.4 MHz)
1986 MgNC A New Free Radical in IRC+10216
M. Guélin, J. Cernicharo, C. Kahane, and J. Gomez-Gonzales, A&A 157:L17-L20 (1986)
Laboratory Spectroscopy of MgNC - The First Radioastronomical Identification of Mg-Bearing Molecule
K. Kawakuchi, E. Kagi, T. Hirano, S. Takano, and S. Saito, ApJ 406:L39-L42 (1993)
IRC+10216
7-6 (83538.0 MHz)
8-7 (95469.3 MHz)
9-8 (107399.8 MHz)
1986 C5H Tentative Detection of the C5H Radical
J. Cernicharo, C. Kahane, J. Gómez-González, M. Guélin, A&A 164, L1-L4 (1986)
Laboratory Detection of the C5H Radical
C. A. Gottlieb, E. W. Gottlieb, and P. Thaddeus, A&A 164:L5-L6 (1986)
IRC+10216
12 radio lines
1986 H3O+ A Search for Interstellar H3O+
A. Wootten, F. Boulanger, M. Bogey, F. Combes, P. J. Encrenaz, M. Gerin, and L. Ziurys, A&A 166:L15-L18 (1986)
An Interstellar Line Coincident with the P(2,1) Transition of Hydronium (H3O+)
J. M. Hollis, E. B. Churchwell, E. Herbst, and F. C. de Lucia, Nature 322:524-626 (1986)
Detection of Interstellar H3O+: A Confirming Line.
A. Wootten, J. G. Mangum, B. E. Turner, M. Bogey, F. Boulanger, F. Combes, P. J. Encrenaz, and M. Gerin, ApJ 390:L79-L83 (1991)
OMC1, Sgr B2/Orion KL
P(2,1) (307192.4 MHz)
OMC1, Sgr B2
(3,2)-(2,2) (364797.427 MHz)
1987 C2S Laboratory Detection and Astronomical Identification of a New Free Radical, CCS 3Sigma-
S. Saito, K. Kawaguchi, S. Yamamoto, M. Ohishi, H. Suzuki, and N. Kaifu, ApJ 317:L115-L119 (1987)
Sulfur in IRC+10216
J. Cernicharo, C. Kahane, M. Guélin, and H. Hein, A&A 181:L9-L12 (1987)
TMC-1, Sgr B2
11 radio lines

IRC+10216
12 radio lines
1987 C3S Laboratory Detection of a New Carbon-Chain Molecule C3S and Its Astronomical Identification
S. Yamamoto, S. Saito, K. Kawaguchi, N. Kaifu, and H. Suzuki, ApJ 317:L119-L121 (1987)
Sulfur in IRC+10216
J. Cernicharo, C. Kahane, M. Guélin, and H. Hein, A&A 181:L9-L12 (1987)
TMC-1
4-3 (23122.985 MHz)
7-6 (40465.017 MHz)
8-7 (46245.594 MHz)

IRC+10216
11 radio lines
1987 NaCl
ASTROMOLECULE OF THE MONTH FOR DEC 2004
Metals in IRC+10216 - Detection of NaCl, AlCl, and KCl, and Tentative Detection of AlF
J. Cernicharo and M. Guélin, A&A 183:L10-L12 (1987)
IRC+10216
7-6 (91169.7 MHz)
8-7 (104189.8 MHz)
10-9 (130223.4 MHz)
11-10 (143237.0 MHz)
12-11 (156248.6 MHz)
13-12 (169258.3 MHz)
1987 AlCl Metals in IRC+10216 - Detection of NaCl, AlCl, and KCl, and Tentative Detection of AlF
J. Cernicharo and M. Guélin, A&A 183:L10-L12 (1987)
IRC+10216
6-5 (87457.9 MHz)
7-6 (101032.4 MHz)
10-9 (145744.2 MHz)
11-10 (160311.9 MHz)
1987 KCl Metals in IRC+10216 - Detection of NaCl, AlCl, and KCl, and Tentative Detection of AlF
J. Cernicharo and M. Guélin, A&A 183:L10-L12 (1987)
IRC+10216
13-12 (99928.5 MHz)
14-13 (107611.3 MHz)
17-16 (130650.2 MHz)
19-18 (146002.1 MHz)
20-19 (153678.7 MHz)
21-20 (161349.4 MHz)
1987 AlF Metals in IRC+10216 - Detection of NaCl, AlCl, and KCl, and Tentative Detection of AlF
J. Cernicharo and M. Guélin, A&A 1832:L10-L12 (1987)
Exotic Fluoride Molecules in IRC+10216: Confirmation of AlF and Searches for MgF and CaF
L. M. Ziurys, A. J. Apponi, and T. G. Phillips, ApJ 4332:729-732 (1994)
IRC+10216
3-2 (98926.6 MHz)
4-3 (131898.0 MHz)
5-4 (164867.7 MHz)

