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June 2010 Volume 16 Number 12 Page 1 Star Gazer News Newsletter of the Delmarva Stargazers www.delmarvastargazers.org Prez comments…for the last time as President of Delmarva Star Gazers Approximately twenty years ago the idea of an organization for a star gazing organization began to take shape – in my mind. I talked to people from other organizations such as Bucks-Mont Astronomical Society, Delaware Astronomi- cal Society, York County Astronomical Society, Astronomical League, and the Springfield Amateur Telescope Makers to learn about their organizations and the details of creating a new organization. The gestation period was approximately three years and early in 1993 Delmarva Star Gazers was formed. Since then we have grown…the membership has grown in numbers…actual head count and age. We have also grown in scope…from simple stargazing to successfully promoting star parties and mirror making weekends. The internet has provided a communication vehicle that links our members from long distances not possible when we were created. New equipment in the form of GoTo drives/mounts, larger mirrors, CCD cameras, auto guiders, extremely wide- field eyepieces, coma and color correctors, specialized filters…all at decreasing prices…have been pouring from suppli- ers. Our skies have become brighter with unnecessary light. However, we have been fortunate to have successfully cultivated relationships with state run facilities that have provided access to the few dark sky areas still available so that we have safe and free accessible viewing areas. An organization that is all volunteer is no better than it’s membership. This is where we have excelled. Our members are also our friends. I am continually amazed by the efforts and talents of each of you to make DSG the best amateur astronomy organization possible. It is your efforts, talents and vision that drive DSG. We are approaching the end of this fiscal year and the beginning of the next…so now is your opportunity to af- fect the direction of DSG for the coming year. I urge each of you to communicate your ideas to Jerry Truitt, our incoming President, Lyle Jones, our President-elect, and me, the Past President. We, along with you, want to make the next year the best year for Delmarva Star Gazers. Let’s approach next year with the idea that change is necessary and good for continued growth. I would also like to steal with pride a slogan from a former DuPont colleague…”Continuous improvement is better than postponed perfection”. That’s why we need your ideas to fuel the continuous improvement of DSG. See you June 1 at our new meeting place…Christiana Care’s Community Room in Smyrna. Don… Upcoming Events: Meeting ! June 1 st 7 PM SHWC Observing ! June 11 Th Dusk Equestrian Cntr Come to the June meeting for the Election and Installation of Club Officers for 2010-2011

Star Gazer News · More details were formalized at the April Meeting and the first issue of Star Gazer News was issued on May 1, 1993, with Doug Miller as editor. The August 1993

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June 2010 Volume 16 Number 12 Page 1

Star Gazer News Newsletter of the Delmarva Stargazers

www.delmarvastargazers.org Prez comments…for the last time as President of Delmarva Star Gazers Approximately twenty years ago the idea of an organization for a star gazing organization began to take shape – in my mind. I talked to people from other organizations such as Bucks-Mont Astronomical Society, Delaware Astronomi-cal Society, York County Astronomical Society, Astronomical League, and the Springfield Amateur Telescope Makers to learn about their organizations and the details of creating a new organization. The gestation period was approximately three years and early in 1993 Delmarva Star Gazers was formed. Since then we have grown…the membership has grown in numbers…actual head count and age. We have also grown in scope…from simple stargazing to successfully promoting star parties and mirror making weekends. The internet has provided a communication vehicle that links our members from long distances not possible when we were created. New equipment in the form of GoTo drives/mounts, larger mirrors, CCD cameras, auto guiders, extremely wide-field eyepieces, coma and color correctors, specialized filters…all at decreasing prices…have been pouring from suppli-ers. Our skies have become brighter with unnecessary light. However, we have been fortunate to have successfully cultivated relationships with state run facilities that have provided access to the few dark sky areas still available so that we have safe and free accessible viewing areas. An organization that is all volunteer is no better than it’s membership. This is where we have excelled. Our members are also our friends. I am continually amazed by the efforts and talents of each of you to make DSG the best amateur astronomy organization possible. It is your efforts, talents and vision that drive DSG. We are approaching the end of this fiscal year and the beginning of the next…so now is your opportunity to af-fect the direction of DSG for the coming year. I urge each of you to communicate your ideas to Jerry Truitt, our incoming President, Lyle Jones, our President-elect, and me, the Past President. We, along with you, want to make the next year the best year for Delmarva Star Gazers. Let’s approach next year with the idea that change is necessary and good for continued growth. I would also like to steal with pride a slogan from a former DuPont colleague…”Continuous improvement is better than postponed perfection”. That’s why we need your ideas to fuel the continuous improvement of DSG. See you June 1 at our new meeting place…Christiana Care’s Community Room in Smyrna. Don…

