RVAS Treated to an Insider’s View of the Large Synoptic ...lighted by a presentation by Matt...

Volume 26 – Number 9 September 2009

Roanoke ValleyAstronomical

SocietyNews About Amateur Astronomy

in Southwestern Virginia

RVAS NL – September 2009 – Pg. 1 of 20 Contined next page

RVAS Treated to an Insider’s View of the Large Synoptic Survey Telescope

By Rick Rader

While we stand amazed at the stunning photographs from todays giant telescopes, both land and space based, it is difficult sometimes to imagine the degree of cooperation, planning and programming that is behind those images and data.

The August meeting of the RVAS was high-lighted by a presentation by Matt Cleveland, a 2005 graduate of Roanoke College. Matt is now working with the University of Arizona in the IS section developing programs for data management, specifically for computed orbits of Near Earth Objects (NEOs) and Kuiper Belt Ob-jects (KBOs). The overarching program is the LSST, or Large Synoptic Survey Telescope.

The heart of the data gathering for this program will be the largest digital camera in the world. Taller and wider than our club’s largest member, it is 6’4 tall and gathers 3200 Megapixles at a time, gen-erating 30 Tera-bytes of data PER NIGHT. The goals are to examine the skies for “blink” objects: objects that can

Image of the full Moon super-imposed on the chip array, to illustrate the field of view.

RVAS NL – September 2009 – Pg. 2 of 20

be detected with six data points, indicating three separate arcs, which belies objects that are in motion through space. They are poten-tially lethal if their orbits happen to inter-sect with ours here on Earth. The detection is observed by both motion and brightness. A change in brightness could indicate a tumbling asteroid, much like the one that just impacted Jupiter on July 19. That asteroid is estimated to have been a few hundred meters across and the impact was enormous. Curiously enough, the impact was discovered and reported by a hobbyist in Australia named Anthony Wesley.

Anthony’s discovery was verified by the Gemini program which has a Southern Hemi-sphere telescope located in Northern Chile. The Cerro Pachon site there shares space with a 4.2M SOAR telescope, and in 2015, the LSST is to be partially operative with a target of full science in 2017 at that same location.

Matt’s job is hardly simple. He, along with hundreds of specialists with 29 other universities and organizations spread across the US and South America, only needs to write programs that will take all this information, disseminate it so that there is complete data with no lost “edges”, detect and calculate location, movement, distance and speed — then regather and disperse data for the scientific community to analyze. The potential of this particular program is to quantify and discover the very nature and properties of dark energy, plot potential convergences of NEOs and KBOs, and see ten billion light years back in time.

Matt has been with this project for a short time. The LSST started Design and De-velopment only four years ago, when Matt graduated from Roanoke College. His enthusi-asm for his very critical portion of this mission is indicative of those hundreds of professionals

that labor at tasks that seem impossibly dif-ficult, but which both enrich and protect all of us. While we, indeed, stand on the shoulders of the giants that have gone before us, it is a delight to see our children grow up to be the next generation of giants.

For a very detailed view of the LSST, go to the project’s home page. You will find the second two images in this article among many more, including videos. Their site is http://www.lsst.org/lsst

Georges Robert Lezan, of Roanoke, Va., a member of RVAS, died at home suddenly on Sunday, August 23. Georges worked as an electrical engineer with General Electric from 1957 until his retirement in 1988. He was an avid amateur astronomer, lover of nature, inventor, tinkerer, and independent thinker. We will miss him.


Frank Baratta’s Astro-QuizWhat is the maximum number of first magnitude stars that can be seen above the horizon at one time at night from our latitude, what are the stars and when does this occur?

Answer to Last Month’s Astro-Quiz: Last month, we asked whether binoculars with 70mm lenses and 25 power or 15 power would be a better choice for night sky viewing. While the extra magnification of the 25 power set may sound appealing, that set would not be a good choice for night sky viewing. Dividing the diameter of the objective lens (70mm) by the magnification (25) gives the size of the “exit pupil,” the diameter of the bundle of light rays entering the eye – 2.8mm in this case. The dark-adapted pupil of our eyes is usually 5mm or more, such that any exit pupil smaller than 4mm loses too much of the eye’s potential, and should be avoided.

For several years the annual RVAS picnic in September has been held in Franklin County just east of Rocky Mount. This year, Septem-ber 19th, we are going up Bent Mountain to the Apple Ridge Farm, where our GE observatory is also located. Here are directions:

From Roanoke: From VA 419, take US 221 South up Bent Mountain. Copper Hill is 16 miles from VA 419 and Cave Spring Corners (that’s Electric Road and Brambleton Avenue). At Cop-per Hill, turn right onto VA 796 (Copper Hill Road). Stay on paved road, cross bridge. At end of pavement, turn right at pond.

