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(IAAC) Obj: NGC 2440 - Inst: TV-102 (102mm f/8.6 APO refractor)
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Observation Poster: Ron B[ee] <ronby@home.com>
Observer: Ron B[ee]
Your skills: Intermediate (some years)
Date/time of observation: 01/05/02 11:00PST
Location of site: 117h 9m W (Lat 32h 43m N, Elev 2000 ft)
Site classification: Exurban
Sky darkness: 5.0 <Limiting magnitude>
Seeing: 7 <1-10 Seeing Scale (10 best)>
Moon presence: None - moon not in sky
Instrument: TV-102 (102mm f/8.6 APO refractor)
Magnification: 22x, 30x, 60x, 110x, 146x, 220x, 293x, 356x, 440x
Filter(s): none
Object(s): NGC 2440
Category: Planetary nebula.
Class:
Constellation: Pup
Data: mag 11.0 size 1.2' x 42"
Position: RA : DEC :
Description:
Last stop tonight after M46/NGC 2438 and M47, was a mag 11 PN, NGC 2440.
Thinking this was just another typical PN, the TV-102 made an astounding
realization that seem to match an observation made from a 10" reflector!
(More on this later).
At 22x and 30x, the PN looked stellar. 60x showed it as an unfocused
nonstellar glow. As with many PN, the 8mm TV Radian PN killer (110x)
nailed it, looked elongated and formed a diamond of spade shape with
the stars SAO 153271, GSC 5984:1357, and a star that turned out to be a 3
star triplet (GSC 5984:1431, GSC 5984:543, GSC 5984:1059) at 146x. 146x
gave a better view with darker background, bright.
Here is where the realization began. At 220x (4mm Radian), I noticed a
brightening center and became uneven at 293x. Being still bright at 293x,
I pushed the magnification to 352x (5mm Tak LE + 2X Ultima Barlow). I then
noticed 2 bright knots in the center; PN is still very bright. Using my 4mm
Radian + barlow at 440x, the 2 bright knots became easier to see. I made
note to research this afterward.
After some research, I stumbled across one of my favorite web site.
http://www.skyhound.com/sh/archive/feb/NGC_2440.html
Note the observation made by the 10" reflector and the image of the
nebula! What I saw was probably 1/2 as bright as the image shown.
I was stunned as I was typing this up. How could the TV-102 light
cup have seen the 2 knots, and without filter at that?
Luis Arguelles, my favorite double star champion, recently wrote in
the Refractors eGroup that the 4" refractor may be all the scope
you'll ever need. The TV-102 Light Cup sure was for me tonight ;-)
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