Wednesday, November 5, 7 p.m.: Regular monthly meeting, Carlisle Visitors Center. * * ** **

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1 Lorain County, Ohio November 2014 Website: blackriverastro.org Newsletter submissions: Editor * * * * Wednesday, November 5, 7 p.m.: Regular monthly meeting, Carlisle Visitors Center. * * ** ** * * * * * Thursday, November 13, 7 p.m.: Board Meeting, Blue Sky Restaurant, Amherst, Ohio * * * * ** * * * * Friday, November 21, 8-10 p.m.: Public observing, Nielsen Observatory * * * ** * * Saturday, November 22, 8-10 p.m.: Cloud backup public observing, Nielsen Observatory * * * * * ** ** * * * * * * * * *

2 Board Summary, October 9, 2014 The meeting was called to order at 7:08 p.m. with nine Directors present. The minutes were read and approved, as was the Treasurers report. Committee reports followed. Bill Ruth, our Guidescope editor reported that all is well with the newsletter. Under Website, Lee Lumpkin reported that the website and the Forum are operating well and are being used. The Instrumentation report was next, with John Reising informing the Board that he has purchased new 125mm Losmandy rings to better hold the finder scope on the black C-14 as the old rings were too small to hold it properly. We will sell the 100mm rings on Astromart if no one in the club wants to buy them. The Orange C-14 has an issue with the declination lock slipping due to wear. Greg Cox will remove the cam and fabricate a new one as soon as he can get out to the observatory. The blue refractor that we used to use with our Coronado solar filter has some issue in the air-spaced lens at the front of the tube. John Reising will dismantle it and see if there is condensation there or perhaps mold. If it can be effectively cleaned, we may try to sell the scope. The Metro Parks liaison report was postponed until New Business. Programing is set until April. October will be Kelly Ricks who will report on her summer spent as a Dark Ranger, running astronomy outreach at Brice Canyon National Park. November is on hold pending the availability of a speaker. December is our annual Christmas party at the Beaver Creek Reservation in Amherst. January will be a DVD on an astronomy topic of interest supplied by Greg Zmina. In February, Dave Lengyel will do a program on how to use the Sky and Telescope Annual Sky Calendar, with copies of the calendar being provided to all who attend. In March, John Reising will speak on doing a Messier Marathon. There were only a few items of Old Business. First was getting the loaner dobsonian from Kelly Ricks to Roy Klein. Kelly will bring the dob to the next Public Observing session or, if those get cancelled, to the next General Meeting to transfer to Roy. Secondly, Greg Cox is going to order a new batch of hats for the club to sell. These will be baseball caps that are white with Black River Astronomical Society written in blue script on the front. He will order approximately 30 hats, once he determines the price and delivery time. We hope to have these for the November General Meeting for a cost of about $15.00 each. The third item of Old Business concerns dates for outreach programs at Wellington Reservation. Kelly Ricks will be contacting them to set these. The first item of New Business was the happy task of voting in new members. The club wishes to welcome Cody and Brendan Keenan of Columbia Station and Michael Fury of Amherst to our ranks. We are delighted that you have joined us. It was noted that we have had six new members join in the last two months. The second New Business item was a brief discussion about purchasing a digital projector for club use, mostly by our Outreach Committee members. President Schauer passed out handouts on four different projectors at different price points, and a discussion was held about what features we need. The Outreach people will consider what features we need most and the topic will be discussed again at the next meeting. We will also explore what kinds of materials we will be getting from the Night Sky Network as a result of our participation, to see if those impact our choice of projector. The next topic of discussion took the most time. We may switch our participation away from International Sun Day in favor of a festival approach to the solstice. We are considering an event where we would still observe the Sun, but we would include live music and art. The planned date is June 21, 2015 at one of the Metro Parks facilities. There have been some political issues with participating in

