Log in

Ultracompact HII regions: the impact of newly formed massive stars on their environment

  • Published:
The Astronomy and Astrophysics Review Aims and scope

Summary

Ultracompact (UC)HII regions are manifestations of newly formed massive stars that are still embedded in their natal molecular cloud. They are among the brightest and most luminous single objects in the Galaxy at far infrared and radio wavelengths. Recent high spatial resolution studies, particularly at radio wavelengths, have greatly contributed to our understanding of these dynamic objects and the impact they have on their environment. A summary is given of our current understanding of the physical properties, morphologies, dynamics, number and distribution in the Galaxy, and molecular environments of UCHII regions. Recent models of the circumnebular dust imply that the graphite/silicate abundance ratio is about half that of dust in the diffuse interstellar medium. The dust cocoons are large, cool, and optically thick shortward of a few microns. There are apparently between 1700 and 3000 UCHII regions in the Galaxy. This represents 10–20% of the total O star population. There are too many UCHII regions (just counting those studied with the VLA) to be consistent with the short dynamical lifetimes of this very compact stage of evolution. Both the morphologies and the large number can be understood if UC HII regions are bow shocks. Models of stellar wind supported bow shocks are discussed and consequences for the dynamics and morphologies of the ionized and molecular gas are explored.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Subscribe and save

Springer+ Basic
EUR 32.99 /Month
  • Get 10 units per month
  • Download Article/Chapter or Ebook
  • 1 Unit = 1 Article or 1 Chapter
  • Cancel anytime
Subscribe now

Buy Now

Price includes VAT (Germany)

Instant access to the full article PDF.

Similar content being viewed by others

References

  • Andersson, M., Garay, G.: 1986,Astron. Astrophys. 167, L1

    Google Scholar 

  • Baldwin, J.E., Harris, S., Ryle, M.: 1973,Nature 241, 38

    Google Scholar 

  • Balick, B.: 1972,Astrophys. J. 176, 353

    Google Scholar 

  • Bally, J., Predmore, R.: 1983,Astrophys. J. 265, 778

    Google Scholar 

  • Beckwith, S., Sargent, A.I., Scoville, N.Z., Masson, C.R., Zuckerman, B., Phillips, T.G.: 1986,Astrophys. J. 309, 755

    Google Scholar 

  • Beichman, C.A.: 1979, Ph. D. Thesis, Univ. Hawaii

  • Beichman, C.A., Becklin, E.E., Wynn-Williams, C.G.: 1979,Astrophys. J. 232, L47

    Google Scholar 

  • Bed**, P.J., Tenorio-Tagle, G.: 1981,Astron. Astrophys. 98, 85

    Google Scholar 

  • Benson, J.M., Johnston, K.J.: 1984,Astrophys. J. 277, 181

    Google Scholar 

  • Blake, G.A., Sutton, E.C., Masson, C.R., Phillips, T.G.: 1987,Astrophys. J. 315, 621

    Google Scholar 

  • Bodenheimer, P., Tenorio-Tagle, G., Yorke, H.W.: 1979,Astrophys. J., 233, 85

    Google Scholar 

  • Bronfman, L., May, J., Nyman, L.: 1990 (in preparation)

  • Brown, R.L.: 1974,Astrophys. J. 194, L9

    Google Scholar 

  • Brown, R.L., Zuckerman, B.: 1975,Astrophys. J. 202, L125

    Google Scholar 

  • Brown, R.L., Johnston, K.J., Lo, K.Y.: 1981,Astrophys. J. 250, 155

    Google Scholar 

  • Campbell, B.: 1984,Astrophys. J. 287, 334

    Google Scholar 

  • Chini, R., Kreysa, E., Mezger, P.G., Gemünd, H.-P.: 1986a,Astron. Astrophys. 154, L8

    Google Scholar 

  • Chini, R., Kreysa, E., Mezger, P.G., Gemünd, H.-P.: 1986b,Astron. Astrophys. 157, L1

    Google Scholar 

  • Chini, R., Krügel, E., Wargau, W.: 1987,Astron. Astrophys. 181, 378

    Google Scholar 

  • Churchwell, E.: 1988, “Ultracompact HII Regions: Their Morphologies and Spectral Energy Distributions” in Galactic and Extragalactic Star Formation, eds. R.E. Pudritz, M. Fich, NATO ASI Series, Kluwer Academic Publications, Dordrecht, p. 275

    Google Scholar 

  • Churchwell, E., Felli, M., Wood, D.O.S., Massi, M.: 1987,Astrophys. J. 321, 516

    Google Scholar 

  • Churchwell, E., Walmsley, C.M., Cesaroni, R.: 1990,Astron. Astrophys. Suppl. (in press)

  • Churchwell, E., Wolfire, M.G., Wood, D.O.S.: 1990,Astrophys. J. 354, 247.