Upcoming Events: Meeting ! June 1st 7 PM SHWC Observing ! June 11Th Dusk Equestrian Cntr

Come to the June meeting for the

Election and Installation of Club Officers for 2010-2011

June 2010 Volume 16 Number 12 Page 2

A Look Back at the Beginning of ‘Star Gazer News’ Pj Riley This issue of Star Gazer News is the 192nd edition. That’s about 1536 pages. Roughly 770 sheets of paper. Think about it ― 16 years of discussions, comments, observations, photography, helpful information, and even “bac-o’-da-bus” reports. I wasn’t there in the beginning, I think, but I’m gonna try to give you a brief early history gleened from the ‘early’ issues. On March 26th, 1993, a group calling themselves “M13 Amateur Astronomers” held a meeting. Twenty people attended that first meeting, amongst them: Don Surles, Kathy (Apostolus) Sheldon, Doug Norton, Norman Todd, Doug Miller, and Lyle Jones. They decided to meet once a month in Dover for an informal meeting and to also meet at an ob-serving site near the new moon. That basic schedule has continued to this day. More details were formalized at the April Meeting and the first issue of Star Gazer News was issued on May 1, 1993, with Doug Miller as editor. The August 1993 edition included. for the first time, a skychart. Each issue the first year improves with style and content, with photos, constellation charts. Now, in case you haven’t noticed, the Stargazers like to eat. While there were no star parties that first year (the monthly observing sessions were called ‘star parties’ ) there was a holiday party that first year at a private residence.

By January that first year, the meeting were moved to the church in Smyrna. Membership grew to 28 by Febru-ary when our late friend Jim Acker joined the Stargazers.

Here’s a little trivia from the March 1994 issue: How did the Milky Way get it’s name? Here what Doug Miller had in that issue.

Now, with the first year winding down, about 20 people and 9 telescopes showed up at the monthly ob-serving session at Killens Pond. At that ‘party’, attendees found out that Don and Herman were out observing the night before and apparently got stuck in a creek. Somehow this was caused by a deer. After waking up a farmer in the early morning hours to tow them out, Don and Herman treated the farmer to a tour of the sky. The summer of ’94 brought a major event, astronomically speaking; Shoemaker-Levy 9. These comet frag-ments were watched for a week as they fell onto (into?) Jupiter. It was reported in the ‘News’ that 10 observers went to Killens Pond to watch S-L 9 fragment B hit Jupiter, but mostly they just fed the vampire mosquitoes. The club slowly grew, and it was decided that in the Spring of ’95, a 3-day event was held at Killens Pond—Star Gaze I. This proved to be so popular that the first No-Frills Star Party was scheduled for that September at Tuckahoe State Park. The Star Gazer News was published for 4 years by Doug Miller until May of ’97 when Frank Sheldon came on-board as a co-editor. Frank took over the production of this newsletter and continued as editor for 8 years. I took over for Frank in June of ’05. The Star Gazer News will continue, hopefully, with the support and contributions of the club’s members. Send your contributions (although cash would be nice, I prefer articles, photos, etc) to [email protected]

June 2010 Volume 16 Number 12 Page 3

Your 2009-2010 Officers Office Officer Phone email President Don Surles 302-653-9445 President-elect Jerry Truitt 410-885-3327 Secretary Michael Lecuyer 302-284-3734 Treasurer Kathy Sheldon 302-422-4695 Past President Tim Milligan 410-841-9853

Elagabalus…

How do you like that name? Would you name your child Elagabalus?

