sponsored by psychohistorian.org

DOCdb

Deep Sky Observer's Companion – the online database

 

Welcome, guest!

If you've already registered, please log in,

or register an observer profile for added functionality.

List:

log in to manage your observing lists

 browse:

 

 position:

 

 next:

 

 options:

summary

rename

prune

trim

remove

close

copy

combine

plan

bookmark

load

new

delete

marathon

favourite!

Full database:

Entire DOCdb database of 18,816 objects.

 browse:

 position:

NGC 7822 (39 of 18,816)

 next:

oc gc pln bn dn gx gxcl ast aka lost

Object:

list

bookmark

finder chart

altitude today

altitude (year)

 search:

½°, , in DOCdb


Warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected the timezone 'UTC' for now, but please set date.timezone to select your timezone. in /home/yivumoo/public_html/show_object.php on line 167

show browsing

NGC 7822

NGC 7822, Ced 215, LBN 589, LBN 118.59+06.13, Sh 2-171, h 2302, GC 5051

RA: 00h 03m 6s
Dec: +67° 23′ 0″

Con: Cepheus
Ch: MSA:36, U2:15, SA:1

Ref: SIMBAD

(reference key)

Type: supernova remnant

Mag: B=?, V=?

Size: ?
PA: ?

History and Accurate Positions for the NGC/IC Objects (Corwin 2004)

NGC 7822. I wonder about JH's declination for this. He has only one observation of it, and places it quite definitely 1.5 degrees north of the center of a huge HII region that would match his description pretty well. Here is what he has to say about it:

The central part of what I am positive is an enormously large, but extremely faint nebulosity of a round figure, though I cannot trace its limits. The night exquisite. I swept often across it to be sure, but always recurred to the same place. No doubt but can never be seen but in the best state of air and sky. Diameter 10 arcmin +-.

Dreyer attached two notes to the object, one in NGC itself: "Not seen at Birr Castle in two observations. It is, however, far north of the Zenith, and the speculum may have tilted." In the 2nd IC, he says briefly, "40' diameter, many stars involved (Roberts, MN lxviii, 301)."

Roberts's description, from three 90-minute plates taken in 1901 and 1902, is clearly that of the large nebula south of JH's position. Roberts notes three pretty bright stars involved (BD +66 1675, 1676, and 1679) which make it quite clear that he thought N7822 to be the HII region. I'm puzzled, though, that neither he nor Dreyer mentioned the differing declinations. I also find JH's diameter estimate to be puzzling. Usually, a 10 arcmin diameter would rate a description of "vL", not "eeL".

Also, there is, centered just a few arcmin south of JH's place, a "wing" of the nebula that could possibly be the object that he saw. But it is fainter than the main part of the object. Perhaps the northern part happened to be in the sweep on that "exquisite" night, while the brighter central portion was passed over in another sweep on an average night. Whatever the case, this fainter wing is a possible candidate for N7822, also.

However, I'm going to follow Roberts and Dreyer in adopting the HII region as the object that JH probably described, and assume that his declination represents an error of some sort. So, it gets the colon, while the northern wing gets the question mark. I've put the position for the HII region midway between the latter two BD stars in Roberts's note.

The HII region, by the way, is Cederblad 214B. It is incorrectly listed as a reflection nebula in at least one catalogue, and various pieces of it have ended up with separate numbers in Lynds's catalogue of bright nebulae. See Dixon's "Master List" for a complete list of the various names.

Historical observations

John Herschel

This bright nebula was observed by Sir John Herschel, who described it as "a remarkable object, most extremely faint, most extremely large."

NGC/IC Dreyer (1888, 1895, 1908)

Dreyer notes: "Not seen at Birr Castle in two observations. It is, however, far north of the Zenith, and the speculum may have tilted."

Published comments

Cederblad, S. (1946) [VII/231]

Ced 215 (NGC 7822)

Position (1900): RA 23 59.6, Dec + 68 0

Star: Cl (Mp=6.0:, SpT=A0, ?)

Spectrum of nebula: continuous spectrum (observed)

Classification: Nebulous cluster (milky neb cover the clusters, eg NGC 1976)

Size: 60'x30'

Notes: "NGC 7822 = GC 5051 = h 2302. R. The coordinates and the description given by John Herschel must refer to the nebulous cluster containing the HD stars: +68 1423 = HD 225123, and +67 1588 = HD 224825. Compare (630) Pl 20. (114, 304, 631). "

Lynds, B.T. (1965)

(Astrophysical Journal Supplement, No 105, 1965) in her Catalogue of Bright Nebulae notes that this nebula is moderately bright, more prominent on the red POSS plate and has a maximum size of 20' x 4'.

Sulentic & Tifft (1973)

(Sulentic and Tifft 1973) notes that this is a diffuse nebula.

Photo index

by Jim Lucyk: Astronomy mag. 11/85 p49, Deep Sky #17 Wi86 p14, Vehrenberg's Atlas of DS Splendors (3ed) p11, Vehrenberg's Atlas of Galactic Neb-1 p1 & 2.

Modern observations

Brian Skiff

15cm - don't see any convincing neb @ 30x or 50x w/[OIII] or UHC. broad region

of *s centered ~15' SE of triangle of m7-9 *s plotted on U2000. grp is

45' diam, looks like abs hole. BS, 26Oct1992, Anderson Mesa.

Favourite lists

Lacaille's catalogue

The Messier objects

Dunlop's catalogue

The Bennett objects

The Caldwell list

Named DSOs

Object search

First search phrase

    and

Second search phrase

Type of object to include:

open cluster
globular cluster
planetary nebula
bright nebula
dark nebula
galaxy
galaxy cluster
asterism & stars
unverified/lost
nova

The Bug Report

DOCdb is still in beta-release.

Known issues, feature requests, and updates on bug fixes, are here:

> Bug Report

Feedback

Found a bug? Have a comment or suggestion to improve DOCdb? Please let us know!

> Contact us

Help!

DOCdb is a free online resource that exists to promote deep sky observing.

You could help by sharing your observations, writing an article, digitizing and proof-reading historical material, and more.

> Find out more

Everything on DOCdb.net is © 2004-2010 by Auke Slotegraaf, unless stated otherwise or if you can prove you have divine permission to use it. Before using material published here, please consult the Creative Commons Attribution-Non-Commercial-Share Alike 2.5 License. Some material on DOCdb is copyright the individual authors. If in doubt, don't reproduce. And that goes for having children, too. Please note that the recommended browser for DOCdb is Firefox 3.x. You may also get good results with K-Meleon. Good luck if you're using IE. A successful experience with other browsers, including Opera and Safari, may vary.