[sac-forum] Call for Observations
- From: "AJ Crayon" <acrayon@xxxxxxx>
- To: "SAC Forum" <sac-forum@xxxxxxxxxxxxx>
- Date: Tue, 27 May 2008 09:11:19 -0700
OK, it is time for the monthly reminder about observing some objects for the
SAC newsletter column. A 3rd constellation has been included in order to
attempt to keep ahead of the monsoon season. Perhaps for now we might call it
the windy season. Regardless, take a look at these, record what you see and
send it in. Please note the last constellation, Sagittarius hasn't been
published - yet. It will appear in the next newsletter issue.
The middle section of the Serpent, Hydra mostly made up of galaxies. The first
entry is 1.5° to the southeast of 5th magnitude SAO155588 and is the elliptical
NGC3091. Second is the almost round, barred spiral NGC3313, and at magnitude
11.4 is the faintest of the selections. Next is the almost edge-on spiral
NGC3717, is about 60' north of 5th magnitude SAO202553. Continuing the
eastward march is NGC3904 at magnitude 10.9. Then a scant 35' northeast is
NGC3923, which is the brightest of the selections at 9.8. Both of these
galaxies are elliptical. The final selection is the interacting pair NGC4105
and NGC4106.
The next month's selection will be Draco. There is quite a bit here to choose
from, especially since it crosses many lines of Right Ascension. Here we'll
keep to the region around the head of the dragon and find them all, save one,
galaxies. The magnitude range for the galaxies is 9.9 to 12th. The first
selection is NGC6140 a nice elongated barred spiral. Next jump is to NGC6340 a
nearly face-on early type spiral. There are other galaxies in the field. Can
you count and identify them? The Draco Dwarf, UGC10822 and a member of the
Local Group of Galaxies, is next and its magnitude is listed as 9.9. Beware
this can be misleading because its size is 33.5'X18. 9'and that gives it a low
surface brightness. You might try to ferret out some detail with averted
vision while waiting for a moment of good seeing. Continuing on our way finds
NGC6412 a barred spiral with some detail. Again, try to get as much out of
this one as you can. Our last galaxy is NGC6654, at 12th mag. Not clear, to
me, if it has some faint stars involved or bright HII regions. What do you
think? Finally comes an asterism named after Fr. Lucian Kemble called Kemble 2
and located at RA 18h35.0m Dec +72° 23'. It is 7th mag, 30' and forms a
''Mini-Cassiopeia'' like asterism. Mag
Again, keeping an extra month ahead, puts us in September, because of the
monsoon we find Sagittarius up for its third appearance. Most of these will be
from the Messier catalog, but not all. We will keep with some of the
lesser-viewed globular clusters and save the more popular ones for another
time. Our search begins with M 69 that has stars from 14th to 16th mag. What
is smallest telescope that can see the well-resolved nature of this object? On
July 22, 1995 just 15' west of southwest of where Comet Hale-Bopp was
discovered is the next selection - M 70. Still within the body of the Tea Pot
asterism is the very bright M 54. Now moving more towards the east is M 55,
the brightest globular cluster so far. Continuing to the northeast part of the
constellation is the planetary nebula NGC6818, often called the Little Gem
Nebula. Can you detect It's slight elongation of 22"X15"? The last entry is
nearby, NGC6822 also known as Barnard's Galaxy and a Member of the Local Group
of Galaxies. It has a surface brightness of mag 14.5 but is still viewable is
telescopes smaller than 8". Look for the bright HII region.
Happy Observing!!
AJ Crayon
Phoenix, AZ
Other related posts:
