ORION Trapezium, December 2025, Vol. 51, Issue 12.

Vol. 51, Issue 12 https://zenodo.org/records/17873056 Fri 12 Dec 2025 JD2461022 ORION | Trapezium A Monthly Publication of the ORION Astronomical Society Roane State provides a cheery display for the Holiday Season. Note the red giant star at top. Imaged Wed 19.XI.2025 Oak Ridge TN Table of Contents 3 4 6 8 17 28 29 30 35 36 37 43 45 65 69 72 73 75 77 78 80 81 82 84 Ab initio Page Three Astronomy: “Festival of the Winter Solstice” ……….………..…………….. About ORION and TRAPEZIUM ……..……….……………...…………....……................ Messages from ORION President’s Message - Don Spong …………………………………….....….……..……..… TAO Director’s Message / Observatory Way - David Fields .…………………....……… ORION Board Meetings ElCantarito - Rob Fowler ……………………………..…….….. ORION Monthly Meetings ORION Monthly Meeting Format ….……………..……………….…….….……....……… ORION Meeting 12 Dec 2025: Festival of the Winter Solstice and Christmas Dinner ORION Last Month: Lunar Impact Flash Project - Richard Piety .…..……….....….… Events and Calendars, Sky Maps and Observing Sessions Star, Moon, Comet and Meteorgazing at TAO in 2025 ……….………..….…..….….... TAO Public Stargazing: A Note Regarding Scheduling and Access in 2025 ..…..……. Public Stargazes in Nov & Dec 2025; TAOCalendars…………….…...……...…….……. Public Stargaze of 15 Nov 2025 - Ted Barnes ………………………………………...…… Two occultations in one night: 1234 Elyna and 1695 Walbeck (Sun 23 Nov 2025) - Ted Barnes and Richard Piety …………………………….…….………..…………… Public Stargaze of 06 Dec 2025 - Ted Barnes ………………………………………...…… The Evening Sky Map / Dec 2025 .…………………………….………….……..………...... Astrophotography Lunar Maria - Noah Frere ..………………………………………...………………….….… Reflection Nebula IC 5076 in Cygnus - Don Spong ………..…………….…………….. Appendices Astronumerology ……………………………………..…………………………………..…… The 80 Brightest Stars ………………………………….……………………………..……… Notable Star-Pair Angles …………………………..…………………………….…..……… Exeunt Poetica .………………………………………….…..………………….….……………..…… ORION and TAO General Information (and links) ………………………………..……... Trapezium back issues online …………………………………….……….……..…...…..… Fin du Journal …….…………………………………………………………………....…….. 3 3rd Annual ORION Hello ATTENDEES! This is a quick reminder of what is planned, what is needed, and how you might contribute if desired. First, please advise us if you plan to attend, and how many will likely be in your party, so we can make the appropriate arrangements. The dinner will be on Friday 12 Dec 2025, at the High Places Community Church, Grove Center in Oak Ridge, with setup from 6:00 pm, and dining to begin soon afterwards. We would appreciate people signing up to bring main dishes to be shared, as well as side dishes such as salads, veggies, pastry, dinner rolls, etc. Serving utensils will also be appreciated. We will provide “picnic style” plates, cutlery and napkins, but we encourage people to bring their own settings If they wish to enjoy a more festive experience. Hello ATTENDEES This is a quick reminder of what is planned, what is needed, and how you might contribute if desired. First, please advise us if you plan to attend, and how many will likely be in your party, so we can make the appropriate arrangements. The dinner will be on Friday 12 Dec 2025, at the High Places Community Church, Grove Center in Oak Ridge, with setup from 6:00 pm, and dining to begin soon afterwards. We would appreciate people signing up to bring main dishes to be shared, as well as side dishes such as salads, veggies, pastry, dinner rolls, etc. Serving utensils will also be appreciated. We will provide “picnic style” plates, cutlery and napkins, but we encourage people to bring their own settings if they wish to enjoy a more festive experience. Signup link: https://www.perfectpotluck.com/meals.php?t=RGLT4470 The ORION Astronomical Society is a science and astronomy group founded in April 1974 by scientists from the United States Department of Energy facilities at Oak Ridge, Tennessee. We primarily serve the communities of Oak Ridge and Knoxville and the counties of Anderson, Knox, and Roane. ORION’s mission is to support scientific research, teaching, and astronomical activities in East Tennessee. We hold monthly public meetings at the Oak Ridge RSCC Campus, and are active at TamkeAllan Observatory (TAO), hosting public events, sharing knowledge of the skies, and helping to provide intellectually stimulating programs. ORION works to share the wonders of the cosmos and the culture of science. ORION members include scientists, engineers, technicians, IT experts, artists, students, and others with varied talents and expertise. Over half of ORION members own telescopes, many are amateur radio operators, and some have expertise in astrophotography. ORION has working relationships with several organizations, including museums and other amateur astronomy groups. Membership is open to individuals who will actively contribute their time and ideas. The annual membership fee is $20, and student discounts are available. There is no charge for our newsletters and publications, or for participation in most ORION activities. TRAPEZIUM is a monthly publication of the ORION Astronomical Society. The issue date is the Friday preceding the monthly ORION meeting, chosen to provide timely information regarding the planned Program. From March 2025 we have attempted to produce a somewhat shorter version of the Trapezium, which would still include important information regarding the monthly ORION presentation, as well as information regarding Public Stargazes and other notable events relating to ORION and TAO. The information removed includes a list of the brighter active supernovae, an observers’ equipment section, and personal “Meet ORION” mini-biographies. However we concluded that some components, such as a separate Astrophotography section, are so important for a publication on amateur astronomy that one really cannot justify excluding them. So, the new Trapezium is only somewhat shorter, by about 20 pages. ORION Board and Officers: President: Don Spong VP and Program Chair: David Fields Secretary, IT: Rob Fowler Treasurer: Bob Edwards Editor: Ted Barnes ORION Speaker POC: Richard Piety Member w/o Portfolio: Art Allison 4 Messages from ORION We are approaching the Winter Solstice, occurring at UTC 15:03 on December 21. Days will gradually start becoming longer after this, so it’s good to take advantage of our long nighttime viewing hours this month while they last. This month we have our 3rd Annual Orion Festival of the Winter Solstice and Christmas Dinner on Friday, December 12 (described in more detail later). We’ve had several successful stargazes at Tamke-Allan. Also amazing work continues to come out of our occultation efforts – see the article by Ted Barnes and Richard Piety later in this issue. I would finally add that I have recently acquired a new telescope (a 130mm Stellarvue refractor), so expect some cloudy weather; sorry about that! December 4 was the full moon (known as the Cold Moon) and the new moon will be on December 20, with December 20-21 a good dark sky weekend. A variety of planets are now visible, including Neptune, Saturn, Jupiter and Uranus. December meteor showers include the Geminids early in the morning of December 14, the Ursids on December 21, and the Quadrantids on December 31. Comets include the mysterious 3I/Atlas (magnitude 10.8) visible in the early morning, and C/2025 T1 Atlas (magnitude 9.6) visible in early evening twilight. A variety of deep space objects are in good viewing position for December. Starting first with the star clusters, we have: M45 (the Pleiades) in Taurus, M38 (Starfish) in Auriga, M37 (Salt and Pepper) in Auriga, M36 (Pinwheel) in Auriga, the Hyades in Taurus, the double cluster NGC 869 and NGC 884 in Perseus, and M103 in Cassiopeia. Nebulas include: M42 (Orion Nebula) in Orion, NGC 2237 / C49 (the Rosette Nebula) in Monoceros, IC 410/ NGC 1893 (Tadpole) in Auriga, IC 1848 / IC 1805 (Soul/Heart) in Cassiopeia, NGC 1499 (California) in Perseus, M76 (Little Dumbbell) in Perseus, NGC 7293 (Helix) in Aquarius, and M1 (Crab) in Taurus. 