From Christiansburg: Follow South Franklin St. out of town. Franklin becomes VA 615 (Pi-lot Road), then VA 612 (High Rock Road), then Daniel’s Run (VA 660 and Rt 610). At US 221, turn left and go North approximately 3 miles. At Copper Hill, turn left onto VA 796 (Copper Hill Road). Stay on paved road, cross bridge. At end of pavement, turn right at pond.

Here is the Apple Ridge Farm site: http://www.appleridge.org/

Here is the site for our observatory: http://appleridge.org/news/index.php?option= com_content&task=view&id=38&Itemid=85

Arrival time will be on September 19th (Satur-day) after 4:00 p.m. Executive Committee (EC) chefs will already be there with hot dogs and hamburger patties ready to cook over charcoal. The club will provide drinks and utensils. Club members as before will bring a dish to share.

We will first gather in the field near the tennis courts. Chow time about 5:00 p.m. Afterwards will be door prizes around 6:00 p.m. That leaves some daylight for folks to set up their scopes and prepare for what we HOPE will be a fine night of seeing.

All the details haven’t been worked out, so we are asking volunteers to check with any EC member. The club will be posting road signs. Also, the club expects to offer rides for those who need it, from Kroger on Brambleton near Cave Springs Corner, at 3:30 ... IF members want this carpooling option. Contact the EC.

RVAS Annual Picnic is Set for Saturday, September 19th

The Roanoke Valley Astronomical Society is a membership organization of amateur astronomers dedicated to the pursuit of astronomical obsrvational and photographic activities. Meetings are held at 7:30 p.m. on the third Monday of each month, at the Center in the Square in downtown Roanoke, Virginia. Meetings are open to the public. Observing sessions are held one or two weekends a month at a dark-sky site. Yearly individual dues are $20.00. Family dues are $25.00. Student dues are $10.00. Articles, quotes, etc. published in the newsletter do not necessarily reflect the views of the RVAS or its editor.

RVAS web page: http://rvasclub.orgOfficers/Executive Committee/Editor

Randy Sowden, President ([email protected])John Goss, Vice President ([email protected])

Mary Crouch, Secretary ([email protected])Jeff Suhr, Treasurer ([email protected])

Mark Hodges, Immediate Past President ([email protected])Paul Caffrey, Past President ([email protected])

Dave Thomas, Member at Large ([email protected])Clark M. Thomas, RVAS Newsletter Editor ([email protected])


The annual conference of the Virginia Association of Astronomical Societies will be in Charlottesville on Saturday, September 12. Thank you to the Charlottesville Astronomical Society for hosting it. Registration is $13.

Several RVASers will be carpooling for camaraderie and to save gas. A bus is possible.

Talks will be given by people from CAS, UVa, NRAO and the Naval Research Laboratory. There will be a BBQ dinner and stargaze at the McCormik Observatory that evening.

http://www.cvilleastro.org/vaas/

Program Schedule:

9:00 - 9:15 Registration.9:15 - 9:25 Introductory remarks & welcome by Richard Drumm, CAS President.9:25 - 9:45 Speaker #1 - Steve Layman, The

Chandra Grant Outreach Program.9:45 - 10:45 Speaker #2 - Dr. Brian Mason of NRAO: “The Sunyaev-Zeldovich Effect: Shadows Cast By the Microwave Back ground”10:45 - 11:00 Break for vendors and stretching.11:00 - 12:00 Speaker #3 - Dr. Joseph Lazio, Naval Research Laboratory: “The Lunar Radio Array”12:00 - 1:00 Lunch at the nearby Observatory Hill Dining Hall.1:00 - 2:00 Speaker #4.2:00 - 2:15 Break for vendors and stretching.2:15 - 3:15 Speaker #5 - Dr. Mark Whittle of UVa: “Primal Scream: Sounds from the Embryonic Universe”3:15 - 3:30 Break for vendors and stretching.3:30 - 4:30 Speaker #6.4:30 - 5:00 Door Prizes and concluding remarks.5:30 - 12:00 BBQ Dinner and observing session with the historic 26” Clark refractor, McCormick Observatory.

VAAS Comes to Charlottesville September 12th


“The Open Cluster”2010 Astronomical Calendar: Special Price for League Members

The Astronomical League is pleased to announce a special offer for our members from the Universal Workshop, producers of Guy Ottewell’s popular Astronomical Calendar. They are making the 2010 edition of the Calendar available at a discounted price.