3 Sun Day which is why we are considering the switch. More information will be forthcoming as we explore facility availability, and do further planning. The last topic was the selection of a date for next year's OTAA Convention. We looked at a New Moon period as early in September as possible and decided on September 12 th. John Reising will contact the Birmingham Methodist Church to see if the hall is available for that date. A date as early in September as possible is desirable, because they usually have the parking lot fenced off later in the month in preparation for a large craft show held there. Event dates were set, and the meeting was adjourned. ~Steve Schauer *** The Blood Moon Prophecy: Myth vs. Fact Right now, we are in the midst of a 'tetrad' of 'blood moons.' In astronomical terms, we are in the middle of a series of four consecutive total lunar eclipses. For many in the astronomical community, this presents a great opportunity to catch one of the greatest sky shows out there. For prophets of doom, though, this a harbinger of the End Times. Starting in 2008, pastor Mark Biltz began teaching that the Second Coming was near. How does he know that? According to Biltz, he has discovered astronomical patterns (which he has yet to reveal) that led him to believe that the next tetrad of eclipses would coincide with the end times. Using technology such as his website and YouTube to spread his message, Biltz quickly built a cult-like following with modern-day doomsday believers. Cue our next prophet of doom. Writing in his 2013 book Four Blood Moons: Something is About to Change, John Hagee notes that the last three tetrads corresponding to the Jewish feasts of Passover and Sukkot (as this current one does) correspond to pivotal events in the history of the Jewish people: the expulsion of the Jews from Spain (1492-3), the founding of modern Israel ( ), and the Six Day War ( ). As a result, thanks to the rarity of tetrads and their past correspondences with important events in the history of the Jews, Hagee predicts that something big is just over the course of the horizon that could mark a dramatic shift in the fortunes of the Jewish people, and, thanks to the global society we now live in, the world as a whole. Now for facts. Myth: Tetrads are rare Fact: There have been 62 of them in the past 2,000 years. Myth: All previous Tetrads falling on Passover/Sukkot coincided with major events in the history of the Jews Fact: Tetrads that took place in the following years 162-3, 795-6, 842-3, and corresponded to no major events in Jewish history. In fact, the tetrad is a bit of a stretch as modern Israel was founded in Myth: Isn't it odd that lunar eclipses fall on Jewish holidays? Fact: No, the Jewish calendar is based on the lunar month Myth: the Moon can impact events here on Earth Fact: Tides aside, no it can't

4 For fundamentalist Christians, the Bible is literal truth, case closed. However, there's no denying that the holy book can be very vague at times. Let's take a look at the verses Joel 2:30-31, which state that (30) And I will show wonders in the heavens and on the earth, blood and fire and columns of smoke. (31) The sun shall be turned to darkness, and the moon to blood, before the great and awesome day of the Lord comes. This is the passage that Biltz uses as the basis for his Doomsday prediction. Myth: lunar eclipses and solar eclipses only rarely follow each other Fact: Thanks to celestial geometry, a lunar eclipse will always be followed by a solar eclipse 2 weeks later (that's roughly 4,000 such cycles in the last 2,000 years, nothing rare here) In the end, what do we have? Well, how about two prophets of doom with theories filled with more holes than a block of Swiss cheese. Case closed. ~Denny Bodzash Total lunar eclipse, October 8, 2014 Images by Denny Bodzash

5 Mapping What You Cannot See, Cannot Know, Cannot Visit by Robert Krulwich Link to article: When I was a boy I had a globe. I could take it in my hands, rest it on my lap, give it a spin and look down on Africa, Europe, North America and Asia spinning by. In 1961 (I was 13), cosmonaut Yuri Gagarin left the planet and got high enough to look down on the real Earth spinning beneath him. He was the first (followed by Alan Shepard and later John Glenn), to gaze with his own eyes on what we had over the centuries so carefully mapped, drawn and imagined. From 160 miles up, you can take in the whole boot of Italy, the Red Sea narrowing to Suez, North America tapering down to the isthmus at Panama, and the amazing thing amazing to me, anyway is that what we'd spent 2,000 years drawing in our heads was actually there. We'd gotten it pretty much right! Of course, you say. Cartography is a science. What it describes should be there. And yet, I find myself a little surprised by our ability to measure, to extrapolate, to conjoin, to build a true whole from a gazillion little parts. It's an enormous intellectual feat. And now, I'm happy to report, it's been done again on a scale that boggles my mind. Nature Video/YouTube R. Brent Tully, an astronomer at the University of Hawaii at Manoa, and his team have mapped a hunk of the universe that is 500 million light-years across. It contains 100 million billion suns including our own little star. Their new map, like our early Earth maps, is built from detailed observations, intense data crunching and, when assembled, it pictures a galactic neighborhood he calls "Laniakea" that's a Hawaiian name that the video below translates as (oddly) "immeasurable heaven."