6 President’s Message (cont.) - Don Spong Galaxies include: M31 (Andromeda) in Andromeda, NGC 891 / C23 (Outer Limits) in Andromeda, M33 (Pinwheel) in Triangulum, NGC 253 (Silver Dollar) in Sculptor, M77 (Cetus A) in Cetus, NGC 1300 (barred spiral) in Eridanus, NGC 1232 (spiral), also in Eridanus, and M74 (spiral), the Phantom Galaxy in Pisces. So with all of these great choices (+ maybe a few occultations), we invite you out to observe! 7 President’s Message (cont.)(cont.) 8 David Fields December 2025 The photo on the left shows our new road sign for Roane State’s Tamke-Allan Observatory (TAO). Traveling West on Caney Creek Road from Roane County Park, the sign appears on the left just after crossing Joiner Hollow Road. TAO Director’s Message / Observatory Way : December – our busiest month TAO offers Public Stargazes to the community on the 1st and 3rd Saturday of each month, weather permitting. From mid-October through the winter, we open by 7:30 pm and continue nominally until 10:30 pm (or later when the sky and attendance encourage this). Opening time changes according to the season, and a good guide is to arrive at the observatory about sunset, when the weather is encouraging. Our stargazes are supported by local astronomy clubs, especially ORION members and friends, and benefit our students and community. Our TAO stargazes are usually well-attended, with a full classroom of visitors for evening astronomy lectures. TAO Public Stargazes and Special Events The sun has lately been active with major sunspot activity. We’ve observed several aurorae from TAO and anticipate arrival of a coronal mass from the sun, perhaps on Dec. 9. We’re building up from a very active year of observing “asteroid occultations,” with an observing event planned for lunar flashes (weather permitting) on the night of (or perhaps three successive nights starting with) Dec. 11/12. Our annual event, this year it being the ORION 2025 Festival of the Winter Solstice and Christmas Party, on the evening of Friday Dec. 12. (See pp.3 and 34.) Don’t miss it! Observatory Way (cont.) The sun has lately been active this year, with major sunspot activity. We’ve observed several aurorae from TAO, and anticipate the arrival of a (thin, gaseous, ionic) coronal mass from the sun, perhaps on the evening of Dec. 9. My photo of the sun (at right), taken at the International Friendship Bell on Nov. 5, shows some interesting sunspots. One month after the early November solar event, a new solar event (on Dec. 6), looks possibly more consequential. The above photo (from Space weather.com) shows the scale compared to the sun: Aurorae Expected? Observatory Way (cont.) International Friendship Bell (IFB) Stargazes – where to setup telescopes? In the future, we’ll try to set up the larger scopes in a closer parking lot, located just to the South of the bell. It’s a short walk across the bridge up to the telescope lot, so I hope that this is more convenient for the astronomers with larger telescopes. Finally: … Don’t miss our Festival! (see pp.3 and 29.) This is a summary of topics discussed recently at the weekly (Monday 1 pm) ORION Board Meeting held as a regular working lunch at ElCantarito restaurant in Oak Ridge. Notes as contributed in Stardate format by Sec. Rob Fowler. Stardate: 2025.03.31 In attendance were Robert Fowler, Ted Barnes, David Fields, Art Alison and Don Spong. Discussed delays on new dome report due to committee participant availability. Discussed possible going to TAO Tuesday night. Discussed next speaker is not firm for April's meeting. Discussed voting for officers at the next ORION Meeting. Discussed the next Friendship Stargaze and date for same, 8th possibly. Discussed possibly coming up with cloudy night entertainment for Friendship stargaze. Discussed Wordsworth poem about telescopes. Discussed potential security cams for TAO. Stardate: 2025.04.07 In attendance were David Fields, Art Alison, Ted Barnes and Rob Fowler. Ted discussed the data acquired from his Arduino/LED test. David discussed a mount having the ability to track asteroids via PHD2. David discussed the Friendship Stargaze is 7:30pm Tuesday. Discussed needing pics of new concrete pads at TAO. Stardate: 2025.04.14 In attendance were David, Ted, Art and Rob. Ted discussed results of the 785 Zwetana occultation. After a long and dramatic story, Ted revealed a successful capture. Noah is reaching out to Joe Baldwin about next month's presentation. Ted discussed quantum field theory using functional methods. Stardate: 2025.04.21 In attendance were David Fields, Ted Barnes, Art Alison, Noah Frere and Rob Fowler. Ted discused how to use AnyDesk and log in unattended. Ted discussed a planetary occultation, Mars vs a 9th magnitude star on May 6th at 1 am. David discussed progress he is making with a Meshtastic receiver. Mention of 4 visitors who showed up at TAO and new member Kevin Wilson. David brought up calendar access .Discussed problem with rotation of glow dome lid. Watch for migration of wheel axles. One axle migrated in and caused the lid to bind. 17 ORION Board Meetings ElCantarito - Rob Fowler Stardate: 2025.04.28 In attendance were David Fields, Ted Barnes, Art Alison, Kevin Wilson, John Cliff and Rob Fowler. Briefly mentioned domes on CloudyNights.com. Ted discussed upcoming Mars/Star occultation and relevant challenges. HD 74058 vs Mars just after midnight 00:44 night 5th/6th morn. TAO Stargaze beginning at May 3rd 8pm. Friendship Stargaze possibly May 6th. Briefly discussed avoiding Feynman's van. Shared astrophotos. Discussed potentially going to TAO tonight & Noah's class. Stardate: 2025.05.05 In attendance were David Fields, Art Alison, Ted Barnes, Kevin Wilson, and Rob Fowler. David asked if we have a set program for May. That remains unclear. Ted contacted Noah to confirm. We await a reply. Ted mentioned the next annual IOTA meeting is possibly going to be in New Mexico in Oct. Stardate: 2025.05.12 At 11am David, Ted & Art met at the Library and made a first pass as setting up a display case for the club. Rob joined later. It was artistically done, decorated with a small telescope, some antique books, and astrophotos. Discussed whether Kevin might give the May lecture and what topics he has ready. He agreed to speak on the topic of stellar spectroscopy. Ted mentioned the next possible occultation on the early morning on 5/21/2025. Stardate: 2025.05.19 In attendance were Don, David, Ted, Art, Kevin, and Rob. Kevin brought up Benjamin Baniker as a potential lecturer. Rob announced that the most recent lecture is on YouTube. Star Date: 2025.05.26 In attendance were Don, Dave, Art & Rob. David suggested improvements to the Meade's power supply in hopes of reducing noise, higher amperage power supply, adding ferrite cores. Dave discussed getting a construction party to begin construction on the Dob shelter. Discussed parking issues at TAO. 18 ORION Board Meetings (cont.) Stardate: 2025.06.02 In attendance were Don, David, Bob, Art, Juan, Kevin and Noah (and Sunny). We met early at the library to discuss the current and new display box. Discussed meeting again, tomorrow (Tuesday). David suggested Wednesday night 8:30pm as