There are plenty of good reasons why it has been published for over thirty years. The 2010 edition will not disappoint! Packed throughout the Astronomical Calendar’s 84 pages are monthly sky charts; daily celestial highlights; charts, tables, and explanations of planetary movements; eclipse times and paths; and lunar occultation specifics. There are extensive descriptions of the year’s me-teor showers and periodic comets, as well. This calendar tells, in clear language, what events occur and when they happen.

League members can order this incredible compilation of the year’s celestial events for $19.95, shipping included. (It is normally priced at $24.95 with another $7 added for shipping.) Volume discounts (a minimum of 15 copies) for clubs are available. But, to take advantage of the free shipping offer, you must order by Friday, October 31 — and either use the special website, www.Universalworkshop.com/clubs.htm, or call 800-533-5083. The League’s special low price of $19.95 expires on December 31, 2009. Universalworkshop.com accepts Mastercard, Visa, Discover, American Express and PayPal.

Jupiter and Moon Shadows:Example of How RVAS Members Help Each Other

“On Thurs., Aug 27, 2009 at 8:13 AM, g.shadel <[email protected]> wrote:I watched this last night in both Orion 10-inch and Celestron 8-inch reflectors with 5mm and 6mm eyepieces, and saw two smaller dots which I think were the shadows of two moons projected onto the surface of Jupiter, and one larger shadow (which came later), and I think was the combined shadow of the two moons projected back to earth.

“Am I interpreting this right? I could only resolve one moon close in prior to the first shadow appearing on Jupiter. I had expected to see two close together. Seeing oscillated between ok and excellent.”

- Gregg Shadel

“From about 11 pm until 1 am the shadows of Ganymede and Europa were both projected on the planet at the same time. And both Ganymede and Europa were transiting the planet, and they were situated closely to each other. With the magnification you were using, you should have been able to see them all.

“Io was occulted by Jupiter at about 10, and remained hidden until about 12:45 a.m. I hope this helps!”

- John Goss


Mystery Moon Light Flashesby Dave Thomas

For hundreds of years brief flashes of light, and changes in brightness on the surface of the Moon, have been observed by people from varying locations on Earth. A group of monks in 1178 witnessed what was believed to be the impact of a large as-teroid or me-teorite on the surface of the Moon. Since 1178 there have been many reports, but few have been seen by more than one person. Only a few flashes have been photographed, until now.

Several theories have been put forth to explain the phenomena, referred to as “Transient Lunar Phenom-ena,” or “TLP”. Some say they are caused by a change in the reflective qualities of the lunar surface. Others say they are out gassing from the Moon’s interior. Another cause could be an electrostatic field gener-ated by movement of the lunar crust.

One phenomenon that has been well documented is the impact of small mete-orites onto the surface of the Moon. The Meteorite Environment Office, MEO, a NASA

initiative, has been monitor-ing the dark portion of the Moon when the visible surface is 10 to 55% illumi-nated.

The accompany-ing photo shows the same impact as seen by two separate telescopes at the Automated Lunar and Meteor Ob-servatory, Al-aMO, located at Marshall

Space Flight Center, Huntsville, Alabama.

The following URL has images and info about the program, including what is needed to make an individual contribution to the program:

http://www.nasa.gov/centers/marshall/news/lunar/photos.html


RVAS President Randy Sowden called the meeting to order at 7:35 p.m. Randy welcomed all guests at tonight’s meeting.

Observing Reports:• Paul Caffrey held a Perseid meteor watch at Smith Mountain Lake. Between 12 and 3 a.m., he counted 2 - 3 meteors every 5 minutes with plenty of bright meteors included. • Rick Rader observed in Botetourt from 10:30 p.m. through 12:20 a.m. He counted 28 meteors during that period.• Jiri Kolejka also saw a number of Perseid meteors.• Mark Hodges was in Michigan on a mineral expedition when he encountered extremely dark skies.• Ten RVAS members observed at Cahas on Saturday August 15. They helped Frank Baratta present conduct his Parks Department session.

ALCon 2009:John Goss briefly described his experience at ALCon in NYC ten days earlier. He saw an inter-esting talk on drawing images as seen through the eyepiece. David Levy was the keynote speaker and the presentation that he gave was excellent. Next year, ALCon will be in Tucson, AZ on June 25 and 26.

Coming Events:• Randy announced a great opportunity for the club to connect with the community by par-ticipating in “Music under the Stars” at the Gainsboro Library on August 27 from 7:30 to 10:00 p.m. Members are invited to help with telescope views of the Moon and Jupiter.

• VAAS 2009 (Virginia Association of Astro-nomical Societies) will be hosted by the Char-lottesville Astronomical Society on September 12. Amateurs from across the Commonwealth will gather for this all day event. The RVAS may organize a car pool for those people inter-ested in attending.

