Object name: PK24+5.1

Designation(s): PK24+5.1,

This image takes me back into the depths of the Milky Way for both a planetary nebula and some nice dark nebulae. Not easy to find such a combination for my 0.2 square degree field of view.

PK 24+5.1/Minkowski 4-9 is a planetary nebula in Serpens Cauda on the edge of LDN 472. The dark nebula at the top of the frame is DOBASHI 0972. LDN 469 extends along the right edge of my image at the lower right corner. The dark cloud above it is DOBASHI 0962. Though usually LDN 472 is applied to it and DOBASHI 0972 while LDN 469\'s designation usually includes DOBASHI 0962 though their given sizes in the LDN catalog are insufficient for this as best as I can determine.

The distance to the planetary is rather vague as is the case with most planetaries. I found a rather wide range of values from 1.2 to 2.83 kpc (3,900 to 9,230 light-years). The most recent value seems to be 1.72 kpc (5,610 light-years). Plantetary distances are very difficult to determine. This link goes into why this is the case. http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?2004MNRAS.353..589P&data_type=PDF_HIGH&whole_paper=YES&type=PRINTER&filetype=.pdf . It would appear the dark nebulae are behind the planetary but I found nothing on their distances.

By the way, the L in LDN stands for Lynds (Beverly T. Lynds) who compiled a catalog of dark (LDN) and another of bright (LBN) nebulae in the early 60\'s by scouring the original Palomar Observatory Sky Survey plates taken with the observatories 48\" Schmidt camera.

For a great high resolution narrow band image of this nebula see Jim Shuder\'s image at: http://www.pbase.com/jshuder/image/136810005/original

14\" LX200R @ f/10, L=4x10\' RGB=2x10\', STL-11000XM, Paramount ME