the next Friendship Stargaze. Kevin suggested meeting at TAO to look at the Meade's encoder. Noah suggested reaching out to Gareth Davis to see if he has any potential acquaintances for another lecture. Don asked about the new dome project. David responded with a tale of woe regarding the Roane purchasing project. Stardate: 2025.06.09 In attendance were Don, David, Art and Rob (joined by John Rather). David purchased 2 coin cells for the Celestron CGM mount. He also purchased a few ferrite cores to suppress noise from the power supply. Ted expressed an interest in having help with this months Trapezium. Discussed the new optical telescope coming online in the Atacama Desert. Briefly mentioned the library displays and Oak Ridge street lighting. Noah mentioned that Gareth Davis can give the next lecture. Stardate: 2025.06.16 In attendance were Don, Kevin, Art and Rob. Rob showed his submission for the AMSE poster. Kevin & Don discussed PixInsight. We confirmed Kevin is speaking this month. Kevin discussed the Astronomical League and it's various programs, and contests for various achievements. Stardate: 2025.06.23 In attendance were Don, David, Ted, Art, Kevin and Robert. Due to crowding at the table, no notes were taken. Stardate: 2025.06.30 In attendance were David, Ted, Art, Kevin, and Rob. Don sat in for a short while. Ted & Rob discussed results of the occultation via a new process. Kevin presented a new ORION Logo. Kevin announced he will be moving out of the immediate area. 19 ORION Board Meetings (cont.) Stardate: 2025.06.30 David presented Kevin with a gift ORION T-Shirt. David brought up shop type measurements he intends to do on the Meade. The group went on discuss various theoretical topics. Mention of 4 visitors who showed up at TAO and new member Kevin Wilson David brought up calendar access. Discussed problem with rotation of glow dome lid. Watch for migration of wheel axels. One axel migrated in and caused the lid to bind. Stardate: 2025.07.07 In attendance were Don, Ted, David, Art, Rob and visitor John Rather. Conversations opened with Ted discussing digitizing the occultation substacking project. David discussed a lightstrip project and possible application in the dome. Ted collected info for this month's Trapezium. David discussed attendance at the Sat July 5 Public Star Gaze, was 12, give or take. David discussed the testing we did on the Meade and saw no alignment errors. Stardate: 2025.07.14 In attendance were David, Ted, Art and Rob. Ted shared some mathematical analysis of the recent occultation data. David brought up potential dates for the next Friendship Star Gaze. We discussed the next ORION lecture and whether to zoom it or not. We discussed possibly having a news feature at ORION lectures. Stardate: 2025.07.21 In attendance were David, Don, Ted, Art, Rob... and guest John. Dave led the discussion with Rob's absence. Dave mentioned that Saturday night’s public star gaze was successful, with around 8 visitors. We discussed the recent lecture and the unplanned move to the computer classroom. The general consensus is that it went well. Dave will be away on August 2nd, the next star gaze. Ted brought up details of participation in the Tuesday night / Wednesday morning occultation. Stardate: 2025.07.28 In attendance were David Fields, Ted Barnes, Art Alison and Rob Fowler. We will probably have a public star gaze at TAO on 8/2/2025, public or private depending on weather and Noah's decision. 8/12/2025 Perseid meteor shower a probable star gaze. 20 ORION Board Meetings (cont.) Stardate: 2025.07.28 Our Library display will expire soon. David will inquire if we can keep it another month or if we need to clean it out this month. If it has to come down, Ted & Rob have agreed to remove the contents. Stardate: 2025.08.04 Present were Don, Ted, Rob, Art and guest John Rather. Ted shared his most recent results and submission to IOTA that we have been re-evaluating. Don won’t be present for the August ORION meeting. We believe John Cliff is August's speaker. We discussed various lightning phenomenon We also discussed the Big Bang theory and John Rather's book. Stardate: 2025.08.11 Present were Don, Ted, David, Art, Rob and guests Richard Piety and John Rather. Ted reported on some of his recent results with IOTA’s python scripts and graphing. Rob reported on visiting Lily Bluff's Star Party at Wartburg, where he met Joshua, Gareth and Owen. Don told us of a new 16 bit color astro camera he just bought, a ZWO ASI2600MCP. John told us of an experience with a pro telescope. Richard just bought a QHY174M-GPS camera for recording timed asteroid occultations. We discussed weather regarding the Perseid meteor / stargaze, 8:30pm Tuesday, but the weather is deteriorating. There is a possible occultation on 8/23/25. Star date: 2025.08.18 In attendance were Ted, David, Art, Rob and guests John Rather and Richard Piety. David spoke to Courtney at AMSE about our ORION display. We have been invited to keep it set up for a while longer. We discussed possibly tracking 3I/ATLAS to get a pic, having an unscheduled observation evening. Star Date: 2025.08.25 In attendance were Dave, Ted, Richard and Rob. Ted shared the results of the recent asteroid occultation. David visited the K-25 interpretive center and described the layout. He said they are interested in us bringing a star party to that location. David noticed that one of the new pads in collecting water. Rob suggested a modified a port-a-potty as a camouflage telescope cover. Calling it "Astro-Johnny: Smelling like Roses!" 21 ORION Board Meetings (cont.) Star Date: 2025.09.01 In attendance were David Fields, Ted Barnes, Art Alison and Rob Fowler. And visitor David Allred. David Fields fixed the internet at TAO and treated several ant colonies. The skies were good from 9pm to Midnight. Discussed an upcoming eclipse in Sydney Australia in 2 years. Ted spoke to the programmer of Occult Watcher [Hristo Pavlov] who helped him troubleshoot a bug. IOTA Annual meeting is next week on zoom. Star Date: 2025.09.08 In attendance were David Fields, Ted Barnes, Rob Fowler, Don Spong, Art Alison and Richard Piety. We has a successful Moon-gaze at TAO last night. Ted discussed his occultation studies. He was successful with one last night Sunday 2025.09.07. Richard attempted it too but has not analyzed his results yet. We had a new guest last night, Art’s friend Deirdre Akin. She joined the astro-luncheon as well. Star Date: 2025.09.15 In attendance were David Fields, Ted Barnes, Don Spong, Rob Fowler and Richard Piety. We discussed concerns over who is coordinating speakers going forward. Tentatively, we believe Gareth Davies is our September speaker. We discussed news about the cosmic interloper 3I/Atlas and new spectral data. 22 ORION Board Meetings (cont.) ORION Board Meeting at the ElCantarito Mexican Restaurant, Oak Ridge, Mon 22 Sep 2025. L to R: Ted Barnes, David Allred, David Fields, Richard Piety, Rob Fowler, and Gareth Davies. Star Date: 2025.09.22 In attendance were David Fields, Ted Barnes, Robert Fowler, Richard Piety and guest, David Alred. Gareth Davis, Art Allison, and Don Spong arrived later. Ted and Richard discussed results of a recent occultation. Richard caught 2 new occultations recently. David expressed concerns over the success of last Saturday's Stargaze. He felt distracted and so thought it did not go well. But several of us thought it went very well. Gareth Discussed cosmic interloper 3I/Atlas, and its tail having recently turned green. Richard Piety confirmed that the ORION website is badly out of date. To support Public Star gazes, David discussed having teams of 2 to