7-6 (230793.89 MHz)
8-7 (263749.35 MHz)
10-9 (329641.64 MHz)
1987 PN
ASTROMOLECULE OF THE MONTH FOR NOV 2003
Detection of Interstellar PN - The First Identified Phosphorus Compound in the Interstellar Medium
B. E. Turner and J. Bally, ApJ 321:L75-L79 (1987)
Detection of Interstellar PN - The first Phosphorus-Bearing Species Observed in Molecular Clouds
L. M. Ziurys, ApJ 321:L81-L85 (1987)
Orion KL, W51M, Sgr B2
2-1 (93979.78 MHz)
3-2 (140967.75 MHz)
5-4 (234935.69 MHz)
6-5 (281914.13 MHz)
1988 C3 Detection of C3 in the Circumstellar Shell of IRC+10216
K. H. Hinkle, J. J. Keady, and P. F. Bernath, Science 241:1319-1322 (1988)
IRC+10216
matches to 15 lines of the P and
Q branches, 2025-2056 cm-1
1988 CH2CN Identification of the Interstellar Cyanomethyl Radical (CH2CN) in the Molecular Clouds TMC-1 and Sagittarius B2
W. M. Irvine, P. Friberg, Å. Hjalmarson, S. Ishikawa, N. Kaifu, K. Kawaguchi, S. C. Madden, H. E. Matthews, M. Ohishi, S. Saito, H. Suzuki, P. Thaddeus, B. E. Turner, S. Yamamoto, and L. M. Ziurys, ApJ 334:L107-L111 (1988)
TMC-1, Sgr B2
numerous radio lines
1988 HC2CHO A New Interstellar Polyatomic Molecule: Detection of Propynal in the Cold Cloud TMC-1
W. M. Irvine, R. D. Brown, D. M. Craig, P. Friberg, P. D. Godfrey, N. Kaifu, H. E. Matthews, M. Ohishi, H. Suzuki, and H. Takeo, ApJ 335:L89-L93 (1988)
TMC-1
202-101 (18650.3 MHz)
212-111 (18325.5 MHz)
211-110 (18978.8 MHz)
404-303 (37290.1 MHz)
1989 SiC Astonomical and Laboratory Detection of the SiC Radical
J. Cernicharo, C. A. Gottlieb, M. Guélin, P. Thaddeus, P. and J. M. Vrtilek, ApJ 341:L25-L28 (1989)
IRC+10216
J′-J=2-1, Ω=1,&Lambda=e (80988 MHz)
J′-J=2-1, Ω=1,&Lambda=f (81062 MHz)
J′-J=2-1, Ω=0,&Lambda=e (83842 MHz)
J′-J=4-3, Ω=2,&Lambda=e,f (157494 MHz)
J′-J=4-3, Ω=1,&Lambda=e (161977 MHz)
J′-J=4-3, Ω=1,&Lambda=f (162121 MHz)
J′-J=6-5, Ω=2,&Lambda=e,f (236288 MHz)
1989 C2H2 Discovery of Interstellar Acetylene
J. H. Lacy, N. J. Evans II, J. M. Achtermann, D. E. Bruce, J. F. Arens, and J. S. Carr, ApJ 342:L43-L46 (1989)
GL 2591, W3 IRS 5, & OMC-1 IRc2
lines in the 13.7 µm 5
vibration-rotation band
1989 CO2 The Discovery of Interstellar Carbon Dioxide
L. B. D'Hendecourt and M. Jourdain de Muizon, A&A 223:L5-L8 (1989)
AFGL 961, 989, & 890
3 ice feature at 658 cm-1
1989 CH2 A search for methylene in the Orion nebula
J. M. Hollis, P. R. Jewell, P. R. and F. J. Lovas, ApJ 346:794-798 (1989)
Confirmation of Interstellar Methylene
J. M. Hollis, P. R. Jewell, P. R. and F. J. Lovas, ApJ 438:259-264 (1995)
Orion-KL, W51 M
various rotational lines
1990 CP Free CP in IRC+10216
M. Guélin, J. Cernicharo, G. Paubert, and B. E. Turner, A&A 230:L9-L11 (1990)
IRC+10216
10 radio lines
1991 H2C3 Astronomical Detection of H2CCC
J. Cernicharo, C. A. Gottlieb, M Guélin, T. C. Killian, G. Paubert, P. Thaddeus, and J. M. Vrtilek, ApJ 368:L39-L41 (1991)
TMC-1
101 - 000 (20792.59 MHz)
515 - 414 (102992.38 MHz)
514 - 413 (104915.58 MHz)
716 - 615 (146876.06 MHz)
1991 NH Discovery of Interstellar NH