6 But they measured it. What you will see in this video is the first coherent map, not of our Milky Way, but of the Milky Way's larger neighborhood, a branching "supercluster" of galaxies, being pulled, pushed and splayed over what I thought would be an unimaginable, unmappable distance but here it is. As the video will show you, we are at the far, far edge of a long branch of swirling stars, an impossibly small seed dangling from an immense tree of light. Obje A Postscript: We Have Done This Before Looking at this, I'm reminded that we have been imagining spaces we cannot see for thousands of years. Back in 240 B.C., in ancient Alexandria, an astronomer named Eratosthenes got a letter from southern Egypt. The letter writer commented that where he lived there's a day the longest day of the year (what we would call the summer solstice) when a person casts no shadow. None at all. At exactly noon where I live, the southerner wrote, the sun is directly over my head, not a single degree north, south, east or west. For that moment, I am shadowless. Me And My Shadow Hmm, thought Eratosthenes, that doesn't happen where I live. Here in Alexandria on the longest day of the year at noon, the sun still casts a slight shadow. That got him thinking: What if the earth is curved? Maybe sunshine is falling straight to Earth, but the shadow I see in Alexandria is telling me that I'm at a different angle to the sun than my friend down south? Maybe these shadow differences are telling us we are living on a giant sphere. He measured the distance between Alexandria and Syene, Egypt, where his friend lived. Then, on the next solstice, he put a stick in the Alexandrian ground, measured the shadow at noon, and was able to calculate (using trigonometry, based on the different lengths of shadow) how big the Earth might be. What's amazing is he got very close. He imagined an Earth bigger than the one we live on, but since we don't know how Eratosthenes measured distances exactly, his calculations were either 16 percent too

7 big or just 2 percent too big. Either way, he was conjuring up an immense ball, hundreds of millions of times bigger than he was, and when Yuri Gagarin got to see what Eratosthenes had imagined, it turns out, Eratosthenes was pretty much right. Go figure. (Come to think of it, that's what Eratosthenes did. Using a stick, a shadow and his head, he figured out what he was standing on. On our good days, we humans are very, very good.) *** Partial solar eclipse, October 23, 2014 Image by Denny Bodzash Here's a link to a noteworthy solar article be sure to watch the video, in full screen. There's a soundtrack, too: *** ***

8 (Thanks to Jeff Walsh for forwarding the following article)

