SIERRA STAR GAZERS

Observations for the June 15th Star Party

SSG Coordinators will be at the conveniently located Magnolia Ranch Trailhead observing site on Highway 49 at 8:00 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 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.

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 beverage 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 for the evening– Nicole Gauthier

Constellations

Tonight we’ll be observing objects in the constellations Ursa Major, Canes Venatici, and Scorpius, magnificent Saturn, and diminutive Mars. Let’s do the planets first.

Observing Saturn

Saturn is shining overhead at magnitude +0.6 this week at a distance 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 Mars

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 along 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 million 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 1/20th 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 tough object for smaller scopes. Beginning at Merak, slide your scope slightly below the imaginary line about 1/5th 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 dark 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 this 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.

Messier 51 is an 8th 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 call 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 mental 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 8th magnitude, this compact fuzzy is a fairly easy catch. The bright core is complemented by what appears to be a slightly dimmer ring of material surrounding 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 can 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 5th magnitude globular cluster. Located only 6,800 light years away, it is about 70 light years in diameter and about 10 billion years of age. 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 (s) Scorpii. Situated between the two stars and just to the south is our target. Use a bit of magnification to 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 constellations 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