operate the Meade. Gareth talked about an astrophysicist, David Butler, who has a Youtube channel. Star Date: 2025.09.29 In attendance were Don, Ted, David, Richard, Art and Robert. Ted told us about his visit to New Mexico and the skies at Cloudcroft. David asked about an abstract for October’s guest speaker, Joshua from OBED. We discussed possibly meeting at TAO on Wednesday or Thursday. Star Date: 2025.10.06 In attendance were David Fields, Don Spong, Ted Barnes, Rob Fowler & Art Allison. David suggested we create something as a giveaway to members and students. He suggested a plastic ruler to help people understand angles. He also discussed making a custom planisphere. We discussed using Night Sky Network to coerce dues compliance. Art took up the challenge of creating a new giveaway / print project. Although this month’s speaker is confirmed, no details have been communicated. Etymology needed for the expressions “cattiewumpus” and “whackadoodle.” ORION Board Meetings (cont.) 23 Star Date: 2025.10.13 In attendance were Don Spong, Ted Barnes, David Fields, Rob Fowler and Richard Piety. •Winter Solstice is December 21, recommending having our winter solstice party on Saturday, Dec 20th. Possible locations: High Places Church. Don also suggested El Toro, a new Mexican restaurant in Oak Ridge. There is also a Chinese buffet, Hong's Asian Bistro, near Kroger's that might be possible. •David offered suggestions about a gift for TAO members. He showed an eclipse viewer he designed. •We discussed problems with the Meade mount and possible solutions. We also discussed adding a guide scope. •We discussed having a new Speaker POC and potential speaker for November. Richard volunteered to be acting Speaker POC for a while and see how it works out. Star Date: 2025.10.20 In attendance were David, Don, Art and Rob. •Don got a photo of Comet C/2025 R2 Swan at the recent stargaze. We had a large turnout at the star gaze because of a homeschool group. Attendance was around 30 or so. •Rob & Ted plan to go to TAO tonight to observe a 3am occultation. •We discussed plans for a Christmas/Solstice party. David and Don will check on the availability of 2 restaurants. •We discussed who is the key person for each of the various ORION social media assignments. •There is no official speaker chosen for November's meeting. ORION Board Meetings (cont.) 24 Star Date: 2025.10.27 In attendance were David Fields, Don Spong, Ted Barnes, Rob Fowler and Art Allison. Ted shared results from the most recent asteroid occultation, asteroid Chimaera. Considering 12/17 for the xmas party. Don & Rob shared details of 2 locations. David is designing a 3d joke. It's deep. Star Date: 2025.11.03 In attendance were Dave Fields, Don Spong and Robert Fowler. •Discussed was the weather for a planned visit to TAO tonight. Agreed on a cut off of 4:30 pm to decide if weather permits. •David showed a printable planesphere for a youth project. •Don mentioned a new mini clamshell dome designed for small telescopes like the see-star. We also discussed how a See-Star is designed to be used remotely. •Rob asked if we have a speaker for this coming lecture. No specific was forthcoming. Star Date: 2025.11.11 In attendance were David Fields, Ted Barnes, Richard Piety, Rob Fowler, Don Spong, and guest John Rather. Art joined late. •We met at noon in deference to the "Lunar Flashes" zoom call at 3pm. Richard shared some general info about their mission. •Richard also mentioned a potential speaker, Fred Schumacher. •Ted bought a 2 inch moon filter to aid at public star gazes. •Richard and David discussed the general state of our web presence. ORION Astronomy has a website & a facebook page and Tamke-Allan Obs also has a website & facebook page. •We decided to go back to the bring your own beverage & covered dish for the xmas/solstice party. Possible dates? Sat 12/13. ORION Board Meetings (cont.) 25 32 ORION Last Month (cont.) The presentation consisted primarily of a recorded Zoom talk on LIFs to likely participants by Detlef Koschny, LGC Project Director and Prof. of Engineering at the Technische Universität München (TUM). Detlef is explaining things from the insert at center right. 33 ORION Last Month (cont.) Richard receives his ORION Speaker’s mug from Bob Edwards after the presentation. Events and Calendars, Sky Maps and Observing Sessions We enthusiastically invite visitors to attend our Public Stargaze events, held at our darksky site, the Tamke-Allan Observatory (TAO) near Kingston, Tennessee. These events are intended especially for visitors, so our buildings and facilities will be open, and there will be astronomy talks as well as public skywatching. In Jan-Jun 2025 we plan to hold fixedcalendar public Stargaze events on the 1st and 3rd Saturday of each month. These weekend events are especially appropriate for families. We also hold public special events, such as a “Full Moonrise,” with associated Moon Music, and the occasional comet watch. The annual Perseid Meteor watch in mid-August is especially popular. The precise dates of many of these events depend on the local weather conditions, and cannot be specified definitively long in advance. As an approximate guide, see the TAOCalendar pages following. Once a date is finalized we usually confirm it through the ORION online message site ORION [email protected]. Likely and unlikely dates for TAO events may be inferred from the weather predictions at TAO by Clear Sky Charts (cleardarksky dot com) and Astrospheric (astropheric dot com). Please confirm event dates before proceeding to TAO. In view of the rather challenging approach road to TAO, “Observatory Way,” first-time visitors should plan to arrive before dark. Driving instructions are given at: https:// www.roanestate.edu/pages/obs/visit.htm Some instructions follow, since people may be unfamiliar with procedures for stargazing at a dark-sky site. ORION members are invited to arrive early with their telescopes and mounts, to prepare for evening observing and to share refreshments. Please bring a red flashlight, or a headband with a red-light option. Visitors who wish to acquire red lights or red-light headbands for observing may find them at many commercial amateur astronomy sites, such as https:// www dot high pointscientific dot com. The “Lepro LE” LED Headlamp, model 3200008, available from Amazon for about $10 (Aug. 2024) is a personal favorite. This is rechargeable and has separate red and white led buttons, with several brightness settings. A caution: For amateur astronomy, brighter lights are NOT preferred, and WHITE lights are highly discouraged. Please use only red lights while the Stargaze is in progress. Parking is available on site; on entering TAO stay to the right, and please use the parking area below and right (Southwest) of the TAO buildings and observing area, near the treeline. And PLEASE NO HEADLIGHTS ON SITE. Visitors are encouraged to interact with ORION astronomers who have set up and may be operating telescopes and other astronomical equipment. We enjoy public discussions, and regard this sharing of information as a primary goal of our organization. Visitors are welcome to coffee and other refreshments. v. 4 Mar 2024 (Trapezium) Star, Moon, Comet and Meteorgazing at TAO in 2025 TAO Public Stargazing: A Note Regarding Scheduling and Access in 2025 In 2025 we are reverting to an earlier schedule of having our Public Stargaze nights on every first and third Saturday. Of course this assumes good weather; if the weather is not suitable, a changed schedule will be announced on the group site ORIONastronomy @ groups.io. We decided that the previous (2024) schedule of a once-monthly Public Stargaze was insufficient, and having a Moon visible in some phase other than close to New gives our visitors an obvious and interesting object for viewing. During Daylight Savings Time (mid-March through early November) we plan to hold our Public Stargaze events over the hours of approximately 8:00 pm - 11:00 pm, with some nominal variation. If it is already dark when you arrive, please dim your headlights on the TAO grounds, follow the right branch of the access road, and park to the right of the TAO building, near the treeline. Note: Parking in or near the elevated flat observing area at the front (East) of the TAO building is reserved for astronomers who are bringing their equipment. Additional information for visitors may be found on the previous page and following two pages of this issue. 