Our current state of understanding of the planetary nebulae (PNe) phenomenon is reviewed in the context of modern stellar evolution and dynamical models. Also discussed are a number of new problems that have emerged as the result of recent space (x-ray, UV, optical, and infrared) observations. The roles of PNe in the chemical (atomic, molecular, and solid-state) enrichment of the galaxy and as tracers of the large scale structure of the Universe are also discussed.

To record the spectral lines of stars and nebulae, photographic photometry was routinely used in the early 1900s, to be later replaced by methods employing more advanced detectors. We review the progress of planetary nebular spectroscopic studies, i.e. from the early photographic photometry, through to the 1950s photoelectric scanner observations, and finally to recent charge-coupled-device spectroscopy.

We report on an unprecedented source of Planetary Nebulae (PN) discovered from AAO/UKST Hα survey images of the Southern Galactic Plane. A pristine region of PN discovery space is being sampled due to the excellent depth, coverage, resolution and uniformity of the Hα survey. Large numbers of new PN are being found (~1000 so far). They are typically more evolved, obscurred and of lower surface brightness than in most other surveys. The doubling of known PN should have a significant impact on many aspects of PN research.

We are combining images in the mid-infrared (from MSX, the US Midcourse Space Experiment) with those from the high resolution UKST/AAO Hα survey of the Galactic Plane to investigate the relationship between the mid-infrared (MIR) and optical emission line properties of candidate Planetary Nebulae (PN) discovered by the Hα survey. Preliminary results indicate that only 10–20% of likely bona fide PN have a counterpart detected in the MIR. By sharp contrast one can readily recognize pre-main- sequence objects and HII regions emitting Hα and largely embedded in dust by the simultaneous presence of 8.3 and 21.3-μm emission suggestive of dust spanning a variety of temperatures. The sharpest criteria for recognizing true PN appear to be optical morphology and spectra (particularly the presence of [OIII]), and, where detected, MIR characteristics.

We report on version 1.0 of the Edinburgh/AAO/Strasbourg catalogue of new and possible Planetary Nebulae (PN) distributed via cdrom at this meeting. We provide accurate positions, designations, images and other descriptive parameters for the PN. In future releases this will be supplemented by inclusion of spectra and related material such as line ratios, velocities etc.

The 900+ PN have been discovered solely from visual scrutiny of narrow-band exposures taken for the AAO/UKST H-alpha survey of the Southern Galactic Plane. Most have classic PN-type morphologies (i.e. bi-polar, rings, shells or ovals). SuperCOSMOS data will soon supersede our visual scanning but it proved an effective preliminary technique to identify candidate PN on the basis of morphology, isolation and identification as an H-alpha nebulosity. We already have confirmatory spectroscopy for ~ 700 objects. Much of our new sample are of very low surface brightness, with no obvious central star, and so have remained undetected in previous surveys. They are revealed here due to the excellent depth, resolution, coverage and uniformity of the H-alpha survey. Many PN are also well extended. The average angular size is 51″ with the median of 27″ but examples extend to several arcminutes. This may indicate many are in a highly evolved state where the central star has faded from easy optical detection and the nebula itself is dissipating into the ambient ISM. Large numbers of candidate PN have also been found in the Galactic Bulge region, most of which have been confirmed via UKST FLAIR/6dF MOS spectroscopy (Parker et al, in preparation and these proceedings).

By version 2.0 (release in 2002) we will have doubled the number of Galactic PN accrued from all sources over the last 75 years. This new catalogue should have a profound impact on many aspects of PN research.

At http://astro.u-strasbg.fr/~koppen/png/png.html you'll find the first release of an interactive version of the Strasbourg-ESO Catalogue of Galactic Planetary Nebulae by Acker et al. (1992). The observational data of 1185 planetary nebulae can be inspected in detail numerically. Any two properties can be plotted against each other, with interactive zooming, graphical marking of groups of nebulae with certain properties, and identification and display of the data of any individually selected object. Maps of the sky – as well as of the space of any two parameters – can be displayed for any third parameter. Nebulae may be selected according to their names or observed parameters. This interactive catalogue is an application of the JAVA applet CatPlot which also permits the user to read in one's own catalogue file and also display images and x–y plots (a detailed description may be found in the explanatory pages at http://astro.u-strasbg.fr/~koppen/catplot/CatPlotHelp.html).

We have discovered new Wolf-Rayet type and weak emission-lines nuclei of the planetary nebulae in the Galactic center.

H 2–12 (PN 004.5+06.8) is classified as a true or probable planetary nebula (Acker et al. 1992). We obtained narrow-band imagery and long-slit echelle spectra from several positions across H 2–12. It is shown that H 2–12 is associated with one of the brightest condensations located at the periphery of Kepler's SNR. Thus, H 2–12 should be noted as a misclassified PN.

Candidate central stars can be seen in some (≤10%) of the many (~1000) new planetary nebulae found during scans of the AAO/UKST Hα survey of the Milky Way (Parker et al. 2002). Spectroscopic observations have identified seven with Wolf-Rayet emission features, thereby adding significantly to the 56 [WR] central stars already known (Jeffery et al. 1996). Two of these are late-type stars – [WC8] and [WC9-10], and four are early-type around [WC4] or possibly [WO4]. Two of the early-type stars have unusual strong emission features near 4610Å which may be attributed to [N V] and could be indicative of enhanced nitrogen in their atmospheres and unusual stellar evolution. The seventh star is of the [WN] sequence and, if confirmed, would be the only known [WN] central star in the Galaxy. Its surrounding circular nebula has emission lines with expansion velocities exceeding 150 km/s suggesting that the object may not a conventional planetary nebula. The possibility that it is a Population I star with a ring nebula, although looking increasingly less likely, cannot be finally ruled out at this stage. Full details of the [WC] stars have been given by Morgan, Parker, & Russeil (2001) and Parker & Morgan (2002). The candidate [WN] star is described by Morgan & Parker (2002).

We present near-infrared photometry of a large sample of PNe and show that the IJK colours are a good tool to distinguish different classes of PNe, like nebulae around symbiotic Miras or IR-[WC] PNe from genuine PNe.

We did photo-ionization modelling of 10 new Planetary Nebulae within 2° of the Galactic Center. We found that these PNe would originate mainly from low mass, old, metal poor stars.

We describe an on-going observational study to characterize the PN population of the Galactic Bulge.

The Midcourse Space (MSX) Experiment (Price 1995) detected large numbers of point sources in the LMC at 8.28 μm (Egan et al. 2001). Near-infrared J H K L imaging and monitoring of the 504 MSX sources in a region of size 3° x 3.5° covering most of the LMC bar has been carried out. Spectra have been taken for most of the post-AGB stars and a selection of the AGB stars and red supergiants.

We present the results of the classification of newly discovered M-type variables obtained as part of an H-alpha survey of Galactic dark cloud regions.

We have analysed about 350 Hα CCD images of PNe in order to measure their angular diameters. 3 different methods were used for calculations. Results and comments on each method are presented.