    Google Scholar 

  • Colley, D.: 1980,Monthly Notices Roy. Astron. Soc. 193, 495

    Google Scholar 

  • Dame, T.M., Ungerechts, R.S., Cohen, R.S., De Geus, E.J., Grenier, I.A., May, J., Murphy, D.D., Nyman, L.-Å, Thaddeus, P.: 1987,Astrophys. J. 322, 706

    Google Scholar 

  • de Muizon, M., Cox, P., Lequeux, J.: 1990,Astron. Astrophys. (in press)

  • Dieter, N.J., Welch, W.J., Wright, M.C.H.: 1979,Astrophys. J. 230, 738

    Google Scholar 

  • Downes, D., Winnberg, A., Goss, W.M., Johansson, L.E.B.: 1975,Astron. Astrophys. 44, 243

    Google Scholar 

  • Draine, B.T.: 1985,Astrophys. J. Suppl. 57, 587

    Google Scholar 

  • Draine, B.T., Lee, H.M.: 1984,Astrophys. J. 285, 89

    Google Scholar 

  • Draine, B.T., Lee, H.M.: 1987,Astrophys. J. 318, 485

    Google Scholar 

  • Dreher, J.W., Johnston, K.J., Welch, W.J., Walker, R.C.: 1984,Astrophys. J. 283, 632

    Google Scholar 

  • Dreher, J.W., Welch, Wm.J.: 1981,Astrophys. J. 245, 857

    Google Scholar 

  • Evans, N.J., Beckwith, S., Brown, R.L., Gilmore, W.: 1979,Astrophys. J. 227, 450

    Google Scholar 

  • Felli, M., Churchwell, E., Massi, M.: 1984,Astron. Astrophys. 136, 53

    Google Scholar 

  • Felli, M., Johnston, M.J., Churchwell, E.: 1980,Astrophys. J. 242, L157

    Google Scholar 

  • Forster, J.R., Caswell, J.L., Okumura, S.K., Hasegawa, T., Ishiguro, M.: 1990,Astron. Astrophys. (in press)

  • Garay, G.: 1989, private communication

  • Garay, G., Moran, J.M., Reid, M.J.: 1987,Astrophys. J. 314, 535

    Google Scholar 

  • Garay, G., Reid, M.J., Moran, J.M.: 1985,Astrophys. J. 289, 681

    Google Scholar 

  • Garay, G., Rodriguez, L.F., van Gorkom, J.H.: 1986,Astrophys. J. 309, 553

    Google Scholar 

  • Gatley, I., Becklin, E.E., Werner, M.W., Harper, D.A.: 1978,Astrophys. J. 220, 822

    Google Scholar 

  • Gaume, R.A., Claussen, M.J.: 1990,Astrophys. J. 351, 538

    Google Scholar 

  • Gaume, R.A., Mutel, R.L.: 1987,Astrophys. J. Suppl. 65, 193

    Google Scholar 

  • Genzel, R., Becklin, E.E., Wynn-Williams, C.G., Moran, J.M., Reid, M.J., Jaffe, D.T., Downes, D.: 1982,Astrophys. J. 255, 527

    Google Scholar 

  • Goss, W.M., Matthews, H.E., Winnberg, A.: 1978,Astron. Astrophys. 65, 307

    Google Scholar 

  • Goss, W.M., Tilanus, R.P.J.: 1985,Monthly Notices Roy. Astron. Soc. 215, 197

    Google Scholar 

  • Habing, H.J., Israel, F.P., de Jong, T.: 1972,Astron. Astrophys. 17, 329

    Google Scholar 

  • Habing, H.J., Matthews, H.E., Goss, W.M., Winnberg, A.: 1974,Astron. Astrophys. 35, 1

    Google Scholar 

  • Harris, S.: 1973,Monthly Notices Roy. Astron. Soc. 162, p. 5

    Google Scholar 

  • Harris, S.: 1974,Monthly Notices Roy. Astron. Soc. 166, p. 29

    Google Scholar 

  • Harris, S.: 1975,Monthly Notices Roy. Astron. Soc. 170, 139

    Google Scholar 

  • Harris, S., Scott, P.F.: 1976,Monthly Notices Roy. Astron. Soc. 175, 371

    Google Scholar 

  • Harris, S., Wynn-Williams, C.G.: 1976,Monthly Notices Roy. Astron. Soc. 174, 649