36 37 TAO Public Stargazes in November: Sats 01 & 15 Nov 2025 Sunset 6:43 pm Civ dusk 7:10 pm Ast dusk 8:10 pm Moonrise 4:23 pm Moonset* 2:31 am *02 Nov Sat 01 Nov 2025 Waxing Gibbous Moon. Bright Moon during this event. Sunset 5:32 pm Civ dusk 5:59 pm Ast dusk 7:01 pm Moonrise 2:56 am Moonset 3:04 pm Sat 15 Nov 2025 Waning Crescent Moon. No Moon visible during this event. Moon illum. 79% Moon illum. 27% TAO Public Stargazes in December: Sat 06 & 20 Dec 2025 Sunset 5:25 pm Civ dusk 5:54 pm Ast dusk 6:57 pm Moonrise 7:10 pm Moonset* 10:35 am *07 Dec Sat 06 Dec 2025 Waning Gibbous Moon. Bright Moon during this event. Sunset 5:29 pm Civ dusk 5:58 pm Ast dusk 7:01 pm Moonrise 8:31 am Moonset 5:52 pm Sat 20 Dec 2025 Waxing Crescent Moon. No Moon visible during this event. Moon illum. 96% Moon illum. 0% TAO Calendars Jan-Jun & Jul-Dec 2025; Nov & Dec 2025 The principle public events for visitors at TAO are the Public Stargazes, held at TAO during 2025 on the 1st and 3rd Saturday of each month. These are listed in the “Public Fixed Events” TAO Calendar for six month periods, currently Jul-Dec 2025. These appear on the two pages immediately following. Additional notable events will be included in monthly “Special Events” TAOCalendars. These include public events that do not have a fixed date long in advance, such as the International Friendship Stargaze in Oak Ridge, and special TAO events such as Asteroid Occultations, Meteor Showers, Full Moonrises, Lunar (and other) Eclipses, Comet Watches, and perhaps the occasional musical event. These “Special Events” calendars for the current and subsequent months appear after the two six-month “Public Stargaze” calendars. The facilities in the TAO buildings onsite will be open to the public during the “Public Fixed Events,” and will also usually be available when TAO is open to the public for some of the “Special Events.” Please inquire regarding whether TAO will be open to the public for any “Special Event” you may wish to attend, since some may be restricted. We will of course always try to accommodate enthusiastic visitors. We recommend checking a TAO website such as http://www. roanestate.edu/obs before visiting, to confirm that listed events will proceed as planned; weather conditions for example may require a cancellation or change of date. 38 date event details start end Sat 04 Jan 2025 1st Sat Stargaze 7:00 pm 10:00 pm Sat 18 Jan 2025 3rd Sat Stargaze 7:00 pm 10:00 pm Sat 01 Feb 2025 1st Sat Stargaze 7:00 pm 10:00 pm Sat 15 Feb 2025 3rd Sat Stargaze 7:00 pm 10:00 pm Sat 01 Mar 2025 1st Sat Stargaze 7:00 pm 10:00 pm Sat 15 Mar 2025 3rd Sat Stargaze 7:00 pm 10:00 pm Sat 05 Apr 2025 1st Sat Stargaze 8:00 pm 11:00 pm Sat 19 Apr 2025 3rd Sat Stargaze 8:00 pm 11:00 pm Sat 03 May 2025 1st Sat Stargaze 8:00 pm 11:00 pm Sat 17 May 2025 3rd Sat Stargaze 8:00 pm 11:00 pm Sat 07 Jun 2025 1st Sat Stargaze 8:00 pm 11:00 pm Sat 21 Jun 2025 3rd Sat Stargaze 8:00 pm 11:00 pm TAOCalendar Public Stargaze Jan-Jun 2025 These 2025 TAO Public Stargaze events are scheduled for fixed calendar days during the weekend, which will hopefully prove convenient for many visitors with families, especially those bringing younger astronomers. Cancellations often take place in Winter and Spring, due to cold or icy conditions, or overcast and rainy skies. www.roanestate.edu/obs www.ORIONinc.org v. 07 Jun 2025 cancelled cancelled cancelled cancelled cancelled cancelled cancelled cancelled cancelled date event details start end Sat 05 Jul 2025 1st Sat Stargaze 8:30 pm 11:30 pm Sat 19 Jul 2025 3rd Sat Stargaze 8:30 pm 11:30 pm Sat 02 Aug 2025 1st Sat Stargaze 8:30 pm 11:30 pm Sat 16 Aug 2025 3rd Sat Stargaze 8:30 pm 11:30 pm Sun 07 Sep 2025 “1st Sat” Stargaze 8:00 pm 11:00 pm Sat 20 Sep 2025 3rd Sat Stargaze 8:00 pm 11:00 pm Sat 04 Oct 2025 1st Sat Stargaze 7:30 pm 10:00 pm Sat 18 Oct 2025 3rd Sat Stargaze 7:30 pm 10:00 pm Mon 03 Nov 2025 “1st Sat” Stargaze 7:00 pm 10:00 pm Sat 15 Nov 2025 3rd Sat Stargaze 7:00 pm 10:00 pm Sat 06 Dec 2025 1st Sat Stargaze 6:30 pm 10:00 pm Sat 20 Dec 2025 3rd Sat Stargaze 6:30 pm 10:00 pm These 2025 TAO Public Stargaze events are scheduled for fixed calendar days during the weekend, which will hopefully prove convenient for many visitors with families, especially those bringing younger astronomers. Cancellations often take place in Winter, due to cold or icy conditions, or overcast and rainy skies. www.roanestate.edu/obs www.ORIONinc.org v. 24 Jun 2025 TAOCalendar Public Stargaze Jul-Dec 2025 cancelled cancelled moved moved www.roanestate.edu/obs www.ORIONinc.org date event details start end Sat 01 Nov 2025 1st Sat Public Stargaze 7:00 pm 10:00 pm Sun 02 Nov 2025 End of DST 2025 1:00 am Wed 05 Nov 2025 Full Moon 08:19 am Eastern Sat 15 Nov 2025 3rd Sat Public Stargaze 7:00 pm 10:00 pm Thu 20 Nov 2025 New Moon 01:47 am Eastern TAOCalendar Special Events (all times Eastern) Nov 2025 48 To prepare for this multiple occultation I assembled the usual star charts (wide-field and telescope/camera field of view), JPL orbit diagrams, and asteroid shadow path maps, and on 20 Nov sent this material to “ORION and friends” astronomers who I thought might be interested. I had also mentioned this upcoming occultation at the monthly ORION meeting, on Wed 19 Nov. Of course the main uncertainty, as usual, was the weather. In my 20 Nov group email I included the warning that ``weather.com says partly cloudy. but it's downhill from there. CSC says clear 11-12 [pm], but 80% ocast 12-1 am. astrosph says 35% ocast 11-12 [pm], and 93% ocast 12-1 [am]. ugh. But will it change tomorrow? The predicted clouds have lots of gaps. ‘’ The weather uncertainty was very frustrating. As the days and nights passed there was no clear consensus between weather dot com, CSC and Astrospheric about the night of 22-23 Nov. The latter of the three, to which many people tend to assign a higher level of respect, predicted a generally clear night for 22-23 Nov, but with a persistent but fluctuating few hours’ knot of clouds around a crucial period of midnight to 4 pm. I began losing sleep to check the changing forecast every few hours. For a day or two beforehand the postmidnight 23 Nov knot of clouds appeared to be dispersing, but on the morning of 22 Nov it was back with renewed force, so I finally told people that I was giving up on this event, and was going to have a nap. When I again checked online about 4 pm on the afternoon of 22 Nov there was still some interest, and Richard Piety was planning to attend. I however was just too stressed out by the fluctuating weather predictions and exhausted by my lack of sleep, so I said that I might well attend that evening, but without equipment. Richard was the only person to actually set up at TAO for the occultation, and I tried to assist by interacting with him that evening by cell phone and