(IAAC) J 900 (PK 194+02.1; PN G194.2+02.5) - 17.5" F/4.5

Observer: Yann POTHIER (France)
Your skill: advanced (many years)
Date and UT of observation: 28 December 1997, about 22h50 UT
Location & latitude: La Clapiere Obs. (France, latN44 40 00, longE06 27 36)
Site classification: rural, alt.1650m (5500ft)
Limiting magnitude (visual in UMi): 6.31 with indirect vision (5% of the tim=
Transparency (1 to 5 - best to worst): 1
Seeing (1 to 5 - best to worst): 3 (stellar stars until 180x)
Moon up (phase?): no
Instrument: Coulter 17.5" (445mm) F/4.5
Magnification: 400x
=46ilters used: OIII, UHC, Hbeta
Object: J 900 (PK 194+02.1; PN G194.2+02.5; Jonckheere 900; ARO 92)
Category: planetary nebula
Constellation: GEM
Object data: Vmag=3D11.7; dim.12"x10"; type IIIb+II; central star of
Vmag=3D16.26; discovered by Jonckeere in 1916; ELCAT: [OIII, 496+510nm] =3D =
x [Hbeta, 486nm].
RA/DE: 06h25.9m, +17=B047' (2000); Uranometria 137
Description: at 400x and OIII, small PN, round, quite bright, homogeneous
or with slighlty brighter center, with sharp edges; about 10" in diameter
(estimated on drawing); a mag13 star is nearly in contact with the nebula
on the S border and at low power it can give the impression of observing a
double star; UHC has a very good contrast gain, as well as OIII but Hbeta
has no effect.
I can provide a scanned drawing of J 900 to anyone who can read the binhex
encoding of Eudora (for Mac); just mail me to try
(ypothier@abi.snv.jussieu.fr), it works sometimes with other
Yann Pothier
11 impasse Canart, 75012 PARIS, FRANCE
To UNSUBSCRIBE from the 'netastrocatalog' lists, use the Web form at: