(IAAC) NGC 6804 - 17.5" F/4.5

Observer: Yann POTHIER (France)
Your skill: advanced (many years)
Object: NGC 6804 (PK 045-04.1; PN G045.7-04.5; ARO 34)
Category: planetary nebula
Constellation: AQL
Object data: Vmag=12.0; Bmag=12.2; 63"x50"; type IV+II; central star of
Vmag=14.23; discovered by Herschel (as a PN by Pease in 1917); ELCAT:
[OIII, 496+501nm] = 11 x [Hbeta, 486nm].
RA/DE: 19h31.60m, +0913.4' (2000.0)
Date and UT of observation: 06 July 1994, 22h45 UT
Location & latitude: La Clapiere Obs. (France, latN44 40 00, longE06 27 36)
Site classification: rural, alt.1650m (5500ft)
Limiting magnitude (visual in UMi): 6.0
Transparency (1 to 5 - best to worst): 1
Seeing (1 to 5 - best to worst): 3
Moon up (phase?): no
Instrument: Coulter 445mm/17.5" F/4.5
Magnification: 45-312x
Filters used: UHC, OIII

Description: at 145x, medium sized PN, faint, slightly annular with UHC and
OIII because the SW border is fainter than the center and periphery of the
object; more easily annular with UHC at 312x; the nebula is visible at 45x
as a little hazy patch; UHC and OIII filters are giving a good contrast
gain; at 87x, a mag14 is in the ring on the NE side; at 145x, the border
are ill-defined; at 312x, another internal star, more centered and fainter
(mag15) is 20"SW from the mag14 star; estimated diameter of 66" (on
drawing), width of the ring structure is 25" (crescent in shape).

I can provide a scanned drawing of NGC 6804 to anyone who can read the
binhex encoding of Eudora (for Mac); just mail me to try
(yann.pothier@fnac.net), it works quite often with other configurations...

Yann Pothier
11 impasse Canart, 75012 PARIS, FRANCE

To UNSUBSCRIBE from the 'netastrocatalog' lists, use the Web form at: