SIERRA STAR GAZERS

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15 Νοε 2013 (πριν από 3 χρόνια και 6 μήνες)

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SIERRA STAR GAZERS

Observations for

the June 15
th Star Party


SSG Coordinators will be at
the conveniently located

Magnolia Ranch Trailhead

obs
erving site on Highway 49 at 8:0
0 pm to assist observers with basic telescope setup
procedures, Newtonian mirror

collimation, and polar alignment questions. Magnolia
Ranch Trailhead is an excellent low altitude venue for quality observing while staying
relatively warm, with two porta
-
potties, AND the western side of the level lot is certified
HPF (Horse Poo Free)!



For directions to the Magnolia Ranch Trailhead
,

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
eve
ry 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.


June promises warm days with cool evenings that can result in great observing. Even
so, experienced observers dress in layers and ALWAYS wear a warm hat, preferably
one that can cover the ears. A thermos of a hot be
verage is guaranteed to make your
innards toasty and your time at the eyepiece more memorable. Insect repellant is
advisable.


There will be no Moon to brighten our sky

tonight
, so we hope to have good deep sky
results.
This will probably be our final low
altitude observing session for the season. The
venue for our event in July may be the much
-
awaited dark
-
skies of IHOP or possibly
another dark sky site of Coordinators Gene & Pat Grahek’s choosing.


SSG Lead Host f
or the evening


Nicole Gauthier


Constella
tions

Tonight we’ll be observing objects in the constellations Ur
sa Major, Canes Venatici,

and
S
corpius, magnificent Saturn, and diminutive Mars
.

Let’s do the planets first.


Observing Saturn

Saturn

is shining

overhead at magnitude +0.6

t
his week at a dist
ance of about 830

million miles from Earth.

The dominant feature is the ring structure, which is now at
a 12.5
°

tilt from edge
-
on to Earth. Look carefully for the Cassini Gap and the moon
Titan. Other moons may be visible to the careful eye.


Observing Ma
rs

Mars is found due west of Saturn, also shining at +0.6
°
. The tiny disk is about 7.0”

in
size
,

and

is

becoming smaller with each passing evening.

There is little to discern on
the disk, but compare the color to Arcturus
overhead
and
Antares rising in the

south
.


Ursa Major







(S&T Pocket Sky Atlas


pg. 32
-
33
)

Ursa Major, with its familiar Big Dipper asterism
,

has the distinction of being a
circumpolar constellation, therefore it is visible all year from our latitude
. The locations
of your targets

are easy to point out because they all lie a
long an imaginary line
between the lower dipper stars Merak, Beta (β Ursa Majoris)

and Phecda, Gamma (γ
Ursa Majoris)


Messier 108

is a

10th magnitude spiral galaxy that is

found along the line from
Merak, and slightly below it.
Because the galaxy is 46 m
illion light years away it has
a tiny major dimension of just 8 minutes of arc. However, due to the concentration of
light along its edgewise tilt, it is surprisingly bright on dark nights. Look for mottling
along the foreshortening arm structure. This is
a physically small galaxy, having only
1/20
th

the mass of our near neighbor, M31.


Messier 97

is a
diffuse planetary nebula, glowing faintly at magnitude 9.9.
However,
due to a diameter of 170 “, it can be a t
ough o
bject for smaller scopes. Beginning at
Me
rak, slide your scope slightly below the imaginary line about 1/5
th

of the way
toward Phecda. Known as the Owl Nebula, this remnant of the death of a type G star
such as our own appears of rather uniform brightness in smaller scopes, but will
reveal two da
rk owl’s eyes when viewed through medium to large instruments. The
Owl is about 1630 light years away.


Messier 109

is
a barred spiral galaxy about 55 million light years away.
From Merak,
run along the line to Phecda, then overrun the star a tad to find t
his neat little faint
fuzzy.
With a magnitude of 9.8 it is displays a bright central core and bar structure
and a hint of spiral arms.
If you see a faint halo surrounding the bar, you are indeed
seeing the spiral arms.



Canes Venatici






(S&T Pocket Sky

Atlas


Pg. 32)


The Hunting Dogs can be a difficult find for first
-
time observers but in a short time it will
become an easy
-
to
-
find friend. Look below the handle of the Big Dipper until you come
across two relatively faint stars. The brightest, Alpha
(α)
Canum Venaticorum,
commonly known as Cor Caroli, shines at magnitude 2.8. A few degrees North
-
Northwest is a dimmer companion, beta
(β)
Canum Venaticorum, commonly known as
Chara, glowing dimly at magnitude 4.26. Now we can star hop to our targets.


Me
ssier 51

is an 8
th

magnitude open face spiral galaxy about 50,000 light years
across and 15 million light years away. Commonly known as the Whirlpool Galaxy,
the core of M51 is an easy find for scopes of 100mm aperture or larger, however,
the spiral arms c
all for more aperture. The outstanding feature of this object is the
prominent arm extending out to neighboring galaxy NGC 5195. The question for you
is… does the arm of M51 actually connect to NGC 5195? Ask one of the
coordinators. To find M51, draw a men
tal line from Cor Caroli to the star Alkaid in
the dipper handle. From Alkaid, slide about ¼ of the way toward Cor and M51 will
float into view. Take some time to eke out every detail that you and your scope are
capable of seeing and don’t forget the value

of averted vision.


Messier 94

is an

open face spiral galaxy with tightly wrapped arms. Glowing softly at
8
th

magnitude, this compact fuzzy is a fairly easy catch. The bright core is
complemented by what appear
s

to be a slightly dimmer ring of material su
rrounding
it. To find this object, draw another line from Cor to Chara. Now bisect the line and
slide toward Alkaid. Due to its compact size and stellar core, M94 can be mistaken
for a star at first glance at low magnification. Once again, averted vision c
an work
wonders.

Once found, higher magnification can be a plus.



Scorpius








(
S&T Pocket SkyAtlas


pg. 56)

The familiar asterism of Scorpius is now climbing above the southern horizon, and with
it comes one of the easiest
-
to
-
locate

objects in the
Messier catalog. Begin your search
at prominent red giant Antares, the heart of the scorpion.


Messier 4

is a nearby 5
th

magnitude gl
obular cluster. Located only 6,8
00 light years
away, it is about 70 light years in diameter and about 10 billion years of a
ge. The
main obstacle to finding M4 is its close proximity to the glare of Antares. Begin at
Antares and move up the body to adjacent star Omicron (

) Scorpii. Situated
between the two stars and just to the south is our target. Use a bit of magnification t
o
glimpse a bright line of stars that appears to traverse the cluster. Prominent Messier
observer Stephen O’Meara likens it to the iris of a cat’s eye. Shout out if you see it.




NEXT MONTH

we will explore the magnificent emission nebulae of the southern
constellation
s of

Sagittarius

and Scorpius
. Be sure to bring your binoculars if you have
them. Rarely can we spend an entire evening
in one are of the sky, but we do so each

July

in celebration of such a grand display of glowing clouds of gas.



Magnolia Ranch Trailhead

This site is on Highway 49. If coming from Highway 80, just drive about 6.7 miles past
the traffic light in the town of Cool, and look for the
marked

‘MAGNOLIA RANCH
TRAILHEAD’

turnoff on the right.

If coming from Highway 50, look
for a
‘TRAILHEAD’

sign 3.6 miles west of the T
-
intersection of Hwy 49 and Lotus Road. If you have been to Cronan Ranch, finding this
new site is a cinch.

Forrest Lockhart

SSG Coordinator