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(IAAC) IC 418 - 22" F/3.9

To: netastrocatalog@atmob.org
Subject: (IAAC) IC 418 - 22" F/3.9
From: Yann Pothier <ypothier@closun.snv.jussieu.fr>
Date: Tue, 6 Jul 1999 17:19:00 +0200
Reply-To: netastrocatalog-announce@atmob.org
Sender: owner-netastrocatalog@atmob.org

Observer: Yann POTHIER (France)
Your skill: advanced (many years)
Object: IC 418 (PK 215-24.1; PN G215.2-24.2; ARO 3)
Category: planetary nebula
Constellation: LEP
Object data: Vmag=9.32; Bmag=10.7; 14"x11"; type IV; central star of
Vmag=10.17; discovered by Fleming in 1891; ELCAT: [OIII, 496+501nm] = 1 x
[Hbeta, 486nm] !!!.
RA/DE: 05h27.5m, -12°42' (2000)
Date and UT of observation: 20 November 1998, 23h00 UT
Location & latitude: Bellou-le-Trichard (France, latN48°16'08", longE
00°32'50")
Site classification: rural, alt.250m
Limiting magnitude (visual in UMi): 6.31 with averted vision (10% of the time)
Transparency (1 to 5 - best to worst): 1
Seeing (1 to 5 - best to worst): 1 (stellar stars until above 500x)
Moon up (phase?): no
Instrument: 22"/560mm F/3.9 (Torus optics)
Magnification: 629x
Filters used: none

Description: at 629x, delicate annular PN, elliptical, with a distinct
pinkish-reddish hue, faint central star (maybe mag13) which seems yellow by
contrast with the PN color [with no doubt, this reddish color is caused by
the faint OIII and Hbeta fluxes compared to Halpha's: Ha = 4 x Hb].




Yann Pothier
11 impasse Canart, 75012 PARIS, FRANCE
ypothier@abi.snv.jussieu.fr
ypothier@closun.snv.jussieu.fr
http://www.astrosurf.org/cielextreme
http://www.astrosurf.com/cielextreme
http://astrosurf.org/skylink/publi/cielextreme,


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