Herschel 400 Catalogue

The Herschel 400 catalogue is a subset of William Herschel's original deep sky catalogue of 2,500 deep sky objects, selected by Brenda F. Guzman (Branchett), Lydel Guzman, Paul Jones, James Morrison, Peggy Taylor and Sara Saey of the Ancient City Astronomy Club in St. Augustine, Florida, USA circa 1980. They decided to generate the list after reading a lettercite journal | last = Mullaney | first = James | title = Letter to Sky & Telescope | pages = 235 | publisher = Sky & Telescope | date = April 1976 | url = http://pqasb.pqarchiver.com/skyandtelescope/access/887262721.html?dids=887262721&FMT=CITE&FMTS=CITE&date=Apr+1976&author=James+Mullaney&desc=Letter | accessdate = 2006-08-24 | format = subscription required] published in Sky & Telescope by James Mullaney of Pittsburgh, Pennsylvania, USA.cite web | last = Branchett | first = Brenda | title = Herschel 400 Club | url = http://www.astroleague.org/al/obsclubs/herschel/hers400.html | accessdate = 2006-08-24] .

In this letter Mr. Mullaney suggested that William Herschel's original catalogue of 2,500 objects would be an excellent basis for deep sky object selection for amateur astronomers looking for a challenge after completing the Messier Catalogue.

The Herschel 400 is a subset of John Herschel's General Catalogue of Nebulae and Clusters published in 1864 of 5,000 objects, and hence also of the New General Catalogue.

The catalogue forms the bases of the [http://www.astroleague.org/al/obsclubs/herschel/hers400.html Astronomical Leagues Herschel 400 club] .

Vital statistics

* The catalogue contains 400 objects
* All objects are from the NGC
* All visible in mid northern latitudes (they were all observed by William from the UK)
* All visible in 150 mm (6") or larger telescopes

Distribution of Herschel 400 objects

Herschel 400 objects which are also Messier objects

The Herschel 400 contains a few objects which are currently considered to be part of the Messier catalogue. For example Messier never published M104 to M110cite book | last = Jones | first = Kenneth | title = Messier's Nebulae & Star Clusters | publisher = Cambridge University Press | date = 1991 | id = ISBN 0-521-37079-5] in his lifetime they were added in the 20th century, an explanation as to why this is appears below:

* M20 NGC 6514 Trifid Nebula
* M33 NGC 598 Triangulum Galaxy
* M47 NGC 2422
* M48 NGC 2548
* M61 NGC 4303
* M76 NGC 651 Little Dumbbell Nebula/Barbell Nebula/Cork Nebula
* M82 NGC 3034 Cigar Galaxy
* M91 NGC 4548
* NGC 5866 (One of the possible objects identified as M102)
* M104 NGC 4594 Sombrero Galaxy
* M105 NGC 3379
* M106 NGC 4258
* M107 NGC 6171
* M108 NGC 3556
* M109 NGC 3992
* M110 NGC 205

Why does the Herschel 400 contain Messier Objects?

This is explained in the words of Dave Branchett:

The H400 was born almost 30 years ago now out of the need for observers who had completed the Messier list and wanted another deep sky challenge. It's hard to imagine but back in the mid 1970s observers had a limited sources of information, there was the SAO star charts that plotted all NGC IC objects but didn't label them on the charts.

Norton's Star Atlas had gone through its last classic reprint appearing around 1970 and it contained a large number of Herschel objects but it was Becvar's Atlas Coeli that was the most popular to use at the time, even though it contained numerous atlas ommissions.

The RAS republished the original NGC and IC catalogues in 1971, Sulentic and Tifft published the RNGC in 1975 but it was Burnham's that stole the show with its three volume set it opened up new horizons for the observer.

Telescopic equipment was also limited at that time, there were a few big boys but they were few and far between. The largest scope I owned back then was an 8" open tube A&E reflector that was built like a tank and weighed a ton but performed miracles.

So with this in mind the decision to include objects in the H400 that Messier had also seen was twofold:

# It already gave those who had completed the Messier list a leg up on the H400.
# It was a big help in building a list that would contain 400 objects of which for the most part would be small faint and fuzzy.

I well recall the late Fr Lucian Kemble remarking on how refreshing it was to see a bright beautiful nebula after seeing so many faint fuzzies.

As time went on however it also became apparent that some people were not just looking at these objects they were observing them. This made some people go back and re-observe the Messier objects when they had completed the H400, some were even amazed to see Herschel objects in the same field as Messier objects having completely overlooked them the first time around, especially the galaxies in Virgo.

Herschel had the utmost respect for Messier and he tried whenever possible not to duplicate any object recorded by Messier. If the H400 were to be done today I have no doubt that the Messier objects would not be included for we have so much at our disposal today and the optical performance of telescopes and binoculars are far superior than they were 30 years ago.

Herschel 400 objects which are also Caldwell objects

The Herschel 400 catalogue pre dates the Caldwell catalogue. The Caldwell catalogue contains the following objects which are members of the Herschel 400cite book | last = O'Meara | first = Stephen James | title = The Caldwell Objects | publisher = Cambridge University Press | date = 2002 | id = ISBN 0-521-82796-5] :

Herschel 400 objects

Key

201-300

301-400

References

ee also

* Messier Catalogue
* Caldwell catalogue
* New General Catalogue (NGC)
* Index Catalogue (IC)
* Revised New General Catalogue (RNGC)
* Revised Index Catalogue (RIC)
*
*

External links

* [http://www.astroleague.org/al/obsclubs/herschel/hers400.html Astronomical Leagues Herschel 400 club]
* [http://www.seds.org/messier/xtra/similar/herschel.html SEDS Herschel 400 information]
* [http://www.seds.org/messier/xtra/similar/similar.html SEDS page on similar catalogues to Messier's]
* [http://www.ngcic.org/DSS/dss_H400.asp The Herschel 400 at the NGC/IC project]
* [http://www.saguaroastro.org/content/Herschel-400-objects.htm The Herschel 400 at the Saguaro Astronomy Club]
* [http://www.ngc891.com/modules.php?op=modload&name=Stars&file=constellation&catalogue=Herschel Interactive star chart of Herschel 400]