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Object(s):
NGC 6543, IC 4677
Observer: Mark Birkmann
Description: NGC 6543 and IC 4677 (large and faint
at mag. 15.7) My notes from March 1998 read as
follows: NGC 6543 was bright blue green at lower
powers, turning mostly green at higher powers. The
central star was easily visible. The oval shape
was obvious at all powers but at 390x the southern edge
was seen to be irregular with a comma shaped projection.
Of interest was a dim, diffuse, hazy patch of
nebulousity about 60 seconds west of ngc 6543.
The nebulousity was about twice the diameter of the
planetary. It was near the apex of a triangle of
dim stars and about two thirds of the way to the nearest
bright field star to the west of ngc 6543.
7-10-99 This
object turned out to be IC 4677. On this night I not only noticed
the comma shaped
projection but also a cap on the opposite side of the
central round area of nebulousity of ngc 6543.
E.
E. Barnards original notes on NGC 6543 and IC 4677. (~750k)
This drawing is from 7-10-99
Object(s): NGC 40 Observer:
Mark Birkmann
Description: This large, bright pn was gray at all
powers. I noted small dark lanes on either side of the easily detected
mag 11.5 central star. The upper edge of the pn
was slightly brighter than the central regions and the lower edge was
much brighter. A faint field star marked the location
of a notch in the edge of the pn. The pn was brighter with the Orion
Ultrablock but I preferred the view without the filter
since the faint field star was no longer visible.
Description: A great deal of detail is visible in
this planetary. The best view was with the Orion Ultrablock, although
I did not have the OIII with me and it may have been
as good or better. I was struck by the way the nebula almost
appears to have two "central stars" since two stars within
the nebula are in the center of dark regions. The fainter of
the two is probably not associated with the nebula but
the very faint, thin rim located near this star appears to bulge
out slightly with this star near its radius of
curvature. Without the filter in place a very faint
star was seen in this faint area of nebulousity. Yann has noted that
the central star is actually a double star but I
was unaware of this and did not record it as being double
in my notes. I'll take a closer look at the central star next
time. Note: I have since observed this object
twice on nights of average seeing and not noticed the central
stars companion.
Object(s):
NGC 1514 Observer: Mark G.Birkmann
Description: This pn was fairly faint but responded
very well to the Ultrablock filter. My first impression
with the filter in place was that this pn was almost
square rather than round. The central star was bright.
The central area of nebulousity was slightly dimmer than
the outer bright ring. The outer ring formed two
arcs one of which went about half way around the nebula
and the other of which went about one third of
the way around. On the side
where the arcs had the greatest separation the edges
of the arcs were clearly
concave. Part of the central,
inner, edge of the smaller arc also had a concave
area. Faint wisps of
nebulousity extended off of each of the bright arcs
helping to give this nebula its squarish
shape. A very
faint star was seen immediately
off the edge of the larger arc.
Object:
NGC 1535 (PK 165-15.1; PN G206.4-40.5; ARO 22)
Observer: Yann POTHIER (France)
Description: at 312x and OIII, medium sized PN, very bright,
round with sharp edges (fuzzier
without filter); at 74x, brighter to the center; at 312x,
a central area only is brighter as in a typical
double-shell PN and the central star is faintly visible;
at 312x and OIII, this central area looks
slightly annular (the central star is nor more visible);
at 400x and OIII, this annular area looks
larger; at low power, the bluish tint is quite evident;
UHC gives a good contrast gain, OIII a very
good one and Hbeta degrades the view (only the central
area is left); a wratten 38A blue filter was
tried with no contrast gain but acting as the Hbeta and
leaving on the central part visible;
estimated diameter of about 63"x55", central area is
33"x28" because the all is slightly elongated
WSW-ENE; the central star of about mag14 is very difficult
to substract form the central ring.
Object(s):
NGC 1535 Observer: Mark G.Birkmann
Description: The nebula was an evenly illuminated
blue-green with a distinct central ring. The central star was very
bright and
a faint star was noted near the edge of the nebula.
Object:
NGC 2392 (PK 197+17.1; PN G197.8+17.3; ARO 24; clown nebula)
Description: at 312x, medium sized PN (large with filter),
bright and round; about 47" in diam. without
filter and 64" with OIII (estimated on drawing) because
of a weaker external corona seen at 312x and
OIII; a brighter central area is seen, a little oval,
about 30"x25" N-S; UHC provides a good contrast
gain and erases the central star, OIII gives a very good
contrast gain and the extended edges are
getting sharper; the nebula looks bluish at 45x; the
mag8.5 star is at 1.6'N from the central star.
Description: This beautiful pn showed a bright inner
ring surrounding the central star. The area inside the ring was
evenly illuminated and slightlydarker than the outer
halo. The lower part of the ring split for a short distance with
a dark area in the separation equal in brightness to
the nebulousity inside the main ring. The outer halo was about
3x the diameter of the inner ring. It was evenly
illuminated except for a bright area near the top and a some what
bright area on the right side. I have seen so many
photos of this object that the upper bright area may have been
coming from my memory rather than from my retina.
This doesn't explain the bright area on the right though, since
none of the photos I've seen show this to be a particularly
bright area.
Object:
NGC 2438 (PK 231+04.2; PN G231.8+04.1; ARO 46; Sa 2-13)
Observer: Yann POTHIER (France)
Description: at 312x, medium sized PN, of medium brightness,
round with quite sharp edges; estimated
to be 70" in diam., obviously annular (ring thickness
of 25"); a 45° section of the ring centered on the
NW is less contrasty than the rest; a central star of
mag14 is somewhat eccentric, halfway between
the geometric center and the inner WNW edge of the ring;
UHC provides a good contrast gain and OIII
a very good one; a mag12 star is 10" from the SE border;
this PN is located 6' to the N of M46's central
area.
