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Lorain County, Ohio February 2015 Website: blackriverastro.org * Newsletter submissions: Editor * * * Wednesday, February 4, 7 p.m.: Regular monthly meeting, Carlisle Visitors Center. Program: Using the Sky&Telescope Sky Guide (guides provided) * ** ** * * * * * Thursday, February 12, 7 p.m.: Board Meeting, Blue Sky Restaurant, Amherst, Ohio * * * * * * * * * * Sunday, February 15, 6:30-8:30 p.m.: Nighttime Stargazing Walk, Wellington Reservation * * ** * ** * * * * * * * ** * * Friday, February 20, 7-9 p.m.: Public observing, Nielsen Observatory * * * ** * * Saturday, February 21, 7-9 p.m.: Backup date, public observing * * * * * ** ** * * * * * * * * * * BOARD SUMMARY, January 15, 2015 The meeting was called to order with eight Directors present. The minutes of the December meeting and Dan Walker's Treasurer's report were both read and approved and it was time for committee reports. Bill Ruth, the Guidescope editor, reported that all is well with our newsletter. Lee Lumpkin reported that the website, forum and gallery are all working well, although he fixed a broken link recently, and John Reising as head of the Instrumentation committee reported that everything in the observatory was in fine shape. The OTAA committee reported that we have been able to secure the Birmingham Methodist Church Hall for our OTAA convention on Sept. 12, 2015. This has been our OTAA “home” for many years. This year the church moved us to “Public Service Organization” status and offered us the hall for free. They did, however state that donations were gladly accepted, so we donated $100. The MetroParks Liaison had no report. Programming is set through August with BRAS members interested in giving a program asked to contact any Board member. Our programs will be: February--Dave Lengyel--Using the Skygazers Almanac (a copy will be given to all who attend). March--John Reising--Messier Marathon April --Steve Schauer--The BRAS Year in Review and coming events May--Kelly Ricks --TBA June--Dave Lengyel--Old School slide presentation July--Dan Walker--Equation of Time August--Len Jezior--Optical Filters: Why, How and When? Under Old Business, Schauer reported on the progress of the Worldwide Solstice Festival Committee and stated that the Board needed to form a Publicity Committee soon. He asked that Board Members think about methods of getting publicity for the Festival and that we form such a committee at the next meeting. The most time was spent on setting the dates for Public Observing for 2015. The dates and times have been set and have been sent to Tim Fairweather so that they can be put in the Lorain County MetroParks newsletter, the Arrowhead. Lee Lumpkin will also enter them into the BRAS calendar. There was also a brief discussion about Charlemont permits for members who want them. Charlemont is a MetroParks reservation in southern Lorain County, south and a little west of Findley State Park. It is unimproved, consisting of a gravel parking lot and hiking trails. It is closed at night unless one has a permit to use the property. The draw here is that the skies are very dark with few lights in the area. The LCMP Liaison, Steve Schauer, will contact the Parks to see if we can get six permits. This way any members who want to travel to Charlemont to observe or photograph only need one of the permit holders to accompany them. We will try to get permits in the hands of members who are retired and who live in central or south Lorain County as they would be the people most likely to be available. There was only one item of New Business. This was a discussion of Comet Lovejoy and trying to hold an observing session for the public. We had Public Observing planned on the 16th and 17th, but we decided that if those dates were clouded out, we would try to contact the LCMP about an impromptu Public Observing session the next weekend (the 23rd,24th). Those dates would not be in the Arrowhead, but they could be put on the MetroParks website and Facebook page and we would do the same. UPDATE: Friday the 16th was cloudy, but we were able to observe on the 17th and got a good look at the comet. Lee Lumpkin and John O'Neal photographed Lovejoy and others used binoculars and telescopes to observe. In the C-14 with a 55mm Plossl, a tail was visible. Dates were read for January and February and the meeting was adjourned. --Steve Schauer * WANTED: Clock-driven equatorial mount for 10" tube. Can be slightly larger or smaller than for 10". Contact Len Jezior [email protected] (440) 453-8444. * A LOOK AT EYEPIECE FILTERS Many fellow amateur astronomers rarely use eyepiece filters during their observations. I'm not sure why, but they're missing out on "better" viewing. In fact, simple color filters and more complex band filters can greatly enhance images. It must be said at the onset that by their very nature, all filters reduce light. This characteristic suggests filters are not recommended for use on small telescopes, those rated with very high f -numbers or when using high magnification. Filters fall within two categories, band specific & neutral density. Starting with "band specific" filters, these are designed to influence light within a specific range or frequency. Among the more complex, first and foremost is the broadband filter. A nebular filter strongly rejects the light of sodium and mercury-vapor lights as well as natural airglow and auroral emissions. Conversely, the strong nebular emission in the visual regions of 486nm (Hydrogen Beta, or Hß) and 496 to 501nm (Oxygen-III, or OIII), are passed through the filter with high percentages. The effect is that nebular light reaching the eye is dramatically increased in detail, while the effects of city light pollution are greatly reduced. Unless you're observing from some distant mountaintop or desert, light pollution is a problem nearly everywhere. The narrowband