Christmas Tree Cluster & Cone Nebula. The dark "V" shape above the top star in the Christmas tree is the Cone Nebula.
Full Moon:
Feb 6
New Moon:
Feb 20
STAR GAZE (Feb 20):
Sun: Sets at 6:18pm, astronomical twilight ends at 7:40pm
and begins at 5:46am the next morning. The Sun rises the next morning at 7:13am.
Between astronomical twilights, we get about 10.1 hours of darkness.
Moon: (illuminated 1%) The Moon sets at 6:42pm.
Jupiter & it's moons: Jupiter rises at 7:19pm. No
Jovian moon events are visible tonight. Jupiter culminates (is highest in
the sky) at 1:41am. The Great Red Spot crosses Jupiter's meridian about 9:00pm.
Jovian moon Io reappears from occultation behind Jupiter at 2:20am.
Saturn: Saturn has already risen by sunset. It culminates
at 9:01pm. The "star" located about 2 ring-diameters away to the southwest
is really the moon Titan. This winter is great time to view Saturn. It reached
opposition on December 31 and the rings appear very tilted to our view, so Cassini's
Division and other ring features are visible.
Asteroids: Ceres (in Gemini) has already
risen by sunset on the night of the gaze. It culminates at 9:27pm. You can see
it in binoculars as a star-like object at magnitude 7.7.
Comet C/2002 T7: : Discovered on October 14 in Gemini, it is now located in Pisces at magnitude 7.5 and will be lost in the Sun's glare by March. Perihelion will be in April, but visible then only from the southern hemisphere. See Sky & Telescope article and MISAO map.
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.
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'x.1' 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, 24 second download time at 56Kbps) 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 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.
You can check the Yahoo group for
AstroAsheville (or call Tim @ 251-0040
or John @ 251-1933 x17 (before 5:00) or 667-9268 (after 5:00)) for a go/no-go
decision and to verify location.
CLUB MEETING:
The club meeting is the first Thursday of every month, at
6 p.m. at Sim’s
Group located at 230 Short Coxe Ave., Asheville, NC.
Happy Starwatching! Dress Warm!
Blue Ridge Parkway Information
Line is 828-298-0398
www.AstroAsheville.org
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THE BIG PICTURE: Each chart below covers a very wide area of sky, roughly from eastern horizon to western horizon. Constellations are green stick figures. The dividing line between constellations are dashed blue lines. The purpose is to show the large scale structure of the night sky: why certain types of objects are visible in certain areas of the sky.
1. Above: 6 hr
R.A. (passes overhead on winter evenings,as in January): OPEN CLUSTERS
in the sky north to south (Auriga to Pupis). Open Clusters are generally within
the arms of the galaxy and are roughly co-located with the Milky Way. They are
plotted as tan circles above. You are looking away from the center of the galaxy.
(Note: all types of objects are labeled, not just open clusters.)
2. Above: 12
hr R.A. (passes overhead on spring evenings; rises before sunrise in January)
GALAXIES in the sky north to south (Ursa Major to Virgo). They are plotted
as blue ovals in the chart above. At 9:00pm during mid-June, the Milky Way is
rising in the east. Just to the west of the zenith is the North Galactic Pole,
in the constellation Coma Berenices. In southwest Coma Berenices happens to
be the heart of the Local Supercluster of galaxies. Many of these galaxies are
visible in medium-sized telescopes.
3.
Above: 18 hr R.A. (passes overhead on summer evenings; not visible in
January): GLOBULAR CLUSTERS (yellow cross inside a circle) & PLANETARY
NEBULAE (blue circle in a cross) in the sky north to south (Cygnus to Sagittarius).
The lower-middle of this chart is towards the center of the Milky Way galaxy.
Charts created using Megastar
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(Much of the above info derived from Sky & Telescope and Astronomy magazines, Ottewell's Astronomical Calendar, The Night Sky Observer's Guide, Megastar 5.0, Planets202, the ol' Miller Planesphere, and a little (very little) common sense.)
