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Photometric variability of five candidates for protoplanetary nebulae
Astronomy Letters, 2011We analyze long-term UBV observations and ASAS-3 photometry for five candidates for protoplanetary nebulae—F and G supergiants with infrared excesses at highG alactic latitudes—V340 Ser, IRAS 05113+1347, V552 Pup, V448 Lac, and RV Col. These stars exhibit quasi-periodic multifrequency light variations caused by pulsations with characteristic time ...
V. P. Arkhipova +2 more
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Rossby Wave Propagation and Generation in the Protoplanetary Nebula
Icarus, 1999Abstract The protoplanetary nebular analog to the planetary Rossby wave is developed. Linear dispersion relations are derived. It is found that the nebular Rossby wave propagates freely in the nebular azimuthal direction and slowly grows in the radial direction. Possible ramifications for the nebula are raised for the reverse transition of turbulence
Sanford S. Davis +3 more
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Protoplanetary nebulae – the transition objects
2000The evolutionary stage between the end of the AGB and PN phases has long been a missing link in our understanding of single-star evolution. As we discussed in Chapter 10, the AGB is terminated by the depletion of the H envelope by mass loss, and this occurs before the onset of carbon detonation. When mass loss reduces the mass of the H envelope (M e )
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Blow-off of planetary protoatmospheres and of the protoplanetary nebula
Physics of the Earth and Planetary Interiors, 1982Abstract The mass loss from planetary protoatmospheres is in the order of 10 −2 –10 −4 parts of the planetary mass for the terrestrial planets and about 10 −7 –10 −8 parts for the giant planets. The minimum time intervals needed for the disappearance of the protoplanetary nebula are in the order of 10 6 y in the case of heating by a T-Tauri-like ...
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Molecular lines from protoplanetary nebulae: observations with ALMA
Astrophysics and Space Science, 2007Planetary nebulae (PNe) are formed in a very fast process. In just about 1000 years, the nebula evolves from a spherical and slowly expanding AGB envelope to a PN, with usually axial symmetry and high axial velocities. Molecular lines are known to probe most of the nebular material in young PNe and protoplanetary nebulae (PPNe), and are therefore very ...
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Effects of protoplanetary nebula on orbital dynamics of planetesimals in the outer Solar system
Celestial mechanics & dynamical astronomy, 2019D. Vokrouhlický, D. Nesvorný
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The clearing of protoplanetary disks and of the proto-solar nebula
2010Shogo Tachibana, Ilaria Pascucci
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Chemical and isotopic evolution of the solar nebula and protoplanetary disks
2010Mark H. Thiemens +2 more
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