filter's primary application is in reducing light pollution with remarkable results. This filter passes the two spectral lines of Oxygen III at 496 and 501nm and the Hydrogen Beta line at 486nm while rejecting all others. Nearly 100% of city light emissions are rejected in this way while favoring nebular artifacts. Both narrow and broad band filters result in significant overall light reduction. Best results occur in using these with lower magnification (no Barlows) and/or with scopes rated with a 15 f-number or less. While neither filter is meant for photographic application, they can still be applied to digital cameras with satisfactory results. The highly reflective surfaces of these filters can induce aberrations when applied with other filters and when performing long time exposure photography. Another type of band influencing filter are color filters. One might think that filtering a color range would yield little improvement, but it can. These filters are quite inexpensive and easy to apply with a basic understanding of the artist's color wheel. Briefly reviewing this feature, there are 3 primary colors, red, yellow & blue. Between these 3 are 3 secondary colors created by blending 2 adjacent primary colors... orange (red + yellow), green (yellow + blue) and purple (blue + red). / RED PURPLE | ORANGE X BLUE \ \ | YELLOW GREEN / These 6 colors are arranged in a circular or clock-like format starting with red at the 12 o'clock position and green at 6. In this hexagonal framework, the colors facing opposite sides of the wheel are termed "complementary" colors. Complementary colors blended together make a dark gray (black). Using color filters exploits this characteristic. For example, Jupiter's predominant color is orange, Mars, a rusty red. By using a filter of complementary color, blue (or green), the red-orange hue appears darker, more grayish in appearance. This will produce a higher contrast or distinction between the remaining white, brown, yellow and blue hues. The overall image will take on the color of the filter but if you're creating digital photos, this coloration can be adjusted later, leaving natural colors of higher definition. The key to successful application is in using a filter of complementary color to the general overall color of the object. That's the short and long of it... no real trick and it works well with both camera and naked eye observation. Polarized & Neutral Density filters... There are two types of polarized filters serving two different purposes. First, the simpler of the two uses a single layer of polarized material. Application is meant for observing the Moon or deep space gaseous artifacts. By rotating the filter at the eyepiece or camera, the object's reflective properties can be manipulated to produce artificial color and increased contrast. The second polarized filter type is comprised of two layers of polarized material. The 2nd layer is mounted immediately above the 1st and is meant to be rotated. The filter is designed to act as a light "spigot", able to meter incoming light. As fields cross, the filter darkens. This is handy to reduce the amount of light presented at the eyepiece for lunar and terrestrial observation. (WARNING: Never use these for solar observation.) Other light reduction filters include the neutral density white light or "smoked" solar filter. These are typically made of either Mylar film or glass. While both are considered equally effective, my personal preference leans towards glass. While more expensive than Mylar film, I find them easier to clean, less likely to puncture, less vulnerable to other damage and less likely to cause distortion. This filter is installed at the telescope's primary objective, not at the eyepiece. Like a welder's mask, this filter is designed to reduce the intensity of visible light as well as reduce harmful infrared and ultraviolet emission. It also protects the image train from the intense heat produced by magnification of the Sun's rays. A split second exposure to unfiltered solar radiation will permanently injure the eye and can instantly damage the camera and telescope components. Solar filters should be installed or removed while the telescope is oriented in a direction looking away from the Sun. Guide scopes are often overlooked. Be sure they're capped or filtered as well. Even if an uncapped guide scope isn't being used, misdirected sun rays can melt or burn components and optical coatings. Solar observation frequently employs the use of special devices or single purpose telescopes. These are designed for singular application to dramatic and even spectacular effect. This, however, is a topic unto itself. With the exception of the front-mounted solar filters, eyepiece filters screw onto the inward side of an eyepiece. However, if you're using an erecting prism, you can attach the filter there. This precludes the need to remount a filter each time you change eyepieces. Also, if you're looking downwards into the eyepiece during observation, another "trick" is to simply drop the filter into the eyepiece's relief cup. This is a fast and easy way to change filters, testing to see which color filter produces the best effect. Since the filter glass has no light-bending qualities, (or at least it shouldn't have), it doesn't matter where within the image train it's located. This makes for as simple use as can be expected. Eyepiece filters are easily found at any telescope accessory website. Buying a "set" of color filters is usually preferred and certainly saves $$$. Prices vary widely so shopping around is recommended but remember, quality counts. Lastly, color filters are not recommended if you're using a monochromatic camera with RGB filters. As you can imagine, a mix of color applications will produce severely negative effects. Color manipulation is much more effective at the post processing stages where color layers can be