StarWatch for the greater Lehigh Valley



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1155    OCTOBER 7, 2018:   Thinking about a Telescope this Christmas?
We are 11 weeks away from Christmas, and if you are considering buying a telescope for under the tree, now is the time to start thinking about that purchase. Unfortunately, most people wait to the last moment; and so as a result, they are rushed in their decision, pay too much money, and get frustration in return. If a manufacturer hypes the power that a telescope can attain as the chief reason for purchasing the scope, stay away from that item like it’s poison ivy. I’m sorry to say that scopes sold at K-Mart, Walmart, or for that matter at any large retail outlet are a joke. For a while, QVC was hyping telescopes for about $100 per unit, and they were absolutely atrocious. Here is the bottom line. If you are unwilling to commit a minimum of about $500 to purchase a scope with a steady mounting (support) system, good optics, and at least two quality eyepieces, buy a decent pair of binoculars instead. Most smaller versions are light in weight, ergonomically designed, and they are immediately ready for use. In all cases you will see the image right-side up, over a wide field of view, and be able to use them during the day, as well as at night to look at awe-inspiring starscapes. My suggestion would be to purchase binoculars that produce a magnification of eight power with a 42mm light gathering objective, or an 8x42 pair. Seven by 50s (7x50) are generally considered best for viewing the night sky, but they are bigger, heavier to hold, and only achieve their full potential in dark, rural locales. You’ll probably spend about $150 for a nice pair, and if you don’t drop them or allow them to fall into the swimming pool, you’ll use them for the rest of your life. All telescopes are a compromise in one way or another, but all experts agree that telescopes are not built strictly for magnification. The most important aspect of a telescope is its ability to gather light and to bring that light to a comfortable, sharp focus. The eye, acting as the receptor of the light being gathered by the lens or mirror, is essentially enlarged to the diameter of the light-gathering mirror or lens of the telescope. Telescopes also need to produce crisp, vivid (high contrast) images of what the observer is trying to view. This requires optics that meet the criteria for generating astronomically acceptable images. When a manufacturer chooses quality over an avalanche of profit, superior images can be attained. The observer can easily see details on the moon, planets, and other objects in the sky. Telescopes also need to produce acceptable fields of view, so that the object under scrutiny can be seen in its entirety. Here is where a quality, wide-angle eyepiece can add your enjoyment. A telescope must also be attached to a sturdy mounting system to dampen unwanted vibrations when it is repositioned to find a new sky object or to hold it steady if the wind kicks up a little. When all of these criteria are met, then the topic of magnification can be discussed, but there are still limits. The best telescopes will not tolerate any more than 50 to 60-power per inch of light-gathering aperture. A quality, reflecting telescope with a 4-inch mirror should not be pushed beyond 200-power. Where can you find a quality telescope at a fair price? I would first suggest contacting Skies Unlimited serving the Greater Philadelphia, south Jersey, and Lehigh Valley areas ( in Pottstown, PA, at 46 Glocker Way, 19465 (888-947-2673). They normally have used and new equipment on their showroom floor, real telescopes, and many at affordable prices. Skies Unlimited has been influential in helping Moravian College upgrade and repair many of the donated telescopes that it has acquired during the past four years. Talk to Bob, Ted, or Dave for a no pressure introduction to the telescope market and feel free to mention my name. They will listen to your needs without trying to coax you into a decision. I really think that is what makes Skies Unlimited extra special. Also, not to be forgotten is Orion Telescopes in California which produces economical instruments that meet astronomical criteria ( Examine their GoTo Dobsonians which are reasonably priced and will provide you with years of enjoyable views of the nighttime sky.

1156    OCTOBER 14, 2018:   Binoculars Under the Tree?
The more I thought about last week’s article which touted giving a telescope for Christmas, the more I wanted to hype a less spectacular gift, but one that has a greater practical value for the nature/astronomy enthusiast. How about binoculars under the tree? Unless you are a purist and consumed with having the best optical system, you don’t have to spend thousands of dollars to own a pair. My price point would be between $100-$200 for a rugged unit that would satisfy both terrestrial and celestial pursuits. Most smaller binoculars are light in weight, ergonomically designed, waterproof or water resistant, adjustable for the peculiarities of each eye, and they are immediately ready for use right from the box. In all cases you will see the image right-side up, over a wide field of view, which will make it much easier to find your target. What potential buyers normally don’t realize is that binoculars are an extremely personal item, not because of the way they look, but because of each individual’s visual uniqueness. I would inform the intended recipient to come along so that she or he could make the choice to obtain the best fit possible. Stores like Dan’s Camera City, outdoor retailers like Cabela’s, Hawk Mountain Sanctuary, Skies Unlimited, and even Walmart will provide you with ample opportunities to try before you buy. When you start shopping, you’ll see a number on the binoculars, like 8x42, 7x35, 7x50 or 10x80. The first number tells you the magnification which the binoculars will produce, while the second number tells you the diameter of the objective, the initial lens that will be gathering the light that will eventually bring the image into focus by the eyepiece. The magnification also infers something else. Every time you jiggle those binoculars as you try to hold them steady to view that deer or star cluster, vibrations will be amplified by the amount of the magnification. Trying to hold a pair of 15x80s steady is a formable challenge which will undoubtedly result in the extra expense of purchasing a tripod and binocular holder. I think eight power can act as a good limit for your first pair. The light-gathering objective tells you something else. The larger the objective, the bigger the internal components, and the bigger and heavier the binoculars will become; so not only will a 15x80 or a 10x80 pair markedly increase the annoyance of any hand-held vibrations, but they will become unbearably heavy after holding them for just a few minutes. Here are some other thoughts which I consider extremely important. Take the magnification and divide it into the diameter of the lens, and you will have the size of the eyepieces’ exit pupils in millimeters. This is the diameter of the light cone which is produced at the position of best focus. Your eyes must be properly centered on it to see the image. If you are a 20-year old and don’t smoke, the iris of your eye should be able to open to about 7mm if properly dark-adapted in a rural locale, but if you are middle-aged, that number drops down to perhaps 5mm or 6mm, so there is no need to consider a 7x50 pair of binoculars that will give you a 7.1mm exit pupil. Your eye simply will not be able to gather all of the light which the binocular is bringing to focus. Eight by 42s or 7x35s would be a wiser purchase. In addition, most of us live in urban or suburban regions where light pollution won’t allow the eye to become fully dark-adapted, and therefore, reach its maximum opening, again negating the need to purchase binoculars which produce the optimal exit pupil for astronomical viewing. Finally, there is something called eye relief that must be considered. The eye relief represents the distance from the outermost lens of the eyepiece to the position of best focus. Viewing in front of or in back of this position will give you a restricted field of view. If you wear glasses and want to have them on while observing, I strongly recommend that you should buy binoculars with an eye relief of 18mm-20mm. That one factor will increase the cost of your purchase, but the binoculars that are bought will have better optics and the comfort of your view will make the higher price worthwhile. Magnification, size, weight, exit pupil, and eye relief are a lot to consider. Purchase wisely, and you’ll have a lifelong friend to make the world and universe a more enjoyable place to observe.

