Download Constellations - Sierra Star Gazers

SIERRA STAR GAZERS
Observations for September 14th Star Party
SSG Coordinators will be at the very dark Icehouse Observing Park (IHOP) observing
site, accessed from Highway 50, at 7:30 pm to assist observers with basic telescope
setup procedures, Newtonian mirror collimation, and basic polar alignment questions.
IHOP is an excellent medium-high altitude dark sky venue for quality group observing.
For directions to the Icehouse Observing Park, just refer to last page of this list.
Please turn off your headlights, park your vehicle and set up your instruments as
directed. Over the years the SSG Coordinators have made (and survived) just about
every setup and observing error possible, so don’t be afraid to ask questions.
Remember, if you are fortunate to have more than one eyepiece, always begin
observing each object with the least magnification possible.
If you don’t have a telescope at this time, come join us anyway. We enjoy sharing.
Late September at IHOP promises stable seeing coupled with dramatically cooler
evenings as soon as darkness falls. Experienced observers dress in layers and
ALWAYS wear a warm hat, preferably one that can cover the ears. A thermos of a hot
beverage is guaranteed to make your innards toasty and your time at the eyepiece
more memorable. Insect repellant is highly advisable.
Tonight we’re going to search out a few of the most colorful single and multiple stars in
the fall sky, some memorable open clusters, plus two nearby galaxies that will both
excite your imagination and tax your observing skills a bit.
SSG Lead Host – Forrest Lockhart
Constellations
Locate the constellations of Cassiopeia, Cepheus, Delphinus, Andromeda, Triangulum,
and Perseus by referring to the Pocket Sky Atlas page numbers shown.
Cassiopeia
(S&T Pocket Sky Atlas – Pg 1)
Cassiopeia (KAS-ee-uh-PEE-uh), the Queen. Is one of the so-called circumpolar
constellations, which means that it may be observed on any evening of the year. Look
for the obvious letter M, or W, floating opposite the Big Dipper, with Polaris in between.
Here we will find a beautiful, true binary star system & a pretty open cluster.
Eta (η) Cassiopeia is a true binary star system with an orbital period of 480
years. Located just 19 light years away, this binary provides an exceptional color
and brightness contrast. The two stars enjoy a generous separation of 13”,
making it an east pair for most any scope. The 3.5 magnitude primary is yellow,
while the 7.4 magnitude secondary glows as a ruddy orange. Eta Cass may be
found between the stars Alpha (α) and Gamma (γ) Cassiopeia.
Messier 103 is a loosely defined open cluster located about 1° northwest of
Delta () Cassiopeia. Situated about 8,100 light years away, M 103 may be
spotted with binos, but is best observed through a small scope at low
magnification. The cluster is noteworthy by its conifer-shaped star pattern.
Cepheus
(S&T Pocket Sky Atlas – pg 71, 73)
Cepheus (CEE-fee-us), the King, is another of the circumpolar constellations, which
means that it too may be observed any time of the year. Look for Cepheus between
Cassiopeia to the north and the constellations Cygnus and Lyra to the south.
Herschel’s Garnet Star , Mu () Cephei, is a 4th magnitude red supergiant that
has the distinction of being one of the largest and brightest stars in the known
galaxy. While too far for a good parallax distance calculation, Mu Cephei is
thought to be about 2400 light years away. With a radius 1,650 times larger than
our Sun’s, if placed in the center of our solar system the surface would extend
out to between the orbits of Jupiter and Saturn. The star is approaching the end
of its life, and the super hot core is now fusing helium to carbon. In a few million
years the star will explode as a supernova and, considering its mass, is likely to
form a stellar black hole. The reddish hue of Mu Cephei is very apparent, with a
stellar classification of M2. Try defocusing your scope a bit to accentuate the
reddish color. This trick works on most objects when searching out a hint of color.
Delphinus
(S&T Pocket Sky Atlas – pg 64)
Delphinus (del-FEE-nus) is a small constellation adjacent to Sagitta. To my eyes
Delphinus resembles a tiny pollywog swimming at the edge of the Milky Way. While
easily overlooked at first, this constellation is always fun to rediscover.
Gamma (γ) Delphini is an impressive visual double located about 100 light
years away. The Gamma pair represents the nose of the pollywog. Sporting a
generous separation of 9”, these stars shine at magnitudes of 4.4 and 5.0. The
slightly brighter primary star is a rich yellow color, and the secondary is described
by many as a pale lime green. What colors do you detect? When ferreting out
faint colors does averted vision help? Why?
Andromeda
(S&T Pocket Sky Atlas – pg 3)
Currently located midway between the meridian and the eastern horizon, the
constellation of Andromeda can be found just north of the great square of Pegasus.
Gamma (γ) Andromedae, commonly known as Almach, is one of the finest
multiple star systems in the firmament. While Gamma is actually a triple star
system, only two stars are observable through amateur scopes. The system is
about 380 light years away. The observable pair is so bright that the colors are
readily apparent is scopes of nearly any size. The 2.3 magnitude primary gleams
a rich orange, while the 5th magnitude secondary is seen as bluish green. Don’t
overlook this beauty.
Messier 31 is a magnificent spiral galaxy located only about 2.3 million light
years away. The galaxy is slightly larger than our Milky Way, with a diameter of
about 130,000 light years. While only the central core area is visible in smaller
scopes, the observer should look further afield for the faint glimmer of the two
satellite galaxies, Messier 32 and 110.
Triangulum
(S&T Pocket Sky Atlas – pg 2 & 3)
Located east of Andromeda is a triangular asterism that accurately represents the
constellation of Triangulum. Midway between Triangulum and Andromeda is another
galactic member of our local group of galaxies. Much smaller and fainter than M31, this
is a worthy quarry.
Messier 33 , commonly known as the Pinwheel Galaxy, is a 5.7 magnitude open
spiral galaxy seen in plan view. At a distance of about 2.3 million light years, M33
has a diameter of about 33,000 light years, about 1/3 the diameter of our Milky
Way, and only ¼ the diameter of M31. Under a very dark sky, hints of the major
spiral arm structure may be glimpsed with a quality 4” refractor, but with M33 size
(aperture) does matter. Once located, use averted vision to ferret out those arms.
This is an excellent training ground for training your eye/brain linkage. If you spot
the arms through a scope of any aperture, call out to the group.
Perseus
(S&T Pocket Sky Atlas – pg 1 & 2)
Just rising over the northeastern horizon is the constellation Perseus. Between Perseus
and Cassiopeia is found one the most interesting objects to be seen through a small to
medium aperture scope. The best thing is that it so easy to locate.
NGC 869 & 884, popularly known as the Double Cluster, are a pair of open star
clusters situated about 7,300 light years away. With visual magnitudes of 5.3 and
6.1 respectively, the pair was labeled as Caldwell 14 by Sir Patrick Moore, but
somehow missed a Messier designation. While either cluster could stand alone
as a noteworthy object, the pair, spanning two full Moon diameters is truly
breathtaking. Since low magnification is a must in order to see both clusters at
once, small to medium short-focus scopes are recommended. The easiest way to
locate the clusters is to consider the asterism of Cassiopeia as an M with one
lazy leg. Draw an imaginary line from the center of the lazy leg directly toward
Perseus and follow the line until the pair floats into view...and what a view it is.
Directions to IHOP2: Drive east on Highway 50 into the mountains. Exit Highway 50
onto Icehouse Road. Travel about 6.3 miles to Peavine Road. Turn left and drive about
0.5 miles to an open lot on the left. Carefully drive to the south side of the lot and park in
a line.
Forrest