Abstract
During the last three decades an observational approach has been applied at the Byurakan Astrophysical Observatory to the problems of the evolution of astronomical bodies and systems. In contradiction to the traditional point of view, assuming that the processes of condensation are dominant in the Universe, this approach makes use of the observed predominance of expansions, ejections, and explosions.
In the past, the observational approach has led to the prediction of an expansion of some stellar associations confirmed later by the analysis of observations. It became clear that the stellar associations are very young systems where the star-formation process is still continuing. The new approach has also led to the concept of the activity of galactic nuclei. The observational approach considers as a phenomenon of primary importance the formation of nebulae as a consequence of the activity of dense bodies (nebulae surrounding the novae, planetary nebulae, supernova remnants, cometary nebulae, and the diffuse nebulae in OB-associations).
The new approach in application to the early stages of stellar evolution is discussed. The T Tauri-stage is considered as a phase following the more dense protostellar state. The flare stars are regarded as the next phase of evolution. The phenomena of fuors (FU Ori-type brightenings) can be considered as an expression of the same tendency (the transformation of dense matter into a rarefied state).
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References
Ambartsumian, V. A.: 1937,Astron. Zh. 14, 207.
Ambartsumian, V. A.: 1947,Stellar Evolution and Astrophysics, Acad. Sci. Armenian SSR, Yerevan.
Ambartsumian, V. A.: 1949,Astron. Zh. 26, 3.
Ambartsumian, V. A.: 1953,Compt. Rend. Acad. Sci. Armenian SSR 16 97.
Ambartsumian, V. A.: 1954a, in P. Th. Oosterhoff (ed.),Transactions IAU, Vol. 8, University Press, Cambridge, p. 665.
Ambartsumian, V. A.: 1954b,Contr. Byurakan Obs. 13=1955,Astron. Popular (Mexico) 2, 27.
Ambartsumian, V. A.: 1954c,Contr. Byurakan Obs. 15.
Ambartsumian, V. A.: 1957a,Vestnik Acad. Sci. USSR,11, 45.
Ambartsumian, V. A.: 1957b, in G. H. Herbig (ed.), ‘Non-Stable Stars’,IAU Symp. 3, 177.
Ambartsumian, V. A.: 1958,La structure et l'evolution de l'Univers, Editions Stoops, Bruxelles, p. 241.
Ambartsumian, V. A.: 1962,Voprosy Kosmogonii 8, 3.
Ambartsumian, V. A.: 1969,Stars, Nebulae, Galaxies, Byurakan Symposium, Acad. Sci. Armenian SSR, Yerevan, p. 283.
Ambartsumian, V. A.: 1970,Astrofizika 6, 31.
Ambartsumian, V. A.: 1971,Astrofizika 7, 557.
Ambartsumian, V. A. and Mirzoyan, L. V.: 1971, in ‘New Directions and New Frontiers in the Variable Star Research’,IAU Colloq. 15, 98.
Ambartsumian, V. A. and Mirzoyan, L. V.: 1975, in V. Sherwood and L. Plaut (eds.), ‘Variable Stars and Stellar Evolution’,IAU Symp. 67, 3.
Ambartsumian, V. A. and Mirzoyan, L. V.: 1976, in V. A. Ambartsumian (ed.),Probleme der Modernen Kosmogonie, Birkhäuser Verlag, Basel, Stuttgart, Chapters I and II.
Ambartsumian, V. A. and Sahakian, G. S.: 1960a,Astron. Zh. 37, 193.
Ambartsumian, V. A. and Sahakian, G. S.: 1960b,Voprosy Kosmogonii 9, 3.
Ambartsumian, V. A., Mirzoyan, L. V., Parsamian, E. S., Chavushian, H. S., and Erastova, L. K.: 1970,Astrofizika 6, 3.
Blaauw, A.: 1952,Bull. Astron. Inst. Netherlands 12, 405.
Blaauw, A.: 1964,Ann. Rev. Astron. Astrophys. 2, 213.
Blaauw, A.: 1978, in L. V. Mirzoyan (ed.),Problems of Physics and Evolution of the Universe, Acad. Sci. Armenian SSR, Yerevan, p. 101.
Cantó, J., Rodríguez, L. F., Barral, J. F., and Carral, P.: 1981,Astrophys. J. 244, 102.
Chavushian, H. S.: 1979,A Study of Flare Stars in the Pleiades Aggregate Region, Byurakan Astrophys. Obs.
Clark, D. H. and Murdin, P.: 1978,Nature 276, 44.
Grasdalen, G., Gehrz, R. D., Joyce, R., Knacke, R. F., Strom, S. E., and Strom, K. M.: 1975,Astron. J. 80, 177.