enhanced or reduced. In summary... o All filters significantly reduce light at the eyepiece. o o Band pass/reject filters help reduce light pollution & enhance contrast. Color filters are best applied using the color complementary to the object's overall color. o o Polarized filter are used primarily to meter light, increase contrast or create false color. NEVER do solar observation without the proper use of solar specific filters or scopes. o o Solar filters are best applied at the scope's primary objective--including guide scopes. Solar observation is inherently dangerous to eyes & equipment. Supervise children. o Color filters are counterproductive with monochromatic imagers using RGB filters. ~Len Jezior Comet Lovejoy, January 13, 2015 photo by Dave Lengyel The History of Naming Heavenly Bodies February brings Valentines Day. While this holiday bring love to the air, it also bring scams of astronomical proportions. Every now and then, especially on late night radio or TV this time of year, one will come across an ad where a business promises to, for a fee, rename a star after your special someone. Cash paid, one will then be mailed an official certificate stating that, indeed, some celestial body is now named after your significant other. Sounds cool doesn't it? Unfortunately, it's all a scam. When it comes to naming heavenly bodies, the International Astronomical Union (IAU) is the only body who's opinion matters. In the past, naming things in space was a kind of Wild West, if you will. At one time, any body or feature on a body was named by whoever discovered it. Usually, the names were respectable and the astronomical community went along with them. However, a turning point came in 1781 when British astronomer William Herschel discovered a planet beyond Saturn. Being a patriotic Englishman, for Herschel, it was only natural to name the new planet after then-king George III, who was so flattered that he became Herschel's patron after the discovery. Herschel's proposed name for the planet: Georgium Sidus (the Georgian Star). However, for people of other nationalities, especially the French, the name wasn't too popular. Not surprisingly, astronomers of other nations didn't adopt Herschel's suggestion for the king-honoring name, opting to call the planet 'Herschel' instead. In time, though, in keeping with tradition, the 7th planet was named Uranus, the Latinized version of the Greek sky god's name, Ouranos. Why Uranus? Simple. Saturn (6th planet) was the father of Jupiter (5th planet). So, in keeping with this father-son trend, it was only natural that the 7th planet should be named for the father of the 6th, which, by default, would be Ouranos (Uranus), who was the father of Saturn. By 1850, Uranus was finally the accepted as the name for the 7th planet (8th planet Neptune being discovered two years previously). So, after the decades-long Planet George/Herschel mess, the rules for naming things in space became more clearly defined as the international community decided as a whole that the names for bodies in the cosmos should not reflect national chauvinism on Earth. In time, these unwritten rules would evolve into the formal procedures of today where only the IAU, not late-night advertisers, can approve the name for any cosmic body. In conclusion, next time you hear an ad where, for a fee, you can name a star, asteroid, or whatever after your special someone, don't only ignore the ad, but then warn your friends of such scams. ~Denny Bodzash Comet Lovejoy and M13, January 19, 2015 photo by John O'Neal Binary Beauties Below is a star chart and a short table with the names, locations and specifications For some of the brightest and easiest binary stars visible in the mid to late winter evening sky. The table includes the following: ADS number: From the ADS double star catalog. Name: Greek letters, (mostly), or numbers with constellation. Celestial Longitude: (RA) & Celestial Latitude: (DEC): for those with equatorial mounts with setting circles. Star Magnitudes: Primary star first & companion star next. Position Angle, (PA): Position of companion relative to the primary star: 0 deg = North; 90 deg = East, 180 deg = South; 270 deg = West. Separation, (“ = arc seconds): Distance between the primary and the companion star. Included on the list are the following, which I consider as some of the absolute finest binary stars in the heavens, (alpha), a Gemini: Castor!! A white / white pair stars with magnitudes of 1.9 & 2.9 at a distance of nearly 4 arc seconds. Wonderful in even the smallest of telescopes but may present a glare problem in some small scopes! (delta), d Gemini: A bright white primary and dim yellow-orange companion well below Pollux about ½ the down the left string of stars in Gemini. Some magnitude difference, (3.5 & 8.0), but separable, ( 6.3 arc seconds), in medium sized telescopes. (beta), B Monoceros: A stunning triple star of 3 blue-blue 5th magnitude stars just above Sirius and to the left and below Orion’s belt. Magnitudes, separations and position angles listed below: 4.5 & 5.4 7.3” 132 deg 5.6 2.8” 106 deg (epsilon), e Monoceros: A nifty pair of white stars just left and slightly below Betelgeuse, (alpha Orion) and just to the right of the “Rosette nebula”. Magnitudes of 4.4 and 6.7 with a separation of 13.3 arc seconds puts this pair within the reach of even small instruments. (zeta), z Cancer: A challenging triple star system of 3, 6th magnitude stars with a white primary and 2 yellow companions, one of which is a mere 1.0 arc second from the primary. Very, very difficult to split the 1 arc second pair. Magnitudes, separations and position angles listed below: 5.6 & 6.0 1.0” 59 deg 6.2 6.0” 72 deg (iota), i Cancer: A very nice “Albireo” class double straight above the M44, (“Beehive”), cluster. A yellow-orange and blue pair at 4th & 7th magnitudes with a separation of 30.5 arc seconds. ~John Reising