• RVAS Picnic will be at Apple Ridge Farm on September 19. More details will be provided at a later date.

• Wine, Moon, and Stars will be held at Virginia Mountain Vineyard on October 23.

• VAAS 2010 will be in Roanoke next year. We need to secure a venue and organize a planning committee. Any volunteers? It will be fun!

Dues: Please pay Jeff Suhr your annual dues if you have not do so already. They must be collected by the RVAS picnic (September 19).

Member News:Congratulations are in order for Clark Thomas, RVAS newsletter editor. He won 5th place in the very competitive national Astronomical League Mabel Sterns Newsletter Editor Award. Clark was recognized for the quality newsletter that he puts together every month.

Lunar Feature. Dave Thomas described the various Apollo landing sites and how to find them in his five minute lunar talk.

What’s Up? Paul Caffrey described the celes-tial events taking place in the next few weeks from locating bright planets, to tracing constel-lations such as Lyra, Hercules, and Delphinus, to viewing deep sky objects such as M57.

Constellation Hunter Club. Rick Rader dis-cussed the Constellation Hunter Club from the Astronomical League. This is a great way for people to start their explorations of the night sky. All the details can be found on the Astro-nomical League web site under the Observing Club page (astroleague.org).

Feature Presentation. Rick Rader introduced Matt Cleveland who is working on the comput-er analysis side of the Large Synoptic Survey Telescope project headquartered in Tucson.

RVAS Meeting Notes: Monday August 17, 2009


Jazz Under the Stars Becomes Jazz Under the Clouds

Some nights start out with a reasonable possibility of having a successful outreach event with clear skies. On other nights, it is mostly clear right until you set up, then a cloud moves to cover the part of the sky that you’re most interested in. Thursday August 27 at the Gainsboro Library was just such a cloudy night.

The Gainsboro Library invited the RVAS to be part of their “Jazz under the Stars” event. The jazz was there. The

people were there. The telescopes were there. But the stars, Moon and Jupiter were not. Or, at least, they were not there in full view of the crowd of thirty anxious telescope viewers.

Fortunately, resourceful RVASers found other targets almost as interesting as the ce-lestial ones for people to observe: the flashing beacon over Towers Mall, and the church stee-ple at St. Andrews along with various tree tops, street lights and roof lines!

As it turned out, the scopes themselves were the “star” attractions. Many people wanted to learn about them and more about the RVAS.

Thank you to Rand Bowden, Paul Caf-frey, Fred Davis, John Goss, Mark Hodges, Randy Sowden, Jeff Suhr, and Dave Thomas for their efforts at making “Jazz under the Stars” an enjoyable evening and a creatively successful outreach!


Asterisms, a Prequelby Jack Gross

This is part 1 of a 3-part article on asterisms. Next month we’ll look at my top ten classical asterisms. And, the following month we’ll investigate ten lesser known asterisms.

If your hobby is mineralogy, an asterism is a star-like optical phenomenon produced in some crystals by reflected or transmitted light, such as the star in a star sapphire. Or, if you are into strange punctuation marks, an asterism is three splat marks (asterisks) placed in trian-gular pattern to call attention to a passage.

However, in astronomy an asterism is an easily recog-nized pattern of stars seen in the night sky — which is not classified as an official con-stellation. The term comes from the Greek word for star, “aster”. How-ever, in ancient astronomical texts, aster was often used for a pattern of stars rather than for single stars. Aster could also refer to a planet, or to a conjunction of planets and stars. Perhaps this usage might be what was meant in the New Testament description of the Star (aster) of Bethlehem, which, if it was not a supernatural phenomenon, need not have been a single star. But, that’s another story.

Naming star patterns in the night sky probably dates back to the emergence of man-kind. Grouping stars into constellations is es-sentially arbitrary, and different cultures have had many different constellations. Without an “official” list of the constellations and the stars they include, there was really no difference between a constellation and an asterism. Any-one with imagination could arrange and name a grouping which might or might not be generally accepted. This odd problem was finally resolved in 1930 when the International Astronomical Union

(IAU) divided the sky into 88 of-ficial constella-tions with precise boundaries. The constellations we know today are not actually pat-terns of stars, as we usually think of them, but rath-er areas of the sky. Most any other imaginative grouping of stars is an asterism.

There are several types of astronomical asterisms, such as

classical asterisms, modern asterisms, naked-eye asterisms, binocular asterisms, and telescopic asterisms. They can be cataloged, published or even unpublished. And, as you may suspect, there are a lot of them.

Continued next page...


