Christmas Tree Cluster & Cone Nebula. The dark "V" shape above the top star in the Christmas tree is the Cone Nebula.
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New Moon: Wednesday, Feb 6.
Club Indoor Meeting: Thursday, Feb 7.
STAR GAZE (Feb 1):
Sun: Sets at 5:56pm and rises the next morning at 7:30am.
Between astronomical twilights.
Moon: (illuminated 24%) The Moon rises at 3:18am on the morning of Feb
2.
Satellites: You can check for satellite passes by
going to "www.heavens-above.com"
and logging-on as registered user "Astro Asheville" with password
"12345". There are several observing site to choose from. Choosing
the correct site is important only for seeing the Iridium flares.
DEEP SKY OBJECTS (DSO's) (Not the biggest or brightest, but interesting):
Open Clusters:
There are several open clusters to be discovered thru binoculars between
Sirius and Procyon: M41, M46, M47, M48, M50. M46 & M47 are very close together
in the sky but appear very different from one another. They have been described
as "The Rock and the Flower", and you can tell which is which when you
see them!
NGC 2264 (The Christmas Tree Cluster): Mag 3.9,
20' in size. Visible in binoculars, it is 3,000 light years away, or about twice
as far as the Orion Association. The brightest star in the cluster is at the base
of the tree, and the "top light on the tree" is immediately below (north
of) the difficult-to-see Cone Nebula. A large (18") telescope with a UHC
or OIII filter should be able to make out the Cone Nebula under dark skies. As
shown below on the right, in long-exposure images this nebula resembles Madonna
(seen from behind, complete with halo), holding baby Jesus in her arms. (Location:
6hr 41m RA +09 deg 53' Dec, in Monoceros)
Christmas
Tree Cluster & Cone Nebula. The dark "V" shape above the top star
in the Christmas tree is the Cone Nebula.
Nebulae:
NGC 2261 (Hubble's Variable Nebula): Mag 10.0, 2'x1' in size,
but varies in brightness, size, and detail due to the variable star that illuminates
the nebula. The variation is probably due to dust blocking the light from the
central star, and casting shadows upon the glowing gases. According to Burhnam,
changes in detail have been noted as great as 1.0" in four days. This nebula
is only 1 degree southwest of the Cone Nebula, so if you've found that
nebula, this one is easy to find! (Location: 6h 39.2m R.A.
8 deg 44' Dec, in Monoceros)
(Atlas map (20"x12", 128K) showing Orion, Procyon, the Cone Nebula, and Hubble's Variable Nebula. Until you use your controls to zoom in and explore the map, it will probably appear with moire patters. This fine hardcover atlas by Wil Tirion is sold by both Sky & Telescope and Barnes & Noble.)
Double Stars:
Rigel: A bluish-white
& blue pair, 9" separation; Magnitudes 0.1 & 6.8. Their distance
from Earth is 900 light years, so they are much closer than the stars that actually
belong to the Orion Association (1500 light years), but they are much further
away than Castor (45 light years). If Rigel were as close as Sirius (8.7 light
years) it would be magnitude -10. That's almost as bright as a full moon! (Rigel
is the right, or west, knee of Orion, so its easy to find!) (Location:
5h 14.5m R.A. -8 deg 12' Dec)
Castor (Alpha Geminorum): a white & blue-white pair, 4" separation; Magnitudes 1.9 & 2.9. Their distance from Earth is 45 light years & mean apparent separation is only 90 a.u. (2.25x that of our sun and Pluto). The following chart shows Castor B's orbit around Castor A. The points on the ellipse show Castor B's location for the given year. A third star (at magnitude 9, 73" away at position angle 164 from the main pair) is also gravitationally bound to this group and has a 10,000 year orbit. In fact, each of the three members is a "spectroscopic double", making 6 members to this group. A very nice article about Castor: Double Stars to Follow, Part II. (p.s.: Castor is the head of the Gemini twin on the right, Pollux is the one on the left, so it's easy to find!) (Location: 7h 34.3 m R.A. 31 deg 53' Dec)
(O degrees is north, 90 degrees is east, 180 degrees is south, 270 degrees is
west.
This is the view orientation through a Newtonian reflector telescope.)
Just WOW!: Sirius's position against the stars (it's "proper motion") has changed almost 3/4 degree in the last 2000 years, or 1.5 times the width of the full moon. It is the second closest of the naked-eye stars, and is even thought to be part of the "Ursa Major Moving Group", which includes the Big Dipper's 5 middle stars. If Rigel were as close as Sirius, it would be magnitude -10.2. Sirius is the brightest dang star in the sky, so it's easy to find, below and to the left of Orion.
Highlights:
Candlemas or Groundhog Day (a cross-quarter day): Feb 2.
TERMS
AFOV=apparent field of view / AU=Astronomical
Unit, the average distance from the Sun to the Earth / dec=declination / EP=eye
piece / FOV=field of view / ISS=International Space Station / HST=Hubble Space
Telescope / ly=light year / mag=magnitude / ra=right ascension /
culminates=transits the meridian=when an object as at its highest point in the
sky / transit=passing in front of another object / ZHR=zenithal hourly rate
(basically, the most meteors 1 person could see in 1 hour under ideal conditions)
CLUB STARGAZE
You can check the AstroAsheville
Yahoo e-group [or call Tim @ 251-0040 or John @ 251-1933 (before 5:00) or
667-9268 (after 5:00)] for a go/no-go decision and to verify location.
CLUB MEETING
Indoor club meetings are usually the first Thursday of every
month, at 6 p.m. in the Sims
Group offices (230 Short Coxe Ave., Asheville, NC.)
Happy Starwatching! Dress Warmly! Blue Ridge Parkway Information
Line is 828-298-0398
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(Much of the above info is derived from Sky & Telescope magazine, Ottewell's
Astronomical Calendar, The Night Sky Observer's Guide, Burnam's Celestial Handbook,
Megastar 5.0, Planets202, Cartes du Ciel, the ol' Miller Planesphere, and a
little (very little) common sense.)