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10 Facts About Telescope Magnification The telescope is often thought to magnify celestial objects too far away to view unaided. While this is true to a point, the fact is that the telescope's primary purpose is to collect light. The reason we can't see many celestial objects isn't because they're too distant or tiny, it's because they're too dim. If we could see the Andromeda Galaxy or Orion Nebula in full illumination, it would appear larger than the full moon. The larger the primary objective (aperture or iris), the more light can be captured, the brighter the view. Advanced technology offers yet even more enhancement to this fundamental premise... electronic light detectors, that is, digital cameras, more sensitive to light and able to accumulate the light received. So having said that, we turn to the issue of magnification. Some definitions first... "Magnification" is mathematically defined a number of ways, some by complex formula, others quite simple. For the sake of expediency, we'll use "simple". The term most often used to identify magnification is "Power", symbolized by the letter "X" otherwise termed "Times". "1X" is what the human eye normally sees. "2X" is twice, or 2 times normal image size. The objective is to make an image appear larger. Excluding space based telescopes and mountain top super-scopes, most professional and amateur astronomers agree on the following table as "Best Range of Telescope Magnification"... For Lunar, Solar & Sky Deep Space Objects Solar System Planets Power 50x or less 50x ~ 150x 150x or more Magnification should be increased only to enhance detail. The more magnification used, the less light reaches the eye (or camera) and the more distortion is enlarged as well. Large scopes can magnify more because the pool of light is large enough to sacrifice for the sake of "bigger" over "brighter". However, a "bigger" image isn't necessarily better. Every telescope has a limit to how much magnification it can accommodate. Beyond that limit, the image becomes so dim and blurred as to become irresolvable. Though the following formula isn't exacting, it is useful and true. If the scope is measured in millimeters... Max Mag = Aperture X 2 (Ex; A 150mm mirror or lens supports a maximum of 300x power.) If the scope is measured in inches... Max Mag = Aperture X 50 (Ex; A 4" primary mirror or lens supports a maximum of 200x power.) Binoculars are rated somewhat differently as their lenses are not changeable. Ratings are given by a set of 2 numbers identifying both power and millimeter size of the primary objective. It gives the buyer/user some idea of what to expect in terms of both big and bright.

11 Getting back to telescopes, they're rated by focal length or f-number (not to be confused with f-stop). The focal length indicates how far light must travel from the primary objective to the eyepiece that is, how much light is presented at the eyepiece. The f-number is determined by dividing the telescope's focal length by the telescope's primary aperture or objective size. The smaller the telescope's f -number, the more light is reported by the rating. Lower numbers facilitate dim objects such as deep space targets like nebulae. Higher rating numbers serve better resolution for observing planets and double stars. The magnification power rating is defined by dividing the telescope's focal length (in millimeters) by the eyepiece focal length. We can see that by changing the eyepiece, we change magnification. The lower the eyepiece focal length, the higher the magnification. In doing this, remember the maximum power rating of the telescope. The telescope's magnification is increased this way, but as the telescope's limits are approached, the image becomes less clear. Using today's CCD camera technology, even a simple webcam can be modified to enhance a telescope's light capturing ability. A camera mated directly to the telescope, will act as a 10mm to 15mm eyepiece. Using a camera may require employing additional optics to reduce the telescope's focal length. This may be necessary to keep the imaging train within the telescope's magnification limits. Lastly, a word about using Barlow Lenses. Their function is to act as a focal length multiplier. A 2X Barlow multiplies the focal length by 2, resulting in doubling magnification. This arrangement, however, will square the amount of light reduction. A 2X Barlow reduces light to 1/4th... a 3X to 1/9th, a 5X to 1/25th, etc. This is a huge reduction in light. If the scope can't collect a sufficient amount, the image will be extremely dark, greatly increasing time exposure or becoming too faint to be seen by the naked eye. In summary... Establish the telescope's magnification limits. Select an appropriate eyepiece best suited for the intended observation. Exceeding the telescope's power limits severely degrades image quality. The CCD digital camera is the newest of tools to enhance the telescope's light processing performance. Increase magnification only to improve detail. An image train is only as good as its weakest component. Magnification reduces light and amplifies both distortion as well as detail. There's no substitute for quality. However, more $$$ isn't always necessary if you understand the function enough to make the adjustments. ~Len Jezior

12 The OTAA is an association of amateur astronomy clubs in Northern Ohio, primarily stretching the length of the Ohio Turnpike, who have banded together to provide enjoyable, family-oriented activities that focus on astronomy and space sciences. Throughout the summer months each member group hosts a conference and invites all the other member organizations to their site for Solar outreach, Star Parties, talks and presentations and some of the very best food you'll find anywhere in the world!!! The Ohio Turnpike Astromomers Association Partners include: Astronomy Club of Akron: Black River Astronomical Society : Chagrin Valley Astronomical Society: Cleveland Astronomical Society: Cuyahoga Astronomical Association: Mahoning Valley Astronomical Society: Richland Astronomical Society: The Wilderness Center Astronomy Club: ~John O'Neal