messages, and gave him some information he would need about the two occultations. (There were actually three, there was an earlier faint occultation about 11 pm on 22 Nov, but that one was knocked out by a badly timed cloud.) By then Astrospheric was claiming only a few percent cloud cover at TAO! Richard said there was clearly more cloud than that, but he was still able to set up for the two major occultations of ca. midnight:30 on Sun 23 Nov. Since he was the only person actually present at TAO that evening, I will now turn the narrative over to him. Two Occultations in One Night (cont.) 49 Richard Piety’s section: I arrived at the Tamke-Allan Observatory around 9:30 PM. There was a ring of clouds around the horizon but clear overhead. I decided to take a chance and set up my Celestron C8 with Hyperstar v4 telescope and QHY174MGPS camera riding on a ZWO AM5 Mount. It was a somewhat chilly night at 45-50 degrees F and a light intermittent breeze. I was a little apprehensive about catching two occultation 5 minutes and 144 degrees apart. As I was setting up my equipment and getting the software running. I got a message from Dr. Ted Barnes, “Hey there is a third occultation around 11 PM you might want to catch!” Well, why not? I had a few hours to wait before the main double event. Ted sent me the specifics. Asteroid 97015 occulting star UCAC4 627-018517 turns out to be a magnitude 13.3 event lasting a mere 0.4 second max. This meant I really needed to make 50 mSec exposures to have several data points during the occultation. When I tested my set-up on the target star, 150 mSec with a gain of 450 was the best I could do and still see the star. Even at that setting, the star would occasionally fade away, likely due to a thin haze deteriorating the seeing. However, the image was holding pretty steady as the time to kick-off the capture approached. I was getting optimistic. Its time! Start capture! The star fades away for the entire 60 second acquisition. Expletive! Expletive! Oh well, my primary targets were an hour and 20 minutes away, and they were mag 7.9. I would be able to get them, haze or not. I began my prep for the two upcoming occultations. Asteroid 1234 Elyna occulting star TYC 600-1446-1 at 12:27 am and asteroid 1695 Walbeck occulting star SAO 114492 at 12:32 am. These occultations had a duration of 8.1 sec and 2.0 sec respectively. This would have been great at any exposure approaching 200 mSec. Except that in the dark I read 8.1 to be 0.1! What the heck! At 0.1 sec I would need a 20 mSec or less exposure to get several data points. I tested 20 mSec at a 350 gain and had good visibility. Great! Except to get 50 frames per second (FPS) I needed to decrease the image size to 640x480. Okay, that’s done, I have the star’s position confirmed with a plate-solve in SharpCap, So I will move on to the next occultation and get my setup parameters confirmed for it. Two Occultations in One Night (cont.) 50 For the next occultation, 1695 Walbeck, the scope would have to swing from an azimuth of 118 degrees to a new position at 261 degrees. Once there I would need to plate-solve to center the correct target star, check my focus, change to a more sedate 100 mSec exposure for the 2.0 sec occultation, and prepare to start a new SharpCap video capture. Hopefully with no unexpected mishaps, I would do this in approximately 3 minutes and 20 seconds. It is time! Start the capture! 00:26:48 Start 1234 video capture 00:28:48 End 1234 capture Reposition scope, Plate-Solve, Adjust SharpCap settings, Check Focus, Set up Capture and start capture. 00:32:00 Start 1695 video capture 00:34:00 End 1695 capture. Whew! Success! Pack up and head home. Not too bad, 4 hours invested for 4 minutes worth of data. Two Occultations in One Night (cont.) 1234 Elyna occultation. 1695 Walbeck occultation. 51 Ted Barnes’s section: First we consider the occultation data for the second asteroid, 1695 Walbeck, with the light curve shown on the bottom right of the previous page, since this proved to be an essentially classic occultation with few complications. Richard captured this data with a moderate camera gain of 350 and rather conservative 100 ms frames (this bright target star could have supported much shorter frames; 20 ms would have been my choice). He ran this data through the IOTA analysis programs Pymovie and Pyote; the latter fits a square-well model to the occultation event. The results (with 1s errors) were an event midpoint of 05:32:51.1995(21) UT and a duration of 1.7347(42) [sec]; note the truly excellent tiny errors of 2 ms and 4 ms respectively. As the predicted event midpoint had been 05:32:52 UT with an estimated error of 0.3 secs, this observation is an improvement over the prediction by 2 to 3 orders of magnitude. Similarly there was a maximum duration prediction of 2.0 [secs], so the observed duration is consistent, but much more precise. Inspection of the occultation light curves shows nearly ideal transitions, with a single data point in the Reappearance phase, but two points during the Disappearance. This is evidence that the initial transition was somewhat longer than the frame length of 100 ms. Since TAO was 12 [km] from the shadow center line and the asteroid had an estimated shadow width of 30 [km], the fractional distance of TAO from the center to the shadow’s edge was x = 12/15 = 0.8. If we assume a circular shadow, the predicted maximum duration of 2.0 [sec] would be reduced by sqrt(1-x^2) to 1.2 [sec]. The observed duration was somewhat larger than this rough estimate, but of course an asteroid of this size may be quite irregular. The expected magnitude drop was 16.7 (ast) – 7.9 (star) = 8.8 [mag], whereas the observed drop was 6.5 +/- 0.6 [mag]. This is about as expected; the 3s discrepancy is likely not a problem, since the faint luminosity recorded at the bottom of the well was only about 2s from zero. Finally, note that Richard was the only observer of this occultation by 1695 Walbeck. But for his effort, none of these results would have been recorded and reported to IOTA. Two Occultations in One Night (cont.) 52 Two Occultations in One Night (cont.) Next we proceed to the occultation data for the first asteroid, 1234 Elyna, shown enlarged below as a reminder. This is a very interesting event, with an unexpected and exciting complication. For this event Richard again used a moderate camera gain of 350, but as he stated earlier he had accidentally used much shorter frames of 20 ms. This was quite fortunate, since it gives us much better time resolution for the event, and would actually have been my choice. Richard again processed his data using the IOTA analysis programs Pymovie and Pyote, and the results of Pyote’s square-well fit are shown below. (The target star luminosity measurements are blue; the purple points are from a slightly fainter comparison star.) We can immediately see that the Pyote square-well model does not give a satisfactory description of this data; the assumed instantaneous disappearance (D) and reappearance (R) events are observably distributed over time. From the 20 ms blue points we can estimate that the disappearance took ~ 0.5 sec, and the reappearance was somewhat longer. 