Don Surles Again, my southern Baptist education has been augmented by a little effort with Google. I ran across Bro Ela-gabalus while looking for some info on meteorites. Here is the story…may it add to your wealth of knowledge. You may want to create a new folder in your brain in which to store this nugget from antiquity. It seems Bro Elagabalus was actually born to a Roman noble family around 205AD. Born Varius Avitus Bas-sianus, he was Syrian on his mother's side, the son of Julia Soaemias and Sextus Varius Marcellus, and in his early youth he served as a priest of the god El-Gabal at his hometown, Emesa. Upon becoming emperor at the age of 14, he took the name Marcus Aurelius Antoninus Augustus, and was called Elagabalus only a long time after his death. Thanks to the many Roman gods he was not called Egalabalus whilst alive. Here’s how the plot unfolded…In 217, the Emperor Caracalla was assassinated and replaced by his Praetorian prefect, Marcus Opellius Macrinus. Caracalla's maternal aunt, Julia Maesa, successfully instigated a revolt among the Third Legion to have her eldest grandson, Varius Avitus Bassianus, aka Marcus Aurelius Antoninus Augustus, later known as Elagabalus, declared as emperor in his place. Macrinus was defeated on June 8, 218, at the Battle of Antioch, upon which Elagabalus, barely fourteen, years old, ascended to the imperial power and began a reign that was marred by infamous controversies. During his rule, Elagabalus showed a disregard for Roman religious traditions and sexual taboos. He replaced the traditional head of the Roman pantheon, Jupiter, with a lesser god, Deus Sol Invictus, and forced leading members of Rome's government to participate in religious rites celebrating this deity, which he personally led. Elagabalus was married as many as five times, lavished favors on courtiers popularly assumed to have been his homosexual lovers, and was reported to have prostituted himself in the imperial palace. His reputed behaviour infuriated the Praetorian Guard, the Senate and the common people alike. Amidst growing opposition, Elagabalus, only 18 years old, was assassinated in a latrine, and replaced by his cousin Alexander Severus on March 11, 222, in a plot formed by his grandmother, Julia Maesa, and disgruntled mem-bers of the Praetorian Guard. Note to young Roman emperors…beware of Grandmothers! Elagabalus developed a reputation among his contemporaries for extreme eccentricity, decadence, and zealotry which was likely exaggerated by his successors and political rivals This likely propaganda was passed on, and as a result, he was one of the most reviled Roman emperors to early historians. Oh! The meteorite connection…it seems there was a sacred black stone in Egalabalus’ hometown of Emesa in the temple of the Sun-god. When Bro Egalabalus left his hometown he absconded with the sacred stone…the stone was also known as the “monolith of Baal”. After becoming emperor he dressed the meteorite, put it in a chariot and per-sonally led an odd religious procession through the streets every year. “He placed the Sun-god in a chariot adorned with gold and jewels and brought him out from the city to the suburbs. A six-horse chariot bore the Sun-god. The horses were huge and white with expensive gold fittings and rich ornaments. No one held the reins and no one rode in the char-iot. The vehicle was escorted as if the Sun-god himself was the charioteer. Egalabalus ran backwards in front of the chariot, facing the god, and holding the horses’ reins. Since he was unable to see where he was going, his route was paved with gold dust to keep him from stumbling and his bodyguards supported him on each side to protect him from injury”. We don’t know ‘zactly what happened to the meteorite after Egalabalus’ death…it probably made it’s way back to Emesa. And if it was a Sun-god it was probably very happy to be far from Bro Egalabalus. So, now that we have revealed this nugget of Roman history where will you file it? The sources of information are Wikipedia and Bad Astronomy by Linda Zimmerman.

