Back سديم كوكبي أولي Arabic Протапланетарная туманнасць BE Protoplanetarna maglina BS Nebulosa protoplanetària Catalan Protoplanetární mlhovina Czech Protonebulosa planetaria Spanish سحابی پیشسیارهای FA Esiplanetaarinen sumu Finnish Protonébuleuse planétaire French Protoplanetáris köd Hungarian
A protoplanetary nebula or preplanetary nebula[1] (PPN, plural PPNe) is an astronomical object which is at the short-lived episode during a star's rapid evolution between the late asymptotic giant branch (LAGB)[a] phase and the subsequent planetary nebula (PN) phase. A PPN emits strongly in infrared radiation, and is a kind of reflection nebula. It is the second-from-the-last high-luminosity evolution phase in the life cycle of intermediate-mass stars (1–8 M☉).[2]: 469
- ^ Sahai, Raghvendra; Sánchez Contreras, Carmen; Morris, Mark (2005). "A Starfish Preplanetary Nebula: IRAS 19024+0044" (PDF). The Astrophysical Journal. 620 (2): 948–960. Bibcode:2005ApJ...620..948S. doi:10.1086/426469.
- ^ Kastner, J. H. (2005), "Near-death Transformation: Mass Ejection in Planetary Nebulae and Protoplanetary Nebulae", American Astronomical Society Meeting 206, #28.04; Bulletin of the American Astronomical Society, 37, Bibcode:2005AAS...206.2804K