Planetary Nebulae: Sources of Enlightenment

Abstract

In this review/tutorial we explore planetary nebulae as a stage in the evolution of low-to-intermediate-mass stars, as major contributors to the mass and chemical enrichment of the interstellar medium, and as astrophysical laboratories. We discuss many observed properties of planetary nebulae, placing particular emphasis on element abundance determinations and comparisons with theoretical predictions. Dust and molecules associated with planetary nebulae are considered as well. We then examine distances, binarity, and planetary nebula morphology and evolution. We end with mention of some of the advances that will be enabled by future observing capabilities.

The Planetary Nebula in the 500 Myr Old Open Cluster M37

“…Their strong emission lines allow the determination of abundances, expansion and radial velocities, and CSPN temperatures. PNe yield information on the nuclear burning, dredge up, and mass loss in the stellar progenitor (see Kwitter & Henry 2022 for an excellent recent PN review). PN studies have been hampered by three problems: (i) the previous lack of accurate distances to most Galactic PNe; (ii) obtaining representative PNe samples of the true population diversity (Parker 2022), and (iii) their unknown progenitor masses.…”

Planetary nebulae and how to find them: A concise review

“…Selected specific PNe reviews include Miller (1974) and Balick and Frank (2002), while a review of all PNe research just from 2014 is given by Zijlstra (2015) while recent work on finding PNe in broad band surveys was reported by Vejar et al (2019). Finally, I recommend the excellent, recent review of Kwitter and Henry (2022). This paper is not intended to compete with these materials for PNe but adopts a more practical approach to reviewing the techniques and processes used and available to actually find PNe and to use them for science with the help of the Hong Kong/AAO/Strasbourg/Hα PNe catalogue (HASH) PNe database, Parker et al (2016) and see Section 12 later.…”

FAST search for circumstellar atomic hydrogen--I: the young planetary nebula IC 4997

“…Many PNe are ionization bounded, where part of the matter lost by the stellar wind during the pre-PN stage has not yet been ionized by the central star. A substantial part of their envelope may remain neutral (see, e.g., Kwitter & Henry 2022, for a review). These outer regions of PNe show dust emission, but the abundance of refractory elements limits the dust mass to no more than 1% of the total mass of the nebula.…”