    Google Scholar 

  • Harten, R.H.: 1976,Astron. Astrophys. 46, 109

    Google Scholar 

  • Harvey, P.M., Forvielle, T.: 1988,Astron. Astrophys. 197, L19

    Google Scholar 

  • Haschick, A.D., Ho, P.T.P.: 1983,Astrophys. J. 267, 638

    Google Scholar 

  • Haschick, A.D., Menten, K.M., Baan, W.A.: 1990,Astrophys. J. (in press)

  • Henkel, C., Churchwell, E.: 1991 (in preparation)

  • Henkel, C., Wilson, T.L., Mauersberger, R.: 1987,Astron. Astrophys. 182, 137

    Google Scholar 

  • Ho, P.T.P., Genzel, R., Das, A.: 1983,Astrophys. J. 266, 596

    Google Scholar 

  • Ho, P.T.P., Haschick, A.D.: 1981,Astrophys. J. 248, 622

    Google Scholar 

  • Ho, P.T.P., Haschick, A.D.: 1986,Astrophys. J. 304, 501

    Google Scholar 

  • Ho, P.T.P., Hashick, A.D., Israel, F.P.: 1981,Astrophys. J. 243, 526

    Google Scholar 

  • Ho, P.T.P., Klein, R.I., Haschick, A.D.: 1986,Astrophys. J. 305, 714

    Google Scholar 

  • Hoare, M.G., Glencross, W.M., Roche, P.F., Clegg, R.E.S.: 1988, “The Dust Content of Nebulae” in Dust in the Universe, ed. M.E. Bailey and D.A. Williams, Cambridge University Press, pp. 107–112

  • Hughes, V.A.: 1985,Astrophys. J. 298, 830

    Google Scholar 

  • Hughes, V.A.: 1988,Astrophys. J. 333, 788

    Google Scholar 

  • Hughes, V.A., MacLeod, G.C.: 1989,Astron. J. 97, 786

    Google Scholar 

  • Hughes, V.A., Wouterloot, J.G.A.: 1984,Astrophys. J. 276, 204

    Google Scholar 

  • Israel, F.P.: 1976,Astron. Astrophys. 48, 193

    Google Scholar 

  • Israel, F.P.: 1977a,Astron. Astrophys. 60, 233

    Google Scholar 

  • Israel, F.P.: 1977b,Astron. Astrophys. 61, 377

    Google Scholar 

  • Israel, F.P., Felli, M.: 1978,Astron. Astrophys. 63, 325

    Google Scholar 

  • Israel, F.P., Habing, H.J., de Jong, T.: 1973,Astron. Astrophys. 27, 143

    Google Scholar 

  • Jackson, J.M., Ho, P.T.P., Haschick, A.D.: 1988,Astrophys. J. 333, L73

    Google Scholar 

  • Keto, E.R., Ho, P.T.P., Haschick, A.D.: 1987,Astrophys. J. 318, 712

    Google Scholar 

  • Keto, E.R., Ho, P.T.P., Haschick, A.D.: 1988,Astrophys. J. 324, 920

    Google Scholar 

  • Keto, E.R., Ho, P.T.P., Reid, M.J.: 1987,Astrophys. J. 323, L117

    Google Scholar 

  • Krassner, J., Pipher, J.L., Sharpless, S.: 1979,Astron. Astrophys. 77, 302

    Google Scholar 

  • Krügel, E., Mezger, P.G.: 1975,Astron. Astrophys. 42, 441

    Google Scholar 

  • Kurtz, S., Wood, D.O.S., Churchwell, E.: 1990 (in preparation)

  • Kurtz, S., Wood, D.O.S., Myers, P., Bronfman, L., Churchwell, E.: 1991 (in preparation)

  • Lee, H.M., Draine, B.T.: 1985,Astrophys. J. 290, 211

    Google Scholar 

  • Leung, C.M.: 1976,Astrophys. J. 209, 75

    Google Scholar 

  • Mac Low, M.-M., Van Buren, D., Wood, D.O.S., Churchwell, E.: 1990,Astrophys. J. (submitted)

  • Martin, A.H.M.: 1972,Monthly Notices Roy. Astron. Soc. 157, 31

    Google Scholar 

  • Martin, A.H.M.: 1973,Monthly Notices Roy. Astron. Soc. 163, 141

    Google Scholar 

  • Massi, M., Felli, M., Simon, M.: 1985,Astron. Astrophys. 152, 387

    Google Scholar 

  • Mathis, J.S., Rumpl, W., Nordsieck, K.H.: 1977,Astrophys. J. 217, 425 (MRN)

    Google Scholar 

  • Matthews, H.E., Goss, W.M., Winnberg, A., Habing, H.J.: 1973,Astron. Astrophys. 29, 309