1157    OCTOBER 21, 2018:   No Playbook for a Robotic Observatory
I remember after 9-11 all of the extensive planning that went into protecting Dieruff High School in the event of a terrorist attack. When the moment came for the big test—teachers were unaware of its timing—I was headed back to Dieruff from William Allen High School where I taught astronomy during first period. I parked, grabbed my well-worn box of teaching materials, walked into the building and up the steps towards the planetarium. “Bang, bang,” I heard someone say. “You’re dead!” I had entered the hot zone and was killed. Later that day, I was verbally admonished by administration for ruining the drill. My response was simple. “Didn’t anyone ever think of locking the outside doors when the test began? Then I would not have been fatally wounded.” Administration looked perplexed as they often did. No one in all of those meetings had thought of that simple scenario. Building the Mars Desert Research Station Robotic Observatory to which Moravian College has a 25 percent time-share has had a similar ring to it with the exception that we have never made mistakes as blatant as leaving the doors (dome) open. But no matter how well you plan, the unforeseen always happens. It has been an interesting learning curve. We were promised by the Mars Society stable power and a stable Internet. They fulfilled their pledge with high-speed Internet and a wonderful solar power system that electrified the entire MDRS facility including our observatory, but the batteries gave out because they overheated during this past exceptionally hot summer. The roasting of the batteries was exacerbated by the fact that there was no draw on the system because MDRS was shut down during that period. All of the batteries will be replaced, the domed biolab in which they are housed will be air conditioned, and certain other areas of the habitat will remain electrified year-round to create a continuous draw on the system during the months when the habitat is not in use. In addition, a backup generator, which automatically started if the solar system indicated low power reserves, also failed when the solar grid collapsed. This completely drained the observatory’s backup battery system at night and dropped all connections with the Internet. Then occasionally during the day the solar system would restore itself, and the observatory batteries would recharge to be completely drained once again during the following evening. The observatory went dark. At that time, Peter Detterline was teaching a new Moravian online course on astronomical research in which students after the mid-term were going to make extensive use of the robotic observatory. Pete flew to Grand Junction, Colorado at his own expense on October 14 to facilitate the repair of the observatory in Utah and bring it, the Celestron Edge telescope, and the 10 Micron mount from Deep Space Products back online. He found the main Boltwood automated weather sensor had malfunctioned because water had leaked along a wire into the control box which interfaced the weather station with the operation of the dome, telescope and mount. MDRS had received extensive tropical precipitation about a week before and from several summer storms. A new control box was ordered. Meanwhile, our backup Davis weather station which was integrated into the Boltwood unit began to operate the observatory robotically and data for the first time began to flow to Moravian students who were ecstatic at its reception. The replacement control box from Boltwood also arrived, and everything seemed on track for a final repair. Then MDRS experienced another unusual heavy rain event. The backup MDRS generator failed, causing the observatory’s backup batteries to fail permanently. In addition, the telescope became wet on the inside. However, conditions again are on the mend. As I was just writing those dire words, Pete sent me a picture of the site—dome open, with a beautiful blue sky accented by a few puffy clouds. We will solve these problems through the input from many knowledgeable individuals who have struggled with similar problems in the past and who have been pulling for the success of this project. October 20 saw the robotic observatory back online again. Kudos to Peter K. Detterline for his dedicated efforts to make this project and his course on astronomical research a success.

[Moravian-MDRS October Refit]
October Moravian-MDRS Refit:From near catastrophe to celebration these images show the highs and lows of the latest refit conducted by Peter Detterline during the October 2018 work which brought the MDRS Robotic Observatory back online. The celebratory image is the center one, where the automated aspects of the observatory have assumed control and the dome has opened on it own with the Celestron telescope and 10 Micron mounting system from Deep Space Products ready to “rock and roll.” Images by Peter K. Detterline and BloomSky...

1158    OCTOBER 28, 2018:   

[October Star Map]

[October Moon Phase Calendar]