53 This data suggests that the light from the target star is a distributed source rather than a point. One might attribute this to an atmospheric scattering effect, or perhaps to the finite size of the target star’s disc. Since the star is of known type and distance, we can first estimate how large its disc should be. Since this asteroid was moving across the sky at an angular rate of 2.14 [mas/sec] (milliarcseconds per second), a disappearance time of about 0.5 [sec] could be explained by a light source about 1 [mas] in extent. The Gaia data on the target star TYC 600-1446-1, a.k.a. SAO 91710 and Gaia EDR3 2766314085176077056, places it at a distance of 547(9) pc, with a g-mag of 7.90 and (from Simbad) a visual magnitude of 8.71, hence an absolute magnitude of +0.02, about 84 times the Sun’s luminosity. Simbad gives a spectral type of M0, and in a HertzsprungRussell diagram these properties classify it as an M0III red giant (see following page). A typical diameter for a red giant of this type is 0.5 AU. At a distance of 0.55 kpc such a star would have an angular extent of 0.9 mas, which is essentially the angular size estimated above as corresponding to a disappearance time of 0.5 secs. Thus the “rounded” D and R light curves seen in the 1234 Elyna data on the previous page appear to be an expected consequence of the target star being an M0III red giant star at 0.5 kpc. Let’s proceed to develop a simple quantitative model of this red giant finite size effect for comparison with the Elyna data. First we assume a uniformly bright circular disc for the star. If during disappearance the asteroid has covered a fraction (x+1)/2 of this disc (x = -1 is contact, 0 is center, +1 is complete), the target star’s brightness will be reduced by a multiplicative factor of fD(x) = 1/2 - (1/p) [ x sqrt{1-x2} + atan(x/sqrt{1-x2}) ] . A graph of this uniform disk disappearance function is shown on the second page following. Similarly, during a reappearance the target star’s luminosity is multiplied by a factor of fR(x), which has a change of sign after the 1/2. To fit the 1234 Elyna data we first subtract the mean value of the luminosity in the well (which the Pyote log gives as 3894) from the data, and then scale it by the Pyote fitted mean luminosity range, 222037 – 3894. This gives target star luminosity data scaled to the mean maximum outside the well, and the mean minimum inside the well, which are then respectively 1 and 0. Two Occultations in One Night (cont.) 54 Two Occultations in One Night (cont.) Position of the Elyna target star TYC 600-1446-1 in a Hertzsprung-Russell diagram. +1.63 0.02 55 Two Occultations in One Night (cont.) fD(x) x = z/R Uniform stellar disc disappearance function fD(x) = 1 - fR(x) = 1/2 - (1/p) [ x sqrt{1-x2} + atan(x/sqrt{1-x2})] . 0 z +R -R Red giant disc and asteroid horizon (z) configuration. 56 For the time axis we assume the mean frame duration found by Pyote, 0.0224365 [sec], and by definition set the time of the midpoint of the initial frame to 0.0 [sec]. According to the Pyote log the initial frame starts at 05:26:47.9857025 UT, so our working data time of 0.0 [sec] starts at that initial UT time plus 0.0224365/2.0 secs. (The latter shift moves us to the midpoint of the first frame, for working time 0.0 [sec].) We fit the disappearance D and reappearance R regions of the 1234 Elyna data separately. Each curve has 2 parameters, the transition midpoint time tc and the transition duration tdur. Note tc and tdur only refer to the D and R events, not to the full occultation. A least-squares fit to the Elyna disappearance data gives the D parameters tc = 56.690 [sec] and tdur = 0.494 [sec] (blue curve). A similar fit to the Elyna reappearance data gives the R parameters tc = 60.609 [sec] and tdur = 0.786 [sec] (red curve). The combined fitted curve and the scaled data are shown below. This model gives a satisfactory representation of the data for our purposes. Two Occultations in One Night (cont.) Least squares fit of the 1234 Elyna data to the uniform-disc red giant star model. 57 These fitted parameter values give a brightness midpoint-to-midpoint duration for the full occultation of Event duration = 3.918 [sec] and an occultation time midpoint of 58.650 [sec]. The occultation time midpoint in UT can be determined as described two paragraphs previously, and is Event midpoint = 05:27:46.647 (UT) . This is about 1.3 [sec] before the predicted time of 05:27:48 (UT), which had a 1 [sec] estimated error. Regarding the duration of the occultation, the predicted duration was 8.1 [sec]. Here the distance from shadow midline was 15 [km] and the shadow half-width was 23 [km], so the suppression of the occultation duration in the circular profile approximation would be sqrt(1-(15/23)^2) = 0.76, giving an estimated duration of 6.1 [sec]. The observed duration of the occultation, about 3.9 [sec], is well below that simple estimate. Of course the size of the red giant that is required to explain the observed light curve is especially interesting, but unfortunately without additional information we can only provide limits. Although we know the durations of stellar “starset” and “starrise” from fitting the target star light curves, and they are respectively 0.494 [sec] and 0.786 [sec], we will see that we also need to know the angle the star makes with the asteroid’s limb on encounter (disappearance) and departure (reappearance). First consider the disappearance. We will initially assume that the star crosses the asteroid’s limb “normally” (meaning at a right angle to the horizon). In this case the setting time for the star’s disc, from contact to vanishing point, is given by Tset = Qstar / wast where the angle Qstar subtended by the star’s disc (in the extremely well justified smallangle approximation) is the star’s diameter divided by the distance to the star, Qstar = Diamstar / diststar . So, we find for our target star diameter estimate Diamstar = Tset wast diststar . Two Occultations in One Night (cont.) 64 References and credits to materials used to produce this article are as follows: The two skymaps showing the locations of two occultation events were generated using the program TheSkyX. The diagram showing angular velocities on the final page was produced using data generated by the program TheSkyX. The Hertzsprung-Russell diagram is licensed under a Creative Commons AttributionShareAlike 2.5 License, as specified at the link www dot atlasoftheuniverse dot com / copyright dot html. The diagram was modified by the addition of a reference to the star TYC 600-1446-1 occulted by asteroid 1234 Elyna. Two Occultations in One Night (cont.) Public Stargaze of Sat 06 Dec 2025 - Ted Barnes These seems to have been some confusion related at TAO access times for this event. Some people such as Richard and to a lesser extent myself needed earlier access than the initially suggested 7:00 pm, in my case because I had been requested by David to start my Moon Music collection with the arrival of the nearly full moon. According to my references the Moon would reach the horizon at 7:10 pm, so I preferred to arrive earlier, perhaps 6:30 or 6:45 pm, to begin setup of my audio equipment. Sunset 5:25 pm Civ dusk 5:54 pm Ast dusk 6:57 pm Moonrise 7:10 pm Moonset* 10:35 am *07 Dec Sat 06 Dec 2025 Waning Gibbous Moon. Bright Moon during this event. Moon illum. 96% equipment. I missed the details of the discussion, and arrived happily about 6:30 pm just as David was opening the TAO gate. I drove down to the NE pad where Richard Piety was already setting up, and set up my lighter complement of equipment for the evening, this Moon Music being played (from 7:10 pm) to encourage the moon to rise above the trees. 