One published list, the Saguaro As-tronomy Club Asterisms Database (http://www.saguaroastro.org/content/downloads.htm), lists 113 of them. The editor of that list, Steve Coe, in his definition of asterisms calls them, ” ... fun groupings of stars that do not constitute an en-tire constellation; as a matter of fact some of these objects are on the border between mul-tiple constellations.”

And fun they are. For one thing they usually look like what they are called. No stretching of the imagination or magical mush-rooms is required to see the Coat hanger, the Heavenly G, the Backwards 5, or the Lucky 7. Also, most asterisms are guide signs pointing the way to other sky objects; and many also fit nicely into a well-chosen eyepiece, making observing them a pleasure.

One of these very large sky maps can be found in the winter sky. It is the asterism known as “the Heavenly G,” nine bright stars forming a G-shaped group. Seven of these stars are 1st magnitude: Aldebaran, Capella, Castor, Pollux, Procyon, Sirius, Rigel, Bellatrix and Be-telgeuse. Another famous asterism are the pointer stars in the Big Dipper (itself another asterism), which show the way to the pole star, and more. Because of its location in the head of Taurus, Aldebaran has historically been called “the Bull’s Eye”. But Aldebaran also appears to be brightest member of the Hyades, which is the nearest star cluster to us. At a distance of 151 light years, the group is roughly spherical, and contains 300 to 400 stars that share the same age, origin, chemical content, and motion through space. However, Aldebaran is merely located on our line of sight with the Hyades. It is actually an independent star, only 67 light years away, and it sits in front of the sprawl-ing Hyades star cluster. By the way, the Milky Way, nebulae, and star clusters don’t count as asterisms, but, with the inclusion of Aldebaran, it becomes a V-shaped asterism in Taurus.

Nebulae, those clouds of gas and dust that dot the galaxy, are clearly not aster-isms, because they are not composed of stars, dah. That rules out things like the Pelican and the Horsehead nebulae. Clusters are groups of stars that are physically related and gravita-tionally bound together as they move through the galaxy in the same direction and speed. They are great to view through a telescope, but they don’t count as asterisms either. So, cross off clusters - like the Pleiades and the Beehive from the list of asterisms. Even though the Southern Cross isn’t vis-ible way up here in Virginia, it isn’t an asterism any longer, even though it was once. In his 1603 catalog, Bayer created it from the hind legs of Centaurs. Crux was given constellation status in 1930, thereby mutilating the centaur. Suspicion has it that this was done by space aliens. While we are in the southern hemi-sphere, we have the unusual case of Argo - named for the ship on which Jason and the Argonauts sailed in search of the Golden Fleece. So here is the story. (No, I am not doing my-thology.) Argo Navis was a very large constel-lation in the southern sky that was divided into three separate constellations. In fact, Argo was largest of all of Ptolemy’s constellations. Start-ing with Lacaille in his Coelum Australe Stel-liferum (1763), it became common to refer to its various parts as the Keel, the Poop Deck, and the Sails.

In the 1930 IAU arrangement, Argo was deemed too darn big, and these old sectional asterisms were recognized as three official constellations - Carina, the Keel, Puppis the Poop Deck (you got to love that one), and Vella, the Sails. I hate to leave you down here in the southern skies, but I’ll be back next month with my pick of the Top Ten.

‘Till then keep lookin’ up and down. (I promise not to write that ever again, maybe.)


Imaging the Trifid Nebula, M20by Michael Good

Photographing southern objects is a challenge at the “Good” Observatory. I must wait for them to clear the trees about one hour before zenith — and then they duck back into the trees about two to three hours after zenith. Such is the case with my friend M20, the Trifid Nebula. This object is in my opinion one of the prettiest in the night sky.

On two hazy summer nights with poor transparency and average seeing I attempted to glean some photons from this celestial gem, using my 14” and the usual cast of characters. Much like our friend, the Orion Nebula, there is a challenge in dynamic brightness in this object. The central two stars as well as the bright star embedded in the reflection nebula both produce long blooming spikes even with only two-minute sub-exposures — yet the nebula wants LONG exposures to pick up the faint details in the surrounding field. The color gradients were es-pecially nasty with this object, and my process-

ing in the attached image will have to wait for my skill at Photoshop to increase yet again.

The art of astrophotography is how many DIFFERENT kinds of images you can obtain from the SAME set of data, depending on your skill with the processing. Such is the case here. I would have wanted more than the 48 minutes of color data I obtained (8x2 minutes for each color), but the 26x2 minutes of Luminosity in-cludes throwing out about 8 images where the seeing was simply too fuzzy (probably passing clouds).