Object:
NGC 2440 (PK 234+02.1; PN G234.8+02.4; ARO 47; Sa 2-14; bat nebula)
Description: at 312x, medium sized PN, very bright, oval
SW-NE, about 69"x38", with ill
defined adges; brighter towards the center, very small
and bright nucleus (smaller than 8");
a plume or elongated extension leaves the nucleus in
a ENE direction (28"x9"); UHC provides
a good contrast gain and OIII a very good one; at low
powers, a bluish tint is obvious; a mag14
star is 20" from the S edge; a mag8.5 star is 4' to the
E.
Object:
NGC 2452 (PK 243-01.1; PN G243.3-01.0; ARO 93; He2-4; Sa 2-16)
Description: at 400x and OIII, small to medium sized PN,
medium brightness, round and homogeneous;
estimated diameter of about 29"
(on drawing); UHC has a good contrast gain, OIII a very good one and
Hbeta has no effect; the PN is larger
through OIII filter; a mag14 star is just detached form the NW edge;
NGC 2453, an open cluster of 15-20
stars between mag11 and 13 with one of mag9 against the NW border,
stands 9' away.
Object:
NGC 2610 (PK 239+13.1; PN G239.6+13.9; ARO 64; Sa2-27)
Observer: Yann POTHIER (France)
Description: at 312x, small to medium PN, faint to medium
brightness, oval about 42"x38" in a SW-NE
axis, soft edges; seen at 45x without filter and even
at 620x; center very slightly fainter; OIII and UHC
filters are providing a small contrast gain [see ELCAT
data above]; well seen without filter; evident
greenish color; a mag13 is just outside the NNE border;
a mag7 star is at 3.1'NE.
Object:
NGC 3242 (PK 261-32.1; PN G261.0+32.0; ARO 4)
Observer: Yann POTHIER (France)
Description: at 145x, bright PN, medium sized (about 70"x49"
on drawing), oval in a NW-SE axis;
double-shell clearly seen, even without OIII filter;
central part is annular but the ring is pinched on the
SE side and has a brighter surface on the NW side; the
inner ring is only 45"x35"; no central star visible.
Object:
Messier 97, M 97, NGC 3587 (PK 148+57.1; PNG148.4+57.0; ARO 25, VV 59)
Observer: Yann POTHIER (France)
Your skill: advanced (many years)
Category: planetary nebula Constellation:
UMa Object data:
Vmag=9.9; Bmag=12.0; 203"x199" (209"
in IDB); type IIIa; central star of Vmag=16.1; discovered by
Mechain in 1781; ELCAT: [OIII,496+501nm]
= 12 x [Hbeta, 486nm]. RA/DE: 11h14.80m,
+55°01.0'
(2000.0) Date and
UT of observation: 15 August 1996, 22h45UT
Location & latitude: La Clapiere
Obs. (France, latN44 40 00, longE06
27 36) Site classification: rural, alt.1650m
(5500ft) Limiting
magnitude (visual in UMi): 6.2
Transparency (1 to 5 - best to worst): 1
Seeing (1 to 5 - best to
worst): 3.5 Moon up (phase?):
no Instrument: Coulter 445mm/17.5" F/4.5
Magnification: 145-312x
Filters used: OIII, UHC, Hbeta
Description: at 222x, large PN, round, bord quite sharp
with UHC or OIII but diffuse without filter or with
Hbeta; medium brightness, estimated on drawing to be
3.4' in diameter (205"); its center looks darker
thanks to the two owl's eyes, oriented WNW and ESE from
the very faint central star ob about mag15
(visible only at 312x without filter with great attention);
the "eyes" have a diameter of about 50"; a mag
12 star is 1' from the N border; both UHC and OIII provides
a very good contrast gain but Hbeta is of no
use, strongly reducing the nebula's size.
Object:
NGC 4361 (PK 294+43.1; PN G294.1+43.6; ARO 26, VV62)
Observer: Yann POTHIER (France)
Description: at 125x & OIII, medium to large PN, faint,
homogeneous with very slight brightness
increase towards the core, hard to tell if there is internal
details; diffuse borders and mag13 central
star easy to see; estimated diameter about 136".
Object(s): NGC 6886 Observer:
Mark Birkmann
Your skills: Intermediate (some years)
Date/time of observation: 7/9/99, 6:00 UT
Location of site: New Haven,
Missouri (Lat N 38, Elev ~700')
Site classification: Rural Sky darkness: 5 <1-10
Scale (10 best)> Seeing: 5 <1-
10 Seeing Scale (10 best)>
Moon presence: None Instrument:
30" f/4, dob Magnification: 150x 540x
Filter(s): Orion Ultrablock
Category: Planetary nebula. Class:
2+3 Constellation: sagitta
Data: mag 12.2p
size 5.5" Position:
RA 20h:12m 42.8s DEC +19:59' 22"
Description: Very small, no detail, color, or central
star seen. Formed a triangle with two nearby stars, the nearest of
which was an obvious yellow.
Object(s):
NGC 7662 Observer: Mark Birkmann
Description: A bright "horseshoe" was seen in the
center and another
bright area was seen below the horseshoe. The
end of the horseshoe
opposite the open end appeared to be flattened.
The rest of the
nebula was fairly evenly illuminated except
that the center was slightly darker. The central
star was not seen at any power. The nebula was
greenish-blue at 257x, and bluish-green
at 470x. No filter was used.