June 2010 Volume 16 Number 12 Page 4

Ancient Supernova Riddle, Solved Dr. Tony Phillips Australopithecus squinted at the blue African sky. He had never seen a star in broad daylight before, but he could see one today. Was it dangerous? He stared for a long time, puzzled, but nothing happened, and after a while he strode across the sa-vanna unconcerned. Millions of years later, we know better. That star was a supernova, one of many that exploded in our corner of the Milky Way around the Pliocene era of pre-humans. Australopithecus left no records; we know the explosions happened because their debris is still around. The solar system and everything else within about 300 light-years is surrounded by supernova exhaust—a haze of mil-lion-degree gas that permeates all of local space. Supernovas are dangerous things, and when one appears in the daytime sky, it is cause for alarm. How did Earth survive? Modern astronomers believe the blasts were too far away (albeit not by much) to zap our planet with le-thal amounts of radiation. Also, the Sun’s magnetic field has done a good job holding the hot gas at bay. In other words, we lucked out. The debris from those old explosions has the compelling power of a train wreck; astronomers have trouble tear-ing their eyes away. Over the years, they’ve thoroughly surveyed the wreckage and therein found a mystery—clouds of hydrogen and helium apparently too fragile to have survived the blasts. One of them, whimsically called “the Local Fluff,” is on the doorstep of the solar system. “The observed temperature and density of the Fluff do not provide enough pressure to resist the crushing action of the hot supernova gas around it,” says astronomer Merav Opher of George Mason University. “It makes us wonder, how can such a cloud exist?” NASA’s Voyager spacecraft may have found the answer. NASA's two Voyager probes have been racing out of the solar system for more than 30 years. They are now beyond the orbit of Pluto and on the verge of entering interstellar space. “The Voyagers are not actually inside the Local Fluff,” explains Opher. “But they are getting close and can sense what the cloud is like as they approach it.” And the answer is … “Magnetism,” says Opher. “Voyager data show that the Fluff is strongly magnetized with a field strength between 4 and 5 microgauss. This magnetic field can provide the pressure required to resist destruction.” If fluffy clouds of hydrogen can survive a supernova blast, maybe it’s not so surprising that we did, too. “Indeed, this is helping us understand how supernovas interact with their environment—and how destructive the blasts actually are,” says Opher. Maybe Australopithecus was on to something after all. Opher’s original research describing Voyager’s discovery of the magnetic field in the Local Fluff may be found in Nature, 462, 1036-1038 (24 December 2009). The Space Place has a new Amazing Fact page about the Voyagers’ Golden Records, with sample images and sounds of Earth. Just in case one of the Voyager’s ever meets up with ET, we will want to introduce ourselves. Visit http://spaceplace.nasa.gov/en/kids/voyager. This article was provided by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.

Left-over cloud from the Tycho supernova, witnessed by Tycho Brahe and other astronomers over 400 years ago. This image combines infrared light captured by the Spitzer Space Telescope with x-rays captured by the Chandra X-ray Observatory, plus visible light from the Calar Also Ob-servatory in Spain.

June 2010 Volume 16 Number 12 Page 5

Magazine Subscriptions As a paid member of DMSG, you can sign up/renew your S&T or Astronomy mags through the club for a discount over private rate. S&T, reg. $42.95, is $32.95 thru DMSG, Astronomy, reg. $44, is $34. See Michael Lecuyer for details.

COMETS Pj Riley All y’all know about Comets. They’re dirty ice balls orbiting the Sun. But what did people think comets were a century ago? Below is an excerpt from THE ASTRONOMY OF THE BIBLE

BY E. WALTER MAUNDER, F.R.A.S. (printed 1908)

Great comets are almost always unexpected visitors. There is only one great comet that we know has been seen more than once, and expect with reasonable certainty to see again. This is Halley's comet, which has been return-ing to a near approach to the sun at somewhat irregular intervals of seventy-five to seventy-eight years during the last centuries: indeed, it is possible that it was this comet that was coincident with the invasion of England by William the Conqueror. There are other small comets that are also regular inhabitants of the solar system; but, as with Halley's comet, so with these, two circumstances are to be borne in mind. First, that each successive revolution round the sun involves an increasing degradation of their brightness, since there is a manifest waste of their material at each near approach to the sun; until at length the comet is seen no more, not because it has left the warm precincts of the sun for the outer darkness, but because it has spent its substance. Halley's comet was not as brilliant or as impressive in 1835 as it was in 1759: in 1910 it may have become degraded to an appearance of quite the second order.