Don’t get me wrong, the image looks nice when glanced quickly, but I have been staring at Adam Block’s image taken with a 20” RC, and am aware of how pretty this object can be. As usual, this image looks dramatically different on my two pc monitors, so the quality of its appearance depends on how each monitor is set up.


Where Perfect Temperatures Compensate for Less Than Perfect Transparency...

Summer Nights at Cahasby John Goss

It is always a treat showing people the celestial wonders of summer, especially the jewels of the summer Milky Way. On Satur-day August 15th the clouds stayed away and the temperatures remained warm, presenting a fun opportunity at the RVAS monthly observing site at milepost 139 on the Blue Ridge Parkway.

Member Frank Baratta held his Roanoke City Parks observing session that eve-ning, and the RVAS was all too happy to participate. Frank and nine oth-er club members introduced twenty-five new night sky enthusiasts to the mid-August early evening sky.

In his well-crafted and informative pro-gram, Frank directed everyone’s attention along the Milky Way from Scorpius to Cassiopeia. He then moved to the bright stars of the Summer Triangle before he proceeded to the Big Dipper with its two “pointer” stars aimed at the North Star.

When the telescopes were ready, people peered into the eyepieces to see innumerable stars within the band of the Milky Way. They saw first-hand the crowded spherical star cities of globular clusters, stellar nurseries within wispy nebulae, and the expanding gaseous

envelopes from dying stars. Each person had their own way of expressing “Wow!”

Jupiter, which reached opposition on the night before, was the commanding light in the sky. Through the scopes, everyone caught its

four large Galile-an moons all in a line, three to the planet’s west, one to its east. This scene was per-fect for introduc-ing people to the International Year of Astronomy.

Thank you to all the RVAS members who helped make this warm summer evening so very enjoyable!

M57, a summer delight. Image: Michael Good.

Jack Gross and David Thaler fine tune their scopes.


Autumn Sky Constellationsby Jiri Kolejka

Autumn is a favorite time for astrono-mers, because cooler autumn air is more trans-parent than summer air. Night temperatures are still tolerable, and the autumn night sky is full of shining beauty.

Look up at two bright jewels of our solar system: sparking white Venus near the pre-dawn SE horizon, and the shining sphere of Jupiter high in the post-twilight southern sky. Next, imagine them followed up by two myste-rious planets: Uranus in constellation Aquarius, and Neptune in Capricorn.

The Great Square of Pegasus and An-dromeda constellations are rising up to dominate the northern celestial hemisphere, surrounded by constellations Cassiopea, Cepheus, Perseus, Pisces, Aquarius, Capricorn and Cetus.

Notice the three bright stars of the “Summer Triangle”: Vega, Deneb and Altair. Soon they will begin descending toward the SW horizon, pushing ahead of them notable sum-mer constellations Hercules, Ophiuchus, Corona Borealis and Sagittarius.

Now, let us point at Deep Space Objects (DSO) you can look at with bare eyes, with binoculars, or with a small as-tronomical telescope during autumn nights:- Globular clusters (GC); eye catching balls of old stars- Open clusters (OC); loose concentrations of stars tied together by

gravity- Galaxies (GX) of all kind of shape; beautiful spiral face on, edge on, irregular- Elliptical galaxies; the results of past galaxy mergers- Galaxies in cataclysmic collisions- Planetary nebulas (PN); the remnants of dead stars- Reflection (RN) and Emission (EN) nebulas; the birthing places of new stars- Supernova remnants (RN) of gigantic star explosions

Alphabetical prefixes of general DSO catalogs:M = Messier catalog by a 17th century comet-chaser Charles Messier, contains 110 objects in numerical sequence of their discovery.NGC = New General Catalogue with nearly 3,000 objects initiated by John Herschel and published in 1880 by Johan Ludwig Dreyer.IC = Index Catalog contains several thousand more objects observable by larger telescopes.

Pegasus

M 15Algenib

Alpheratz

Markab

Enifalpha

eta

Scheat

7331

StephansQuintet

GC

GX

GX

beta


In Greek mythology Pegasus is the Winged Horse of Perseus.

12th largest of all 88 constellations, takes al-most 3% of celestial sphere space.

3 brightest stars of Pegasus combine with An-dromeda’s alpha star Alpheratz to form promi-nent asterism “The Great Square of Pegasus”.

Although big in size, Pegasus is almost devoid of DSOs for viewing by amateurs. Only two no-table DSOs:- M 15; very nice densely packed GC at dis-tance 33 Kly, core collapse, one of 4 GCs with nebulosity, many variable stars & pulsars, 5 deg W of Enif.- NGC 7331; medium size spiral GX at 48 Mly, near the boundary with Lacerta.

