The IAC Catalog of Northern Galactic Planetary Nebulae

The IAC Morphological Catalog of Northern Galactic Planetary Nebulae


"The IAC Morphological Catalog of Northern Galactic Planetary Nebulae" is a CCD imaging catalog composed of 607 images of 243 Northern planetary nebulae larger than 4 arcsec. The images have been obtained through narrow-band filters centered on nebular emission lines ([O III] 5007 Å, H-alpha 6563 Å, and [N II] 6584 Å). The observations were made with the 2.56-m Nordic Optical Telescope (NOT) at Roque de los Muchachos Observatory, and with the 0.82-m IAC80 Telescope at Teide observatory, both operated by the Instituto de Astrofísica de Canarias.

The catalog includes 128 pages presenting all the observed planetary nebulae, reproduced as grey-scale images, ranged according to their galactic latitude. 32 planetary nebulae are also depicted in color, made by combining the monochromatic images. For some nebulae (including a mosaic of the Dumbbell Nebula, M 27), the color picture obtained is a tentative true color image. The book also includes 8 pages describing the work and giving an introduction to planetary nebulae, as well as 3 tables with the most significant parameters, such as the coordinates and the angular sizes, of these planetary nebulae.


The Morphological Classification of Planetary Nebulae

The degree of symmetry of the planetary nebulae gives an indication on how they have formed. Excluding the non-extended objects, there are five main morphological classes:

1. Round

The planetary nebula shape does not show a clear deviation from symmetry. Some examples are:


jpeg 61K
A 39 is, perhaps, the classical vision of a planetary nebula: round and with a bright, blue star in the center. Image in the [O III] 5007 Å emission line.

jpeg 50K
NGC 3587 (the Owl Nebula) is a round nebula with structure. This image is a tentative true-color picture.

jpeg 11K
M 2-2 is a round nebula which displays a multiple shell structure.

2. Elliptical

The planetary nebula have two axes of symmetry, but do not show a `waist'.


jpeg 42K
The central part of NGC 6720 (the Ring Nebula) is a good example of an elliptical planetary nebula. This image is a false-color image obtained combining images in the [O III] (blue), H-alpha (red), and [N II] (red) lines.

gif 110K
A CCD mosaic was needed to cover NGC 6853 (the Dumbbell Nebula) due to its size (16 arcmin). This image is a tentative true-color picture.

jpeg 20K
IC 1295 is a multiple shell elliptical planetary nebula. The prevalent blue color is due to the emission in the [O III] line. Note that, due to the different width of the transmission filters used, the stars in the field appears artificially red.

3. Bipolar

The planetary nebula have two axes of symmetry, like the ellipticals, but they also have lobes and a waist.


jpeg 11K
He 2-437 is a highly collimated bipolar planetary nebula. The color index is as in NGC 6720.

jpeg 19K
He 2-428 shows clearly the presence of a ring which presumably is collimating the outflow of material, forming the bipolar lobes. Color index as in NGC 6720.

4. Quadrupolar

With two pairs of lobes, oriented in different directions. They are the result of bipolar ejections in a precessing source.


jpeg 89K
M 2-46 and M 3-28 as viewed through a filter which isolates the [N II] 6584 Å emission line.

jpeg 70K

5. Point-Symmetric

These planetary nebulae have no symmetry axis, but their morphological components are symmetrical with respect to reflection through the center.


jpeg 5K
PC 19 and Pe 1-17 as viewed through a filter which isolates the [N II] 6584 Å emission line.

jpeg 34K

IAC Planetary Nebula Research Group


Page update by
Arturo Manchado
amt@iac.es
ASTRONOMICAL HIGHLIGHTS