    Google Scholar 

  • Matthews, H.E., Goss, W.M., Winnberg, A., Habing, H.J.: 1977,Astron. Astrophys. 61, 261

    Google Scholar 

  • Matthews, H.E., Shaver, P.A., Goss, W.M., Habing, H.J.: 1978,Astron. Astrophys. 63, 307

    Google Scholar 

  • Mauersberger, R., Henkel, C., Wilson, T.L., Walmsley, C.M.: 1986,Astron. Astrophys. 162, 199

    Google Scholar 

  • Menten, K.M. 1987, Ph. D. Thesis, Rheinischen-Friedrich-Wilhelms-Universität zu Bonn

  • Miley, G.K., Turner, B.E., Balick, B., Heiles, C.: 1970,Astrophys. J. 160, L119

    Google Scholar 

  • Moran, J.M., Garay, G., Reid, M.J., Genzel, R., Wright, M.C.H., Plambeck, R.L.: 1983,Astrophys. J. 271, L31

    Google Scholar 

  • Reid, M.J., Ho, P.T.P.: 1985,Astrophys. J. 288, L17

    Google Scholar 

  • Rodriguez, L.F., Canto, J., Moran, J.M.: 1982,Astrophys. J. 255, 103

    Google Scholar 

  • Rodriguez, L.F., Canto, J.: 1983,Rev. Mex. Astron. Astrophys. 8, 163

    Google Scholar 

  • Rodriguez, L.F., Canto, J., Moran, J.M.: 1988,Astrophys. J. 333, 801

    Google Scholar 

  • Roelfsema, P.R., Goss, W.M., Whiteoak, J.B., Gardner, F.F., Pankonin, V.: 1987,Astron. Astrophys. 175, 219

    Google Scholar 

  • Rodriguez, L.F., Moran, J.M., Ho, P.T.P., Gottlieb, E.W.: 1980,Astrophys. J. 235, 845

    Google Scholar 

  • Ryle, M., Downes, D.: 1967,Astrophys. J. 148, L17

    Google Scholar 

  • Scalo, J.M.: 1986,Fund. Cosmic Phys. 11, 1

    Google Scholar 

  • Scott, P.F.: 1978,Monthly Notices Roy. Astron. Soc. 183, 435

    Google Scholar 

  • Simon, M., Righini-Cohen, G., Felli, M., Fischer, J.: 1981,Astrophys. J. 245, 552

    Google Scholar 

  • Simon, M., Felli, M., Cassar, L., Fischer, J., Massi, M.: 1983,Astrophys. J. 266, 623

    Google Scholar 

  • Snell, R.L., Bally, J.: 1986,Astrophys. J. 303, 683

    Google Scholar 

  • Sodroski, T.J.: 1988, Ph. D. Thesis, University of Maryland

  • Tenorio-Tagle, G.: 1979,Astron. Astrophys. 71, 59

    Google Scholar 

  • Tenorio-Tagle, G., Yorke, H.W., Bodenheimer, P.: 1979,Astron. Astrophys. 80, 110

    Google Scholar 

  • Tielens, A.G.G.M., de Jong, T.: 1979,Astron. Astrophys. 75, 326

    Google Scholar 

  • Torrelles, J.M., Ho, P.T.P., Rodriguez, L.F., Canto, J.: 1985,Astrophys. J. 288, 595

    Google Scholar 

  • Torrelles, J.M., Ho, P.T.P., Rodriguez, L.F., Canto, J.: 1986,Astrophys. J. 305, 721

    Google Scholar 

  • Turner, B.E., Balick, B., Cudaback, D.D., Heiles, C., Boyle, R.J.: 1974,Astrophys. J. 194, 279

    Google Scholar 

  • Turner, B.E., Matthews, H.E.: 1984,Astrophys. J. 277, 164

    Google Scholar 

  • Turner, B.E., Welch, W.J.: 1984,Astrophys. J. 287, L81

    Google Scholar 

  • Tutukov, A.V., Shustov, B.M.: 1981,Soviet Ast. 58, 109

    Google Scholar 

  • Van Buren, D., Mac Low, M.-M., Wood, D.O.S., Churchwell, E.: 1990,Astrophys. J. 353 (in press)

  • Walmsley, C.M.: 1989, “Dust and the Gas Phase Composition of Dense Clouds” in Interstellar Dust, IAU Symp. No. 135, eds. L.J. Allamandola and A.G.G.M. Tielens, Kluwer Academic Pub., Dordrecht, p. 263