A large aperture telescope would also reveal “Stephan’s Quintet”, multiple GXs in a gigantic collision.

AndromedaIn Greek mythology the daughter of Cassiopea and Cepheus, rulers of Ethiopia, was chained to a rock in sacrifice to a brute Cetus, but saved by brave Perseus riding on his Winged Horse Pegasus.

The 19th largest constellation, seen through thinly populated space of Milky Way (MW) to-wards intergalactic space.

Not rich on DSOs except for several notable GXs: M 31; a magnificent GX of Local Group, visible by bare eyes, larger than MW, 2.5 Mly away and on collision course with MW expected in about 5By.M 32 and M 110 are smaller companion GXs to M31.NGC 891; faint edge-on (mag 11) GX near Al-mach, 30Mly away.NGC 7662; “Blue Snowball” PN (mag 9), looks

like an eye in Hubble images.

Alpheratzalpha

Mirach

M 31M 110

M 32

891

7662

PN

AlmachGX

Scheat Markab


Cassiopeia

Queen of Ethiopia, vane & boastful female, of-fended Nereids who called on Poseidon to trash Ethiopia by Cetus.

Cassiopeia is loaded with DSOs and OCs in par-ticular:M52; rich OC (6.9) near border with Cepheus, found by Messier in Sep. 1774.M103; triangular shape OC (mag 7.4) near Ruchbah, 8Kly, last M-object added by MessierNGC 663; OC (mag 7.1) brighter and richer than M103 but missed by Messier.NGC 7789; OC (mag 6.7) 3 deg SW of Caph, found by Caroline Herschel.NGC 457; OC (mag 6.4) at 9Kly, includes double star phi 37 with nebulosity.NGC 7635; “Bubble Nebula”, very faint EN near M52.NGC 281; “Packman Nebula”, faint PN east of Shedir.

CepheusKing of Ethiopia, father of AndromedaNot notable for interesting DSOs, but delta 27 is Cepheid variable star with regular period that correlates to absolute magnitude and lu-minosity and therefore tells star distance from earth.

NGC 7160; small bright condensed OC.NGC 7235; small scattered OC with little con-centration.NGC 6939; moderately large bright condensed OC.NGC 0040; bright PN (mag 10.7) with appear-ance of an Angel.Mu Cephei; “Garnet Star”, deep orange Cephei, 3Kly away, discovered by William Herschel.

Caph

IC289PN

Ruchbah

Shedir

Segin

alpha

281OC

M 52OC

M103OC

663OC

7789OC

457OC

7635EN

37

Alrai

Alderaminalpha

7235OC

7160OC

7789OC

0040

PN

Alfirk

7129OC

GarnetStar

6946GX

6939OC

delta27


Perseus

Slayer of Medusa and Andromeda’s hero with winged sandals made from Medusa’s blood.

Alpha star “Mirfak within cluster “Persei Moving Group”.Beta “Algol” eclipsing star with 2.8-day period, (2.1 to 3.3 mag).Eta 15 is beautiful color-contrast pair (golden-yellow & blue-white).

Perseus is constellation rich on DSOs:M 34; large bright OC (mag 5.2) with about 60 stars in area of full moon size, 1.4Kly away.M 76; “Little Dumbell Nebula” bowtie PN (mag 12), discovered by Mechain.NGC 1023; bright GX near boarder with An-dromeda, elongated w/lenticular halo.NGC 1499; “California Nebula”, large EN illumi-nated by Menkib, need H-Beta filter.NGC 1528; prominent OC (mag 6.4) with about 50 stars in arcs & ovals.

Triangulum

Represents Nile delta in Egyptian mythology.A small isosceles triangle with alpha star Moth-allah.

Two remarkable DSOs:M 33; “Triangulum Galaxy”, 3rd largest spiral face-on GX in the Local Group with (mag 6.0), gravitationally tied to M31, 2.6 Mly away, faint, air condition is excellent if M33 is visible by bare eyes.NGC 604; huge EN (1 Kly across) embedded in M33, active massive star birth region.

Algol

Mirfakalpha

869OC

M 76PN

1023GX

44Atik

beta28

15

76

884

M 34OC

Menkibxi

1499EN

1528OC

1342OC

eta

Mothallahalpha

4

M 33

GX

beta

9

6eta


Aries

Ram in Greek mythology.

Aries includes a small flat triangle asterism with alpha star Hamal.NGC 772; spiral GX with one only strong arm, 130 Mly away, 2 supernovas.

Pisces

Goddess Aphrodite and son Eros transformed themselves into 2 fish after Olympians sent Ty-phon after them because in Olympian war they sided with Titans.

