THE OBSERVER OF THE TWIN CITY AMATEUR ASTRONOMERS Volume 42, Number 7 July 2017 INSIDE THIS ISSUE: 1«Editor’s Choice: Image of the Month – Messier 109 2«President’s Log 3«Calendar of Celestial Events – June 2017 3«New & Renewing Members/Dues Blues/List/Forum 3«Subscribing to Our E-Mail List & Forum 4«Planets and Bright Stars in Evening Mid-Twilight 5«This Month’s Phases of the Moon 5«Local Sunrise and Sunset Times for June 5«AstroBits – News from Around the TCAA 8«Profiles in Amateur Astronomy: Tim Stone 10«TCAA Photo Gallery 12«AstroBits (continued) 12«Education and Public Outreach for June 2017 13«Introduction to Amateur Astronomy 13«First Sidewalk Astronomy Viewing Session 14«July 25th Fifth PVS of 2017 EDITOR’S CHOICE: IMAGE OF THE MONTH – MESSIER 109 14«Remaining PVS for 2017 15«Camp Ondessonk Reminder July’s Image of the Month is by Jim Gibbs. Jim writes, “It is hard 15«TCAA on Facebook and Twitter to let clear skies pass by without thinking about being outside 15«HowTimeFlies observing or imaging. This is exactly what I did on May 12th when I 16«Treasurer’s Report for June 2017 captured Messier 109 at the SGNC. I also capture C/2015 V2 aka 17«Renewing Your TCAA Membership Comet Johnson. I haven’t processed Comet Johnson yet as it will require a bit more processing time since it moves very quickly and then makes things much different from stacking regular objects. Imaging Messier 109 had its own challenges, the nearby star Phecda, which is one of the stars that define the bowl of the Big Dipper is pretty bright. Also, the Moon rose at about 11:30 but wasn’t too much of an impediment. Messier 109 (also known as NGC 3992) is a barred spiral galaxy exhibiting a weak inner ring structure around the central bar approximately 83.5 ± 24 million light-years away in the constellation Ursa Major. M109 can be seen southeast of the star Phecda (γ UMa). Messier 109 was discovered by Pierre Méchain in 1781. In 1783 Charles Messier catalogued NGC 3992 as his 109th object. Between the 1920s through the 1950s, it was considered that Messier objects over 103 were not official, but in later years the additions became more widely accepted. David H. Levy mentions the The TCAA is an affiliate of the Astronomical League. For modern 110 object catalog while Sir Patrick Moore gave the original more information about the TCAA, be certain to visit our to 104 but has M105-M109 listed as an addendum. By the late club website. 1970s, as all 110 objects are commonly used among astronomers as they still are today. Copyright © 2017 TCAA 1 All rights reserved. Vol. 42, No. 7 The OBSERVER of the Twin City Amateur Astronomers July 2017 In March 1956, supernova 1956A was observed in M109. SN 1956A was a type Ia supernova in the southeast part of the galaxy, glowing at magnitude 12.8 to 12.3 at its The OBSERVER maximum. SN 1956A has been the only supernova observed in M109 since its discovery. is the monthly electronic newsletter of Twin It is also by far the most distant object in the Messier Catalog, followed by M91. M109 City Amateur Astronomers, Inc., a registered 501(c)(3) non-profit educational has three satellite galaxies (UGC 6923, UGC 6940 and UGC 6969) and possibly might organization of amateur astronomers have more. interested in studying astronomy and Detailed hydrogen line observations have been obtained from M109 and its sharing their hobby with the public. satellites. M109's HI distribution is regular with a low level radial extension outside the TCAA OFFICERS & CHAIRPERSONS stellar disc, while at exactly the region of the bar, there is a central HI hole in the gas distribution. Possibly the gas has been transported inward by the bar, and because of PresIdent & Director/Property Manager Tim Stone 309-531-2401 the emptiness of the hole no large accretion events can have happened in the recent [email protected] past. Vice PresIdent & Director/PublIcIst Source: en.wikipedia.org/wiki/Messier_109 Darren Erickson 309-336-0103 [email protected] Treasurer & Director/RegIstered Agent Dave Osenga 309-287-0789 PRESIDENT’S LOG [email protected] When Earth passes through the point in its orbit Secretary & DIrector/HistorIan/EdItor where its equatorial plane bisects the oblate spheroid Carl J. Wenning 309-830-4085 of the sun, we call that a Solstice. When that happens [email protected] in June, we northern hemisphere dwellers call that the Director & ObservIng Programs Coord. Summer Solstice. Of course, our southern hemisphere Jim Gibbs 847-809-2232 neighbors see this in quite the opposite light. It's [email protected] winter down there. With the heat we had earlier in