D. M. Meyer and K. C. Roth, ApJ 376:L49-L52 (1991)
Persei & HD 27778
A 3 - X 3 (0,0) R1(0)(3358 Å)
1991 CH4
ASTROMOLECULE OF THE MONTH FOR AUG 2004
Discovery of Interstellar Methane - Observations of Gaseous and Solid CH4 Absorption Toward Young Stars in Molecular Clouds
J. H. Lacy, J. S. Carr, N. J. Evans II, F. Baas, J. M. Achtermann, and J. F. Arens, ApJ 376:556-560 (1991)
NGC 7538, IRS 9, etc.
IR features near 7.6 μm
1991 C2O Detection of a New Carbon-chain Molecule, CCO
M, Ohishi, S.-I. Ishikawa, C. Yamada, H. Kanamori, W. M. Irvine, R. D. Brown, P. D. Godfrey, N. Kaifu, and H. Suzuki. ApJ 380:L39-L42 (1991)
TMC-1
12 01 (22258.181 MHz)
23 12 (45826.706 MHz)
1992 SiN Detection of SiN in IRC+10216
B. E. Turner, ApJ 388:L35-L38 (1992)
IRC+10216
numerous rotational lines
1992 SO+ Detection of Interstellar SO(+) - A Diagnostic of Dissociative Shock Chemistry
B. E. Turner, ApJ 396:L107-L110 (1992)
IC 443G
21/2 J=5/2-3/2, e (115804.405 MHz)
21/2 J=5/2-3/2, f (116179.947 MHz)
21/2 J=9/2-7/2, e (208590.021 MHz)
21/2 J=9/2-7/2, f (208965.425 MHz)
1993 NH2 Detection of the Interstellar NH2 Radical
E. F. van Dishoeck, D. J. Jansen, P. Schilke, and T. G. Phillips, ApJ 416:L83-L86 (1993)
Sgr B2(N) and Sgr B2(M)
J' - J" = 3/2-3/2 (7 lines at 462.4 GHz)
J' - J" = 1/2-1/2 (4 lines at 469.4 GHz)
J' - J" = 3/2-1/2 (5 lines at 461.4 GHz)
1993 CO+ Detection of the Carbon Monoxide Ion (CO+) in the Interstellar Medium and a Planetary Nebula
W. B. Latter, C. K. Walker, and P. R. Maloney, ApJ 419:L97-L100 (1993)
M17SW
(2,1)(3/2-1/2) (235789.641 MHz)
(2,1)(5/2-3/2) (236062.553 MHz)
(3,2)(5/2-3/2) (353741.262 MHz)
1994 HC3NH+ Detection of a New Molecular Ion HC3NH+ in TMC-1
K. Kawaguchi, Y. Kasai, S.-I. Ishikawa, M. Ohishi, N. Kaifu, and T. Amano, ApJ 420:L95-L97(1994)
TMC-1
4-3 (34631.914 MHz)
5-4 (43289.809 MHz)
1994 H2CN Detection of a New Interstellar Molecule, H2CN
M. Ohishi, D. McGonagle, W. M. Irvine, and S. Yamamoto, ApJ 427:L51-L54 (1994)
TMC-1, Sgr B2
10 radio lines
1994 NaCN Detection of Sodium Cyanide (NaCN) in IRC 10216
B. E. Turner, T. C. Steimle, and L. Meerts, ApJ 426:L97-L100 (1994)
IRC+10216
505-404 (77836.7 MHz)
607-505 (93206.1 MHz)
707-606 (108472.0 MHz)
909-808 (138652.1 MHz)
1994 N2O Detection of Interstellar N2O: A New Molecule Containing an N-O Bond
L. M. Ziurys, A. J. Apponi, J. M. Hollis, and L. E. Snyder, ApJ 436:L181-L184 (1994)
Sgr B2
3-2 (75369.2 MHz)
4-3 (100491.7 MHz)
5-4 (125613.7 MHz)
6-5 (150735.0 MHz)
1994 MgCN Detection of MgCN in IRC+10216: A New Metal-Bearing Free Radical
L. M. Ziurys, A. J. Apponi, M. Guélin, and J. Cernicharo, ApJ 445:L47-L50 (1995)
IRC+10216
11-10 (21/2-19/2) (112063.4 MHz)
11-10 (23/2-21/2) (112078.4 MHz)
10-9 (19/2-17/2) (101877.6 MHz)
10-9 (21/2-19/2) (101892.6 MHz)
9-8 (17/2-15/2) (91690.9 MHz)
9-8 (19/2-17/2) (91970.9 MHz)
1996 H3+ Detection of H3+ in Interstellar Space
T. R. Geballe and T. Oka, Nature 384:334-335 (1996)
GL2136, W33A
R(1,0) ortho (2725.898 cm-1)
R(1,1)+ para (2726.219 cm-1)