Next, we have no knowledge, no evidence, that any of these comets have always been members of the solar family. Some of them, indeed, we know were adopted into it by the influence of one or other of the greater planets: Ura-nus we know is responsible for the introduction of one, Jupiter of a considerable number. The vast majority of comets, great or small, seem to blunder into the solar system anyhow, anywhere, from any direction: they come within the attrac-tive influence of the sun; obey his laws whilst within that influence; make one close approach to him, passing rapidly across our sky; and then depart in an orbit which will never bring them to his neighbourhood again. Some chance of di-rection, some compelling influence of a planet that it may have approached, so modified the path of Halley's comet when it first entered the solar system, that it has remained a member ever since, and may so remain until it has ceased to be a comet at all.

It follows, therefore, that, as to the number of great comets that may be seen in any age, we can scarcely even apply the laws of probability. During the last couple of thousand years, since chronicles have been abundant, we know that many great comets have been seen. We may suppose, therefore, that during the preceding age, that in which the Scriptures were written, there were also many great comets seen, but we do not know. And most emphatically we are not able to say, from our knowledge of comets themselves and of their motions, that in the days of this or that writer a comet was flaming in the sky.

If a comet had been observed in those ages we might not recognize the description of it. Thus in the fourth year of the 101st Olympiad, the Greeks were startled by a celestial portent. They did not draw fine distinctions, and posterity might have remained ignorant that the terrifying object was possibly a comet, had not Aristotle, who saw it as a boy at Stagira, left a rather more scientifically worded description of it. It flared up from the sunset sky with a narrow definite tail running "like a road through the constellations." In recent times the great comet of 1843 may be mentioned as having exactly such an appearance.

So we cannot expect to find in the Scriptures definite and precise descriptions that we can recognize as those of comets. At the most we may find some expressions, some descriptions, that to us may seem appropriate to the forms and appearances of these objects, and we may therefore infer that the appearance of a comet may have suggested these descriptions or expressions.

The head of a great comet is brilliant, sometimes starlike. But its tail often takes on the most impressive appear-ance. Donati's comet, in 1858, assumed the most varied shapes—sometimes its tail was broad, with one bright and curving edge, the other fainter and finer, the whole making up a stupendous semi-circular blade-like object. Later, the tail was shaped like a scimitar, and later again, it assumed a duplex form.

Though the bulk of comets is huge, they contain extraordinarily little substance. Their heads must contain some solid matter, but it is probably in the form of a loose aggregation of stones enveloped in vaporous material. There is some reason to suppose that comets are apt to shed some of these stones as they travel along their paths, for the orbits of the meteors that cause some of our greatest "star showers" are coincident with the paths of comets that have been observed.

But it is not only by shedding its loose stones that a comet diminishes its bulk; it loses also through its tail. As the comet gets close to the sun its head becomes heated, and throws off concentric envelopes, much of which consists of

June 2010 Volume 16 Number 12 Page 6

The June Sky—From Half-Hours with the Stars (1911) RICHARD A. PROCTOR, F.R.A.S.

The Great Bear (Ursa Major) is in the mid-heavens toward the northwest, the Pointers not far from the horizontal position. They direct us to the Pole Star (α of the Little Bear, Ursa Minor). The line from this star to the Guardians of the Pole, β and γ, is in about the position of the minute hand of a clock 2 minutes before an hour. The Dragon (Draco) curls over the Little Bear, curving upward on the east, to where its head, high up in the northeast, is marked by the gleaming eyes, β and γ. Under the Little Bear, the Camelopard has at last come upright.

Low down in the west the Lion (Leo) is setting. The point of the "Sickle in the Lion" is turned toward the horizon; the handle (marked by α and η) is nearly horizontal. Above the Lion's tail is Berenice's Hair (Coma Berenices); and between that and the Great Bear's tail our chart shows a solitary star of the Hunting Dogs (Canes Venatici). The Crow (Corvus) is low down in the southwest, the Cup (Crater) beside it, partly set, on the right. Above is Virgo, the Virgin. Still higher in the southwest—in fact, with head close to the point overhead—is the Herdsman (Boötes), the Crown (Corona Borealis) near his southern shoulder marking what was once the Herdsman's uplifted arm.

