Editorial: Planetary nebulae as tools for astrophysics

PEÑA, MIRIAM; KWITTER, KAREN B.; MILLER BERTOLAMI, MARCELO MIGUEL; MORISSET, CHRISTOPHE; RICHER, MICHAEL

Frontiers in Astronomy and Space Sciences

Frontiers Media SA

Lugar: Laussane; Año: 2023 vol. 10

Planetary nebulae (PNe) represent the ejected outer layers of an evolved low-to-intermediate mass star, and consist of ionized, neutral, and molecular components, along with dust. In total, the nebular material contains the stellar envelope that was ejected during the asymptotic-giant branch (AGB) phase or through binary interactions with a companion. The PN central star is formed by the former core of the AGB or red-giant branch progenitor of the PN, which is now contracting towards the white dwarf phase. The PN central star is a post-AGB object which has evolved crossing the Hertzsprung-Russell diagram, and has an effective temperature of 28,000 K up to more than 250,000 K. It emits a large fraction of its light as UV photons that ionize the envelope. PNe are mainly studied through imaging, photometry and low- and high-resolution spectroscopy techniques which allow determination of the physical conditions and chemical abundances in the nebula. Through this kind of analysis it is possible to study the physical processes in ionized plasmas, the evolution and characteristics of the central star, along with the mechanisms of ejection of the nebula and the evolution of the interstellar medium – in external galaxies as well as in the Milky Way – which will be enriched with elements produced in the stellar nucleosynthesis and brought to the stellar surface via several dredge-up episodes. Further, an accurate census of PNe provides an important constraint on a galaxy’s star formation history. PNe are also useful in studying the kinematics of galaxies and their distances through the [O III] λ5007 Planetary Nebula Luminosity Function which is currently a secondary standard candle out to 20 Mpc.The aim of this Research Topic is to present up-to-date articles from leading researchers on several of the above-mentioned areas of PNe studies; these are summarized below.