1996 H2COH+ Detection of a New Interstellar Molecular Ion, H2COH+ (Protonated Formaldehyde)
M. Ohishi, S. Ishikawa, T. Amano, H. Oka, W. M. Irvine, J. E. Dickens, L. M. Ziurys, and A. J. Apponi, ApJ 471:L61-L64 (1996)
Sgr B2, Orion KL, W51
30,3-21,2 (31914.6 MHz)
11,1-20,2 (36300.0 MHz)
40,4-31,3 (102065.8 MHz)
21,1-11,0 (132219.7 MHz)
11,0-10,1 (168401.1 MHz)
50,5-41,4 (173766.9 MHz)
1997 CH3COOH Detection and Confirmation of Interstellar Acetic Acid
D. M. Mehringer, L. E. Snyder, Y. Miao, and F. Lovas, ApJ 480:L71-L74 (1997)
Sgr B2, Orion KL, W51
8*,8-7*,7 E (90203.35 MHz)
8*,8-7*,7 A (90246.26 MHz)
9*,9-8*,8 E (100855.02 MHz)
9*,9-8*,8 A (100897.83 MHz)
1997 HF Discovery of Interstellar Hydrogen Fluoride
D. A. Neufeld, J. Zmuidzinas, P. Schilke, and T. G. Phillips, ApJ 488:L141-L144 (1997)
Sgr B2
J=2-1 (121.6973 μm)
1997 c-C2H4O
ASTROMOLECULE OF THE MONTH FOR JUL 2003
Detection of Interstellar Ethylene Oxide (c-C2H4O)
J. E. Dickens, W. M. Irvine, M. Ohishi, M. Ikeda, S. Ishikawa, A. Nummelin, and A. Hjalmarson, ApJ 489:753-757 (1997)
Sgr B2N
11,1-00,0 (39581.60 MHz)
42,2-41,3 (41579.43 MHz)
55,0-55,4 (47556.90 MHz)
63,4-52,3 (219512.82 MHz)
80,8-71,7 (235106.08 MHz)
55,0-44,1 (249623.57 MHz)
81,7-72,6 (254231.79 MHz)
2000 CH3 Detection of Interstellar CH3
H. Feuchtgruber, F. P. Helmich, E. F. van Dishoeck, and C. M. Wright, ApJ 535:L111-L114 (2000)
Sgr A*
IR spectral match to Q branch at
16.5 µm and R(0) line at 16.0 µm
2000 CH2OHCHO Interstellar Glycolaldehyde: The First Sugar
J. M. Hollis, F. J. Lovas, and P. R. Jewell, ApJ 540:L107-L110 (2000)
Sgr B2(N)
707-616 (71542.7 MHz)
817-726 (73347.3 MHz)
808-717 (82471.2 MHz)
909-818 (93053.2 MHz)
100,10-919 (103392.0 MHz)
1019-928 (103667.4 MHz)
2000 SiCN Astronomical Detection of the Free Radical SiCN
M. Guélin, S. Muller, J. Cernicharo, A. J. Apponi, M. C. McCarthy, C. A. Gottlieb, and P. Thaddeus, A&A 369:L9-L12 (2000)
IRC+10216/CW Leo
7.5-6.5 (83.0 GHz)
8.5-7.5 (94.0 GHz)
9.5-8.5 (105.1 GHz)
2001 C4H2
ASTROMOLECULE OF THE MONTH FOR JUN 2004
Infrared Space Observatory's Discovery of C4H2, C6H2, and Benzene in CRL 618
J. Cernicharo, A. M. Heras, A. G. G. M. Tielens, J. R. Pardo, F. Herpin, M. Guélin, and L. B. F. M. Waters, ApJ 546:L123-L126 (2001)
CRL 618
8 (15.9 µm)
6 + 8 (8 µm)
2001 C6H2 Infrared Space Observatory's Discovery of C4H2, C6H2, and Benzene in CRL 618
J. Cernicharo, A. M. Heras, A. G. G. M. Tielens, J. R. Pardo, F. Herpin, M. Guélin, and L. B. F. M. Waters, ApJ 546:L123-L126 (2001)
CRL 618
11 (16.1 µm)
8 + 11 (8.11 µm)
2001 C6H6 Infrared Space Observatory's Discovery of C4H2, C6H2, and Benzene in CRL 618
J. Cernicharo, A. M. Heras, A. G. G. M. Tielens, J. R. Pardo, F. Herpin, M. Guélin, and L. B. F. M. Waters, ApJ 546:L123-L126 (2001)
CRL 618
4 (14.8374 µm)
2001 CH2CHOH Microwave Detection of Interstellar Vinyl Alcohol, CH2CHOH
B. E. Turner and A. J. Apponi, ApJ 561:L207-L210 (2001)
Sgr B2N, Anti form
111-000 (71830.39 MHz)
212-101 (89757.11 MHz)
313-202 (106949.49 MHz)
414-303 (139315.20 MHz)
515-404 (154460.95 MHz)