Low down between the south and southwest we find the head and shoulders of the Centaur (Centaurus), who holds the Wolf (Lupus) due south. Above the Wolf are the Scales (Libra), and above these the Serpent (Serpens), his head in the south, stretching toward the Crown. In the mid-sky, toward the southeast, we find the Serpent Bearer (Ophiuchus—one star of the Serpent lies east of him). Below the Serpent Bearer we find the Scorpion (Scorpio), now fully risen, and showing truly scorpionic form. Beside the Scorpion is the Archer (Sagittarius), low down in the southeast. To his left we see, low down, two stars marking the head of the Sea Goat (Capricornus), and one belonging to the Water Bearer (Aquarius). Above the Sea Goat flies the Eagle (Aquila), with the bright star Altair; and above, near the point overhead, is the kneeling Hercules. Due east, we see part of the Winged Horse (Pegasus); above that, the little Dolphin (Delphinus), and higher, the Swan (Cygnus) and the Lyre (Lyra), with the beautiful bluish-white star Vega. Lastly, low down, between north and northeast, we find the Seated Lady (Cassiopeia); and above, somewhat east-wardly, the inconspicuous constellation Cepheus, Cassiopeia's royal husband.

matter in an extremely fine state of division. Now it has been shown that the radiations of the sun have the power of re-pelling matter, whilst the sun itself attracts by its gravitational force. But there is a difference in the action of the two forces. The light-pressure varies with the surface of the particle upon which it is exercised; the gravitational attraction varies with the mass or volume. If we consider the behaviour of very small particles, it follows that the attraction due to gravitation (depending on the volume of the particle) will diminish more rapidly than the repulsion due to light-pressure (depending on the surface of the particle), as we decrease continually the size of the particle, since its volume dimin-ishes more rapidly than its surface. A limit therefore will be reached below which the repulsion will become greater than the attraction. Thus for particles less than the 1/25000 part of an inch in diameter the repulsion of the sun is greater than its attraction. Particles in the outer envelope of the comet below this size will be driven away in a continuous stream, and will form that thin, luminous fog which we see as the comet's tail.

We cannot tell whether such objects as these were present to the mind of Joel when he spoke of "blood and fire and pillars of smoke"; possibly these metaphors are better explained by a sand- or thunder-storm, especially when we consider that the Hebrew expression for the "pillars of smoke" indicates a resemblance to a palm-tree, as in the spread-ing out of the head of a sand- or thunder-cloud in the sky. The suggestion has been made,—following the closing lines of Paradise Lost (for Milton is responsible for many of our interpretations of Scripture)

"High in front advanced, The brandished sword of God before them blazed, Fierce as a comet," —that a comet was indeed the "flaming sword which turned every way, to keep the way of the tree of life." There is less improbability in the suggestion made by several writers that, when the pestilence wasted Jerusalem, and David offered up the sacrifice of intercession in the threshing floor of Ornan the Jebusite, the king may have seen, in the scimitar-like tail of a comet such as Donati's, God's "minister,"—"a flame of fire,"—"the angel of the Lord stand between the earth and the heaven, having a drawn sword in his hand stretched out over Jerusalem." The late R. A. Proctor describes the wanderings of a comet thus:—"A comet is seen in the far distant depths of space as a faint and scarcely discernible speck. It draws nearer and nearer with continually increasing velocity, growing continu-ally larger and brighter. Faster and faster it rushes on until it makes its nearest approach to our sun, and then, sweeping round him, it begins its long return voyage into infinite space. As it recedes it grows fainter and fainter, until at length it passes beyond the range of the most powerful telescopes made by man, and is seen no more. It has been seen for the first and last time by the generation of men to whom it has displayed its glories. It has been seen for the first and last time by the race of man itself."

"These are . . . wandering stars, to whom is reserved the blackness of darkness for ever."

Editor’s Note: I hope you liked this article. If not, submit an article of your own.

