| NGC
2440 |
Planetary
Nebula
aka PN G234.8+02.4, PK 234-2.1, ARO 47, ESO 560-9
RA: 07h41m55.4s, Dec: -18°12'31" (2000) in Puppis
Magnitude: 11.5
Size: 1'
Mean Surface Br. 19.9 Mag/arcsecē
Minimum
requirements to detect: 6-inch telescope |
|
I think the planetary nebula NGC
2440 (NGC 2440, PNG 234.8+02.4, PK 234+02.1, ARO 47, ESO 560-9) is
one of the finest in the sky. Catalogs list it as a 10.8 magnitude
object a mere 16" in diameter. Like many planetary
nebulae, in small telescopes or at low magnification it appears as a
small, elongated blob. Hunting it down and finding it in such
instruments is a reward in itself. In larger instruments some of the
detail in the above image begins to appear, making this a fine
visual object. 
This
image from the DSS shows a 20' x 20' field around NGC 2440. North
is down and east is to the right.
 I
first observed NGC 2440 in my 18-inch in January 2000. I was a bit
surprised by how bright it appeared. It is brighter than the 11th
magnitude listed. The planetary was obviously non stellar at 100x
and appeared as a tiny smudge. The best view came at 425x, where it
appeared distinctly bipolar, as seen in my sketch on the left. At
the heart of the nebula is two bright knots that nearly touch. The
surrounding nebulosity stretches in the directions perpendicular to
a line between the knots, and is brighter and extends farther to one
side. This one's definitely going on my list favorites due to its
interesting structure.
This is the
view of the field in a 6-inch at 50x. North is up, east is
to the right.
 This image was obtained with the Hubble Space
Telescope. Don't expect it to look anything like this in
the telescope! At the center lies a newly formed, 17.5 magnitude
white dwarf star--the now bare core of the original star after
puffing its outer layers away to create the nebula.
|
Millennium
Star Atlas Vol I Chart 319
Sky Atlas 2000 Chart 12
Uranometria 2000 Vol II Chart 319
Uranometria 2nd Ed. Chart 153
Herald-Bobroff Astroatlas B-12 C-69 |
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