Sgr B2N, Syn form
212-101 (86557.60 MHz)
313-202 (103706.01 MHz)
2002 AlNC More Metal Cyanide Species: Detection of AlNC (X 1Sigma+) toward IRC+10216
L. M. Ziurys, C. Savage, J. L. Highberger, A. J. Apponi, M. Guélin, and J.Cernicharo, ApJ 564:L45-L48 (2002)
IRC+10216
11-10 (131642.2 MHz)
12-11 (143605.4 MHz)
13-12 (155567.4 MHz)
18-17 (215357.4 MHz)
21-20 (251213.0 MHz)
2002 FeO Detection of FeO toward Sagittarius B2
C. M. Walmsley, R. Bachiller, G. Pineau des Forêts, and P. Schilke, ApJ 566:L109-L112 (2002)
Sgr B2(N)

J=5-4 (153135.3 MHz)
2002 HOCH2CH2OH
ASTROMOLECULE OF THE MONTH FOR DEC 2003
Interstellar Antifreeze: Ethylene Glycol
J. M. Hollis, F. J. Lovas, P. R. Jewell, and L. H. Coudert, ApJ 571:L59-L62 (2002)
Sgr B2(N-LMH)
845(ν=0)-744(ν=1) (75151.4 MHz)
836(ν=0)-735(ν=1) (75186.1 MHz)
844(ν=0)-743(ν=1) (75186.1 MHz)
707(ν=1)-606(ν=0) (75299.9 MHz)
919(ν=1)-818(ν=0) (92975.9 MHz)
2003 NH2CH2COOH*
ASTROMOLECULE OF THE MONTH FOR SEP 2003
Interstellar Glycine
Y.-J. Kuan, S. B. Charnley, H.-C. Huang, W.-L. Tseng, and Z. Kisiel, ApJ 593:848-867 (2003)
This detection has been disputed:
A Rigorous Attempt to Verify Interstellar Glycine
L. E. Snyder, F. J. Lovas, J. M. Hollis, D. N. Friedel, P. R. Jewell, A. Remijan, V. V. Ilyushin, E. A. Alekseev, S. F. Dyubko, ApJ (in press)
Sgr B2(N-LMH), Orion KL, W51 e1/e2