AstronomIcal League Correspondent June, we probably wish it was winter up here, too! Robert Finnigan 309-846-9533 [email protected] The Summer Solstice marks the official beginning of Summer, when we do much of our outdoor work Webmaster and outdoor play. Summer is the least optimal time for astronomy, with its relatively Lee Green 309-454-7349 [email protected] short nights, and hot air playing seeing games with our telescopes. This summer finds us at TCAA working to secure the necessary permits from DeWitt LightIng EducatIon CoordInator County to construct our new observatory facilities east of Waynesville. We attended the Lisa Wentzel unlisted number th [email protected] first of three hearings on June 20 , a hearing held by the DeWitt County Regional Planning Commission. We presented our proposal, and I'm happy to report the MembershIp CoordInator Tom Willmitch 309-846-2423 commission approved our plan unanimously and enthusiastically. The commission asked [email protected] lots of questions, many of which were less about our proposal and more just out of Technology Coordinator curiosity about what we do and why we do it. We were happy to answer their questions, Justin Meyer 630-649-0611 and they voted to approve, with smiles and obvious excitement. It was great to see. [email protected] So, why do we desire to build in DeWitt County? Bloomington's expanding light The OBSERVER dome is one of the primary reasons. The site we are negotiating for is one shade darker on the light pollution map on ClearDarkSky.com. It is rated a 4 on the Bortle Scale, Carl J. Wenning, Editor in Chief Paul Pouliot, Assistant Editor rather than the 4.5 rating the Sugar Grove Nature Center is given. ClearDarkSky.com adds commentary about what to expect from a sky with a 4 rating: " Zodiacal light seen Submission deadline end of each month. on best nights. Milky Way shows much dark lane structure with beginnings of faint bulge MEMBERSHIP DUES into Ophiuchus. M33 difficult even when above 50 degrees. Limiting magnitude about Individual Adult/Family $40 6.2 to 6.5." Full-time Student/Senior $25 So, stay tuned. There will be a steady stream of information in my President's Log in (Senior status equals ages 60+) The OBSERVER for quite a few months to come! To join, send your name, contact info and dues payment to Dave Osenga, TCAA Clear and dark skies! Treasurer, 1109 N. Linden St., Normal, IL Tim Stone, President 61761-1471. Copyright © 2017 TCAA 2 All rights reserved. CALENDAR OF CELESTIAL EVENTS – JULY 2017 NEW & RENEWING MEMBERS MORNING PLANETS (7/15): Mercury, Jupiter, and Saturn The following individuals have paid dues for new or renewed memberships as of June 23rd, 2017. (Others who EVENING PLANETS (7/15): Mars, Venus, Uranus, and Neptune paid after that date will appear in the August 2017 issue of The OBSERVER.) 03 Earth at AphelIon – The Earth is farther from the sun today than at any other time of year. Its distance is 1.01668 astronomical units, or 1.668% greater than its average Matthew Will, Roy Lawry, and Tim Stone distance. This bit of information alone should dissuade people from the mistaken belief that the seasons are caused by the changing Earth-Sun distance. If that were the UES LUES case, we would be experiencing winter at the moment! D B 08 Full Moon – The Moon will rise at sunset and set at sunrise. If you have received a “your dues are due” statement This full moon was known by early Native American tribes along with the email that brought you this issue of The as the Full Buck Moon because the male buck deer would OBSERVER, please remit your dues to Mr. Dave Osenga, begin to grow their new antlers at this time of year. This TCAA Treasurer, 1109 N. Linden St., Normal, IL 61761- moon has also been known as the Full Thunder Moon and 1471. Dues are currently $25 for seniors (60 years of age the Full Hay Moon. and over) and $40 regular. 16 Last Quarter Moon – The waning, half-lit moon rises SUBSCRIBING TO OUR E-MAIL LIST & FORUM around midnight and sets around midday. By subscribing to a group’s mailing list, you will receive 23 New Moon – Sets at sunset and rises at sunrise; not visible. email messages from the group so you won’t have access to the group’s web features (like photos, files, links, polls, 29 Delta AquarIds Meteor Shower – The Delta Aquarids is an calendar, etc.) unless members activate it later. The club average shower that can produce up to 20 meteors per has an open email listserv. It is known as the TCAA hour at its peak. It is produced by debris left behind by Yahoogroups listserv.
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