Gyulbudagian, A. L.: 1980, in L. V. Mirzoyan (ed.),Flare Stars, Fuors and Herbig-Haro Objects, Acad. Sci. Armenian SSR, Yerevan, p. 247.
Gyulbudagian, A. L. and Magakian, T. Y.: 1977,Compt. Rend. Acad. Sci. Armenian SSR64, 104.
Hackwell, J. A., Gehrz, R. D., and Grasdalen, G. L.: 1979,Astrophys. J. 234, 133.
Haro, G.: 1957, in G. H. Herbig (ed.), ‘Non-Stable Stars’,IAU Symp. 3, 26.
Haro, G.: 1968, in B. M. Middlehurst and L. H. Aller (eds.),Stars and Stellar Systems Vol. 7. University Press, Chicago, p. 141.
Haro, G.: 1976,Bol. Inst. Tonantzintla 2, 3.
Haro, G. and Chavira, E.: 1966, in A. Beer and K. Aa. Strand (eds.),Vistas Astron. 8, Pergamon Press, London, p. 89.
Herbig, G. H.: 1958,Astrophys. J. 128, 259.
Herbig, G. H.: 1962,Adv. Astron. Astrophys. 1, 47.
Herbig, G. H.: 1967,Scientific Am. 217, No. 2, 30.
Herbig, G. H.: 1969, in L. Detre (ed.), ‘Non-Periodic Phenomena in Variable Stars’,IAU Colloq. 4, 75.
Herbig, G. H.: 1974,Lick Obs. Bull., No. 658.
Herbig, G. H.: 1977,Astrophys. J. 214, 747.
Hoyle, F.: 1980,Steady-State Cosmology Revisited, University College, Cardiff.
Mezger, P. G. and Smith, L. F.: 1977, in T. de Jong and A. Maeder (eds.), ‘Star Formation’,IAU Symp. 75, 133.
Mezger, P. G.: 1978,Astron. Astrophys. 70, 565.
Mirzoyan, L. V.: 1961,Contr. Byurakan Obs. 29, 81.
Mirzoyan, L. V.: 1966, in J.-C. Pecker (ed.),Transactions IAU 13B, Academic Press, London, New York, p. 419.
Mirzoyan, L. V.: 1976, in E. K. Kharadze (ed.),Stars and Galaxies From Observational Points of View, Proc. III European Astronomical Meeting, Acad. Sci. Georgian SSR, Tbilisi, p. 121.
Mirzoyan, L. V.: 1977, in R. Kippenhahn, J. Rahe, and W. Strohmeier (eds.), ‘The Interaction of Variable Stars with Their Environment’,IAU Colloq. 42, 126.
Mirzoyan, L. V.: 1978, in L. V. Mirzoyan (ed.),Problems of Physics and Evolution of the Universe, Acad. Sci. Armenian SSR, Yerevan, p. 209.
Mirzoyan, L. V. and Mnatsakanian, M. A.: 1970,Astrofizika 6, 411.
Mirzoyan, L. V., Chavushian, H. S., Erastova, L. K., Ohanian, G. B., Melikian, N. D., Natsvlishvili, R. Sh., and Tsvetkov, M. K.: 1977,Astrofizika 13, 205.
Poveda, A.: 1965,Bol. Obs. Tonantzintla 4, 15.
Rodriguez, L. F., Moran, J. M., Ho, P. T. P., and Gottlieb, E. W.: 1980,Astrophys. J. 235, 845.
Sahakian, G. S.: 1972,Equilibrium Configurations of Degenerate Gas Masses, Nauka, Moscow.
Schneeberger, T. J., Worden, S. P., and Wilkerson, M. S.: 1979,Astrophys. J. Suppl. 41, 369.
Strom, K. M., Strom, S. E., Breger, M., Brooke, A. L., Yost, J., Grasdalen, G., and Carrasco, L.: 1972a,Astrophys. J. 173, L65.
Strom, S. E., Strom, K. M., Yost, J., Carrasco, L., and Grasdalen, G.: 1972b,Astrophys. J. 173, 353.
Tsvetkov, M. K.: 1976,A Study of Non-Stable Stars in the NGC 7000 and IC 5068-70 Nebulae Region in the Cygnus, Yerevan University.
Walker, M. F.: 1963,Astron. J. 68, 298.
Welin, G.: 1971,Astron. Astrophys. 12, 312.
Yankovics, I.: 1965,Flare Activity of Red Dwarf Stars in the Praesepe Cluster Region, Yerevan University.
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Ambartsumian, V.A., Mirzoyan, L.V. An observational approach to the early stages of stellar evolution. Astrophys Space Sci 84, 317–330 (1982). https://doi.org/10.1007/BF00651314
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DOI: https://doi.org/10.1007/BF00651314