27 mm-wave lines
2004 N2 The Interstellar N2 Abundance Towards HD 124314 from Far-Ultraviolet Observations
D. C. Knauth, B.-G. Andersson, S. R. McCandliss, H. W. Moos, Nature 409:636-638 (2004)
HD 124314

c'4 1+u X 1+g (958.6 Å)
c3 1+u X 1+g (960.3 Å)
2004 CH2CHCHO Green Bank Telescope Detection of New Interstellar Aldehydes: Propenal and Propanal
J. M. Hollis, P. R. Jewell, F. J. Lovas, A. Remijan, and H. Møllendal, ApJ 610:L21-L24 (2004)
Sgr B2(N)

211-110 (18221.164 MHz)
313-212 (26079.449 MHz)
2004 CH3CH2CHO Green Bank Telescope Detection of New Interstellar Aldehydes: Propenal and Propanal
J. M. Hollis, P. R. Jewell, F. J. Lovas, A. Remijan, and H. Møllendal, ApJ 610:L21-L24 (2004)
Sgr B2(N)

111-000 (21268.611 MHz)
202-101 (20875.059 MHz)
212-111 (19690.426 MHz)
211-110 (22279.346 MHz)
303-212 (21451.572 MHz)
413-404 (19182.445 MHz)
2004 SiNC Detection of the SiNC Radical in IRC+10216
M. Guélin, S. Muller, J. Cernicharo, M. C. McCarthy, and P. Thaddeus, A&A 426:L49-L52 (2004)
IRC+10216

J = 6.5 5.5 (e) (? MHz)
J = 7.5 6.5 (f) (? MHz)
J = 8.5 7.5 (f) (? MHz)
J = 10.5 9.5 (e) (? MHz)
J = 10.5 9.5 (f) (? MHz)
2004 HC4N Detection of the Linear Radical HC4N in IRC+10216
J. Cernicharo, M. Guélin, and J. R. Pardo, ApJ 615:L145-L148 (2004).
IRC+10216

12 radio lines

UV-vis (electron excitations)
mm/sub-mm (rotational excitations)
infrared (vibrational excitations)


Acknowledgements
The NASA ADS archive is indispensable. Other valuable source material:

Maintained by DE Woon
Sponsored by Molecular Research Institute Updated 5 January 2005