I just posted an update to my online visual notes for the NGC and IC. Last September, at the last update, I had completed all (true) NGC objects visible from mid-northern latitudes, but were missing about 350 far southern deep sky objects. At two week-long star parties in Australia (http://ozsky.org/
) in the past year I had an opportunity to track down most of the remaining objects with just 34 left at this point.
Besides my visual descriptions, all objects have historical discovery information. All of these are available at Adventures in Deep Space (http://www.astronomy-mall.com/Adventures.In.Deep.Space/
) or at the NGC/IC Project (http://www.ngcicproject.org/
). Most NGC/IC objects have multiple observations using 8" to 48" scopes, though the majority are in the 18" range. The NGCs and ICs are sorted into numerical order and also include aliases, positions, magnitude, size, etc.
Here's the introduction --I began taking notes on the Messier objects using a 6" f/5 reflector in 1978 and three years later was exploring fainter NGCs with a 13.1" Odyssey I. The vast majority of my notes were made using a 17.5" f/4.5 homemade dob (1987-2002), an 18" f/4.3 Starmaster (2003-2011) and a 24" f/3.7 Starstructure (2012-2016 ). Nearly 300 NGCs have also been visually described using Jimi Lowrey's 48" gigantic dobsonian from west Texas. In general, you'll find multiple observations of many NGCs through with a variety of apertures, so details can be directly compared.
In 2014, I completed a 35-year project of observing every NGC north of -41° declination from northern California. Deep southern objects not visible from the U.S. have been observed with 18", 24" and 30" scopes during a number of weeklong trips to Australia and a 13" travel scope in Costa Rica. As a result, in 2016 I nearly finished completing the entire NGC (7840 entries). Still remaining are only 34 far southern galaxies that I'm hoping to observe next year in Australia.
All of the NGC/IC identifications have been checked for historical accuracy as part of the NGC/IC Project. At the end of my visual observations of each NGC, I've included historical discovery information such as the observer's name, date, telescope, and the original discovery descriptions. Modern catalogues discrepancies and errors are also discussed.
I want to acknowledge the investigative work of Dr. Harold Corwin and Dr. Wolfgang Steinicke, who I've communicated with for many years on a number of identification problems. Harold Corwin provides precise positions and extensive historical notes on thousands of NGC and IC objects at http://www.haroldcorwin.net/. Wolfgang Steinicke has biographical information on 172 NGC/IC astronomers, as well as a number of historically accurate catalogues in .xls format at http://www.klima-luft.de/steinicke/index_e.htm. For those interesting in learning more on the history of the NGC, I highly recommend Wolfgang's book "Observing and Cataloguing Nebulae and Star Clusters".
For an excellent resource for images (and more) of NGC objects, check out Courtney Seligman's Celestial Atlas (http://cseligman.com/text/atlas.htm