Related papers: Molecules as Tracers of PN Structure

Recent molecular line observations with ALMA in several nearby Seyferts have revealed the existence of molecular tori, and the nature of gas flows at 10-20~pc scale. At 100~pc scale, or kpc-scale, previous NOEMA work on gravitational…

The study of the chemical composition of Planetary Nebulae in external galaxies is of paramount importance in the fields of stellar evolution and of the chemical enrichment history of galaxies. In the last years a number of spectroscopic…

We have carried out a systematic search for the molecular ion CO+ in a sample of 8 protoplanetary and planetary nebulae in order to determine the origin of the unexpectedly strong HCO+ emission previously detected in these sources. An…

Considerable progress has been made in understanding the hydrodynamics, but only to a certain extent the magnetohydrodynamics, of shaping bipolar outflows forming protoplanetary nebulae (PPNs) and planetary nebulae (PNs). In particular,…

Observations indicate that molecular clouds are strongly magnetized, and that magnetic fields influence the formation of stars. A key observation supporting the conclusion that molecular clouds are significantly magnetized is that the…

The question whether magnetic fields play an important role in the processes of molecular cloud and star formation has been debated for decades. Recent observations have revealed a simple picture that may help illuminate these questions:…

A large class of stellar systems (e.g., planetary nebulae (PNe), supernova envelopes, LBV stars, young stars in formation) shows structures in their accretion/ejection phase that have similar characteristics. In particular, one currently…

The largest galaxies in the Universe reside in galaxy clusters. Using sensitive observations of carbon-monoxide, we show that the Spiderweb Galaxy -a massive galaxy in a distant protocluster- is forming from a large reservoir of molecular…

Within the NUclei of GAlaxies project we have obtained IRAM PdBI and 30m 12CO(1-0) and 12CO(2-1) observations of the spiral galaxy NGC 6951. Previous work shows that there is indirect evidence of gas inflow from 3 kpc down to small radii: a…

The extended nebulae formed as pulsar winds expand into their surroundings provide information about the composition of the winds, the injection history from the host pulsar, and the material into which the nebulae are expanding.…

In the last few years new evidence has been presented for the presence of ongoing massive star formation in the outer HI disks of galaxies. These discoveries strongly suggest that precursor molecular gas must also be present in some…

Assessing the origin of Pluto and Triton has profound implications for the bigger picture of Solar System formation and evolution. In such a context, this chapter reviews our current knowledge of the formation conditions of Pluto and…

The elemental composition of the gas and dust in a protoplanetary disk influences the compositions of the planets that form in it. We use the Molecules with ALMA at Planet-forming Scales (MAPS) data to constrain the elemental composition of…

Protoplanetary disks composed of dust and gas are ubiquitous around young stars and are commonly recognized as nurseries of planetary systems. Their lifetime, appearance, and structure are determined by an interplay between stellar…

Nearby galaxies exhibit a variety of structures, including central rings, similar to the MW Central Molecular Zone (CMZ). These rings are common in barred galaxies and can be gas-rich and highly star-forming. We aim to study molecular gas…

Recent ROSAT and ASCA X-ray observations as well as HST images have provided new insights into the structure and evolution of the 30 Dor nebula. I review hot gas properties of the nebula and discuss related physical processes. The structure…

In 1997 Soker laid out a framework for understanding the formation and shaping of planetary nebulae (PN). Starting from the assumption that non-spherical PN cannot be formed by single stars, he linked PN morphologies to the binary…

Planetary nebulae have been used as tracers of light and kinematics for the stellar populations in early-type galaxies since more than twenty years. Several empirical properties have surfaced: for example the invariant bright cut-off of the…

We investigate the process of galaxy formation as can be observed in the only currently forming galaxies -- the so-called Tidal Dwarf Galaxies, hereafter TDGs -- through observations of the molecular gas detected via its CO (Carbon…

We present early results from our program of ALMA Band 6 (1.3mm) molecular line mapping of a sample of nearby, well-studied examples of high-excitation, bipolar/pinched-waist and molecule-rich planetary nebulae (Hubble 5 and NGC 2440, 2818,…