    Google Scholar 

  • Walmsley, C.M., Baudry, A., Guilloteau, S., Winnberg, A.: 1986,Astron. Astrophys. 167, 151

    Google Scholar 

  • Webster, W.J., Altenhoff, W.J.: 1970a,Astronomical J. 75, 896

    Google Scholar 

  • Webster, W.J., Altenhoff, W.J.: 1970b,Astrophys. Lett. 5, 233

    Google Scholar 

  • Webster, W.J., Altenhoff, W.J., Wink, J.E.: 1971,Astron. J. 76, 677

    Google Scholar 

  • Welch, W.J., Dreher, J.W., Jackson, J.M., Terebey, S., Vogel, S.N.: 1987,Science, 238, 1550

    Google Scholar 

  • Weliachew, L., Emerson, D.T., Forveille, T., Bieging, J.H., Wright, M.C.H., Ellder, J.: 1985,Astron. Astrophys. 153, 139

    Google Scholar 

  • Wendker, H.J., Baars, J.W.M.: 1974,Astron. Astrophys. 33, 157

    Google Scholar 

  • Wilson, T.L., Mausersberger, R., Walmsley, C.M., Batria, W.: 1983,Astron. Astrophys. 127, L19

    Google Scholar 

  • Wink, J., Altenhoff, W.J., Webster, W.J.: 1973,Astron. Astrophys. 22, 251

    Google Scholar 

  • Wink, J., Altenhoff, W.J., Webster, W.J.: 1975,Astron. Astrophys. 38, 109

    Google Scholar 

  • Wink, J., Altenhoff, W.J., Mezger, P.G.: 1982,Astron. Astrophys. 108, 227

    Google Scholar 

  • Winnberg, A., Habing, H.J., Goss, W.M.: 1973,Nature, 243, 78

    Google Scholar 

  • Wolfire, M.G., Cassinelli, J.P.: 1986,Astrophys. J. 310, 207

    Google Scholar 

  • Wood, D.O.S., Churchwell, E.: 1989a,Astrophys. J. Suppl. 69, 831

    Google Scholar 

  • Wood, D.O.S., Churchwell, E.: 1989b,Astrophys. J. 340, 265

    Google Scholar 

  • Wynn-Williams, C.G.: 1969 a,Monthly Notices Roy. Astron. Soc. 142, 453

    Google Scholar 

  • Wynn-Williams, C.G.: 1969 b,Astrophys. Lett. 3, 195

    Google Scholar 

  • Wynn-Williams, C.G.: 1971,Monthly Notices Roy. Astron. Soc. 151, 397

    Google Scholar 

  • Wynn-Williams, C.G.: 1982,Ann Rev. Astronomy-Astrophys. 20, 587

    Google Scholar 

  • Wynn-Williams, C.G., Becklin, E.E.: 1974,Pub. Ast. Soc. Pacific, 86, 5

    Google Scholar 

  • Wynn-Williams, C.G., Becklin, E.E., Forster, J.R., Matthews, K., Neugebauer, G., Welch, W.J., Wright, M.C.H.: 1977,Astrophys. J. 211, L89

    Google Scholar 

  • Wynn-Williams, C.G., Becklin, E.E., Neugebauer, G.: 1972,Monthly Notices Roy. Astron. Soc. 160, 1

    Google Scholar 

  • Wynn-Williams, C.G., Beichman, C.A., Downes, D.: 1981,Astron. J. 86, 565

    Google Scholar 

  • Wynn-Williams, C.G., Downes, D., Wilson, T.L.: 1971,Astrophys. Lett. 9, 113

    Google Scholar 

  • Yorke, H.W.: 1979,Astron. Astrophys. 80, 308

    Google Scholar 

  • Yorke, H.W.: 1980,Astron. Astrophys. 85, 215

    Google Scholar 

  • Yorke, H.W., Krügel, E.: 1977,Astron. Astrophys. 54, 183

    Google Scholar 

  • Yorke, H.W., Shustov, B.M.: 1981,Astron. Astrophys. 98, 125

    Google Scholar 

  • Yorke, H.W., Tenorio-Tagle, G., Bodenheimer, P.: 1983,Astron. Astrophys. 127, 313

    Google Scholar 

  • Zheng, X.W., Ho, P.T.P., Reid, M.J., Schneps, M.H.: 1985,Astrophys. J. 293, 522

    Google Scholar 

  • Zuckerman, B.: 1973,Astrophys. J. 183, 863

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Churchwell, E. Ultracompact HII regions: the impact of newly formed massive stars on their environment. The Astron Astrophys Rev 2, 79–123 (1990). https://doi.org/10.1007/BF00872764

Download citation

  • Received:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF00872764

Key words

Navigation