June 2010 Volume 16 Number 12 Page 7

For Sale

Portable Equatorial Mounting with Driving Clock. This instrument was designed to meet the demand for portable low priced telescope suitable for the study of astronomy in the college, high school or for the amateur astronomer. Every ob-server and teacher in astronomy will appreciate the great usefulness of a driving mechanism, which will keep the star in the field during observation. After several years of experimenting we have succeeded in constructing a reliable clock which can easily be attached to our portable telescope mounting. The instrument is mounted on strong hardwood tripod fitted with iron shoes. It is attached to the tripod top by a single screw which holds it firmly and allows adjustment in azimuth. The clock case carrying the bearing for the polar axis is made to swivel in the base casting, so that the polar axis may be easily set and firmly clamped at an angle from horizon-tal to vertical. A level is fitted to the tripod top and a graduated arc is fastened to the clock case. If the polar axis is set vertical and the worm wheel unclamped, the instrument is transformed into an alt-azimuth mounting. This feature will be found to be a great convenience especially for terrestrial observations. Both the polar and declination axes are carefully fitted to their bearings and carry finding circles. The right ascension cir-cle reads to 5 min., the declination circle to single degrees. The declination axis is fitted with clamp screw which is within convenient reach. The clock has ample power and is enclosed in a heavy case which protects it from dust and injury. It is driven by two strong springs and will run about 12 hours without rewinding. A lever for starting or stopping is provided. Motion from clock to polar axis is transmitted by means of a set of bevel gears and worm and worm wheel. The worm wheel is held by friction to the polar axis so that the telescope can be moved without loosening any screw and without affecting the clock. The clock will give steady and accurate motion to the telescope and with ordinary care it will keep in good repair for years. A slow motion adjustment independent of the clock is fitted to the polar axis. With the instrument are furnished three celestial eye pieces giving a magnifying power of about 50, 100 and 150 diame-ters respectively. The instrument is easily portable, the total weight of a 3" telescope being about 60 lbs. yet it is made heavy enough, and the material well distributed to insure strength and steadiness. Workmanship and finish of the instrument are the best. The brass parts are either lacquered yellow or bronzed. The iron parts are durably enameled and all exposed steel parts are nickel-plated. A120. Telescope of 3" aperture. Price $190.00 A121. Telescope of 3½" aperture, the same as above but the bearing parts made proportionally heavier. Price $240.00 A122. Telescope of 4" aperture. Price $320.00 A140. Finder fitted to 3" telescope. Price $12.00 A150. Positive Eye Pieces. (Ramsden), focus 6 mm. to 25 mm. Price $4.50 A151. Negative Eye Pieces. (Huygenian), focus 5 mm. to 25 mm. Price $4.50 A152. Diagonal Eye Piece. The prism of the eye piece has guaranteed optically plane surfaces and will not affect the definition of the telescope. Price $12.00 A153. Terrestrial Eye Piece, focus 25 mm. Price $12.00 A154. Sun Caps, to fit above eye pieces. Price $1.50

We have constructed clocks for a number of larger telescopes among others the clock for the 24 in. Lowell Refractor

From the 1908 catalog of WM. GAERTNER & CO. 5345-5349 Lake Ave.

CHICAGO.

June 2010 Volume 16 Number 12 Page 8 Moondark is on hiatus this month. The column should return soon. Look here or keep an eye out on the Moondark web site ).

Astrophotos by Members and Friends

How to Join the Delmarva Stargazers: Anyone with an interest in any aspect of astronomy is welcome NAME________________________________________________________________________________________ ADDRESS_____________________________________________________________________________________ CITY, STATE & ZIP______________________________________________________________________________ E-MAIL ADDRESS (If any)_________________________________________________________________________ Do you need the newsletter snail mailed to you (Y/N)?___________________________________________________ Please attach a check for $15 made payable to Delmarva Stargazers and mail to Kathy Sheldon, 20985 Fleatown Rd, Lincoln, DE 19960. Call club President Don Surles at 302-653-9445 for more information.

Dusty emission nebula IC 410 lies about 12,000 light-years away in the constellation Auriga. NGC 1893 is a bright star cluster seen just above the prominent dark cloud near the center of the picture. Two stream-ers seen in the 1 o'clock position are com-monly referred to as "The Tadpoles." This image taken through a Hydrogen alpha filter is a composite of nine 30 minute ex-posures made through my 5" refractor tele-scope with an ST-10 camera. It will be the luminescent part of a LRGB color photo someday. Joe Morris

here are 3 shots of the International Space Sta-tion passing over...that's Venus next to the tree. Don Surles