Large ranked 14th inconspicuous V-shaped con-

stellation of dim stars.Alpha “Alrischa” at bottom is binary starGiant eta 99 star outshines alpha AlrishaPentagon shape “Circlet” asterism on right.

Devoid of DSOs, except for:M 74; large faint face-on spiral GX at 35 Mly, bright center with massive black hole, discov-ered by Pierre Mechain in 1780, active star formation region (H II),M74 is a difficult “Messier Marathon” object because it sets soon after sunset.

AquariusAncient constellation rise in sky precedes Nile flood, so important for Egyptians.A water bearer for Zeus in Greek mythology.

Faint star constellation with giant stars alpha star Sadalmelik and beta star Sadalsuud, both are 50-times the size of our Sun.

DSO notables:M 2; bright compact GC (mag 6.6), only 175 ly away, 150,000 stars, easy to find.M 72; most distant 53 Kly away loose GC (mag 9), ob-ject for a large telescope.M 73; tiny dim star aster-ism in triangle shape also known as “Messiers mis-take”.NGC 7009; “Saturn Nebula”. PN (mag 8), bluish oval re-sembling planet Saturn.NGC 7293; “Helix Nebula” PN (mag 7.5) closest to us at 650 ly, large apparent size, faint and difficult to

see without a narrowband or OIII filter.NGC 7184; spindle shape GX with bright core, 26 Kly away.

Hamalalpha

772GX

beta

57

41

Sheratan

Mesartimgama

48

5

9

Alrishaalpha

M 74GX

86

eta

Fumalbeta


CapricornusGod Pan warned Olympians during war with Titans about approach of monster Typhon sent by Taia (Mother earth). Pan partly submerged himself in Nile and transformed its bottom part into a fish.

One of the oldest dim medium size constella-tions. Alpha star Algedi.Deneb Algedi (Tail of the Kid) white sub-giant binary only 39 ly away.

Almost devoid of DSOs:M 30; medium bright concentrated OC with prominent arms of stars.South of Beta is tri-angle of lovely binary stars (mag 5 & 6).

Sadalmelikalpha

Sadalsundbeta

Albali

Skat

7293

PN

7009

PN

1528 OCM 72

GC

GX

7184

Algedialpha

Dabihbeta

M 30GC

DenebAlgedi

delta


Cetus

Sea monster for Greeks, whale for Arabs.

Alpha Mercar, beta Deneb Kaitos are 2nd mag-nitude stars.

Large size constellation rich with DSOs:M 77; large bright barred GX, active with mas-sive black hole and large halo, hard to see in “Messier Binocular” competition.NGC 936; moderately large GX is elusive be-cause of low brightness.NGC 246; “Scull Nebula”, large bright PN (mag 8.0) with Y-shaped asterism.Mira is a long period variable (332 days) with extraordinary magnitude change from 2.0 to 10.1.

DenebKaitos

beta

Merkaralpha

Mira

BatenKaitos

246

PN

M 77GX

936GX


Calendar of Eventsby Frank Baratta

MONTHLY MEETING: Annual RVAS Picnic and Star Party. Saturday, September 19th, 4:00 p.m., Apple Ridge Farm, Floyd County. Join us for an afternoon and evening of friends, food,fun, and (hopefully) stargazing!

RVAS WEEKEND OBSERVING SESSIONS: Observing sessions are held at Cahas Mountain Overlook, milepost 139 on the Blue Ridge Parkway, except for the Annual RVAS Picnic and Star Party on September 19th, which will be held at Apple Ridge Farm, Floyd County.

★ Friday and Saturday, 11th and 12th. Sunset is at 7:33 p.m. Astronomical twilight ends at 8:59 p.m. The Moon rises at 11:44 p.m. and 12:49 a.m. on the 12th.★ Friday and Saturday, 18th and 19th. Sunset is at 7:22 p.m. Astronomi-cal twilight ends at 8:49 p.m. The Moon sets at 7:04 and 7:34 p.m., respectively. (Note: The 19th is the Annual RVAS Picnic and Star Party.)

★ October Sessions: 9th and 10th; 16th and 17th

Other Programs:

ROANOKE CITY PARKS DEPT. PUBLIC STARGAZE: Saturday, September 12th, 8:30 p.m., Cahas Overlook, milepost 139, Blue Ridge Parkway. For City, County and other area residents; RVAS members welcome. Call 540-774-5651, for information. (Next session: October 17th, 7:30 p.m., Cahas Overlook.)

FRANKLIN COUNTY PARKS DEPT. PUBLIC STARGAZE: Next Session, Saturday, November 7th, 6:45 p.m.)

RVAS Treated to an Insider’s View of the Large Synoptic ...lighted by a presentation by Matt...

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