7:47 pm Eastern, 06 Dec 2025. Moon position Alt 05.15o, Azi 61.02o. Phase 93.6o. Orion is visible at lower right. consisting mostly of lightweight audio equipment. I briefly strolled into the TAO building, where a visitor had several questions for me about relativity theory. (Several of our visitors were home schoolers, who take astronomy quite seriously. Later another asked me about Polaris not being the pole star in the future.) The earlier discussions were intricate enough that I had to be reminded that I needed to start up the Moon Music at 7:10 pm. Just before Moonrise I remembered that I planned to test the darkness of the TAO skies with my new SQM meter. The result was 20.33 [mag/asec2] in the darkest direction (West of the zenith), ranging down to 20.2 [mag/asec2] (East of the zenith, towards Kingston). The darker value is close to 20.3 [mag/asec2], which corresponds to Bortle 5.0. Lest one be discouraged, I should note that this was at about 7:00 pm, just at the start of astronomical dusk. But for Moonrise, the sky would presumably have grown considerably darker. This will be tested in future TAO visits. Rob (L) giving our visitors a view of the Moon near the horizon with the Meade LX-200. 7:55 pm Eastern. Public Stargaze of Sat 06 Dec 2025 (cont.) Public Stargaze of Sat 06 Dec 2025 (cont.) After some discussions outside and telescope viewing using the Meade, we assembled for astronomy lectures inside the TAO building about 8:00 pm. David Fields welcomed our guests (perhaps about 15 in total) and gave an overview of TAO and associated activities, which took about 50 mins. I had trimmed and updated my asteroids and occultations talk considerably: This Big Kitty-40 version included a basic Asteroids 101 introduction, followed by a description of the 23 Nov double occultation, our most recent TAO occultation. Total talk time about 30 mins. I told the audience about our exciting discovery that the target star for the 1234 Elyna occultation, TYC 600-1446-1, was a red giant. This meant that we could see the dimming and brightening of the target star as the asteroid gradually covered and uncovered the stellar disc. I also noted that the audience, if interested, could read more about this occultation in the Dec 2025 Trapezium (pp.45-64). The warm audience for our TAO astronomy lectures. 8:20 pm Eastern. Public Stargaze of Sat 06 Dec 2025 (fin.) After the lectures ended about 8:30 pm most of our visitors returned to the outside, where the very bright Moon, with Jupiter dangling beneath like a jewel, almost gave the impression of twilight. Popular topics for both the Meade (operated by Rob) and the 8” refractor (operated by Paige and Aaron) were Jupiter and the Pleiades, and since we had a representation by home schoolers, many kiddies as well as adults were present to enjoy seeing these objects. Gradually our visitors thinned, and then departed by about 10 pm. A last puzzle was a very bright object on the horizon to the West. Here my binoculars solved the mystery, and I announced to Richard Piety that it was a star. He was VERY skeptical, but I was right, it was a star, a giant white Christmas star several miles away, composed of artificial white lights. The sky gradually clouded somewhat, and displayed several Moon-backlit faint diffuse contrails. After some discussions with others in the TAO building about what a pleasant night this had been, I finally departed about 11 pm. Wet surfaces had been a problem all evening (we had been near or at the dew point throughout), and while packing up just before 11 pm I noticed that the surface of my worktable had a thin layer of ice. Something to remember and plan for in the coming days and weeks of winter observing! A bright “star” on the horizon to the West. 10:35 pm Eastern. 69 The evening Sky Map for December 2025 from skymaps.com. Note: a nice interactive sky chart from Sky and Telescope may be found at the link https://skyandtelescope.org/interactive-sky-chart/ 70 The evening Sky Map for December 2025 from skymaps.com. 71 Astrophotography Evening of Nov 6th at TAO Meade 12” SCT (LX-200) Canon t3 at prime focus: ISO 100, 1/160 s Edited with Affinity Lunar Maria - Noah Frere IC 5076 – taken from TAO November 3 Due to travel, I haven’t done much astrophotography the last few weeks. The following image of the reflection nebula IC 5076 was made on November 3 using my Celestron Edge HD, ZWO AM5 mount, Hyperstar attachment, ZWO 533 MC pro camera, Williams optics guide scope, ZWO 220MM guide camera, all controlled by my ZWO ASIAIR. Around 17 30second images were stacked and processed with PixInsight. IC 5076 is in the constellation Cygnus near the bright star Deneb. The stars surrounding it are part of NGC 6991, an open cluster. Reflection Nebula IC 5076 in Cygnus - Don Spong Poetica Contributed by Agatha Bardoel What is the late November doing With the disturbance of the spring And creatures of the summer heat, And snowdrops writhing under feet And hollyhocks that aim too high Red into grey and tumble down Late roses filled with early snow? Thunder rolled by the rolling stars Simulates triumphal cars Deployed in constellated wars Scorpion fights against the Sun Until the Sun and Moon go down Comets weep and Leonids fly Hunt the heavens and the plains Whirled in a vortex that shall bring The world to that destructive fire Which burns before the ice-cap reigns. T.S. Eliot from East Coker in “Four Quartets,” (1940) ORION and TAO (and Obed) General Information (links) May be found at the following URLs: https://en.wikipedia.org/wiki/Tamke-Allan_Observatory http://www.orioninc.org/ https://orionastronomy.wordpress.com https://www.facebook.com/ORIONAstronomyTN/ https://www.facebook.com/groups/454645124557215 https://www.facebook.com/pages/Tamke-Allan%20Observatory/120477734665841 https://www.roanestate.edu/?349-Tamke-Allan-Observatory https://www.roanestate.edu/pages/obs/index.htm https://twitter.com/TAOremote [email protected] Where is TAO? (Bortle 5.0) 334 Caney Creek Rd, Rockwood, TN 37854 Gdome = N 35° 49' 56.6”, W 84° 37' 03.8”; Alt. 322 m NE Pad = N 35° 49' 57.4”, W 84° 37' 03.1”; Alt. 322 m Tspot = N 35° 49' 56.7”, W 84° 37' 04.3”; Alt. 324 m Where is Obed? (Bortle 4) Lilly Bluff Overlook N 36° 06' 09”, W 84° 43' 17”; Alt. 402 m Nemo Bridge (on the bridge, E bank of Emory River) N 36° 04' 07”, W 84° 39' 43”; Alt. 268 m Where is LRO? (Bortle 5.3) 182 Burley Nelson Ln, Clinton, TN 37716 36.05779, -84.16799; Alt. 319 m N 36° 03' 28.2”, W 84° 10' 04.8” 81 82 Vol. 49, Issue 4; Fri 15 Apr 2023: Vol. 49, Issue 5; Fri 12 May 2023: Vol. 49, Issue 6; Fri 16 Jun 2023: Vol. 49, Issue 7; Fri 14 Jul 2023: Vol. 49, Issue 8; Fri 18 Aug 2023: Vol. 49, Issue 9; Fri 15 Sep 2023: Vol. 49, Issue 10; Fri 13 Oct 2023: Vol. 49, Issue 11; Fri 17 Nov 2023: Vol. 49, Issue 12; Fri 15 Dec 2023: Vol. 50, Issue 01; Fri 12 Jan 2024: Vol. 50, Issue 02; Fri 16 Feb 2024: Vol. 50, Issue 03; Fri 15 Mar 2024: Vol. 50, Issue 04; Fri 12 Apr 2024: Vol. 50, Issue 05; Fri 10 May 2024: Vol. 50, Issue 06; Fri 14 Jun 2024: Vol. 50, Issue 07, Fri 12 Jul 2024: Vol. 50, Issue 08, Fri 16 Aug 2024: Vol. 50, Issue 09, Fri 13 Sep 2024: Vol. 50, Issue 10, Fri 11 Oct 2024: Vol. 50, Issue 11, Fri 15 Nov 2024: Vol. 50, Issue 12, Fri 13 Dec 2024: Vol. 51, Issue 01, Fri 10 Jan 2025: Vol. 51, Issue 02, Fri 14 Feb 2025: Vol. 51, Issue 03, Fri 14 Mar 2025: Vol. 51, Issue 04, Fri 11 Apr 2025: Vol. 51, Issue 05, Fri 16 May 2025: Vol. 51, Issue 06, Fri 13 Jun 2025: Vol. 51, Issue 07, Fri 11 Jul 2025: zenodo.org/records/8219253 8216818 8030659 8140396 8251302 8336647 8433081 10138151 10382618 10483283 10672625 10822600 10967036 11176951 11646971 12735071 13333599 13742825 13921735 14171218 14394899 14630165 14873015 15015954 15200349 15443035 15660329 15865574 Trapezium back issues online, at CERN’s zenodo database: A full CERN zenodo doi url is for example https://doi.org/10.5281/zenodo.8219253; a short form, e.g. zenodo.org/records/8219253, may also be used. 83 Vol. 51, Issue 8; Fri 15 Aug 2025: Vol. 51, Issue 9; Fri 12 Sep 2025: Vol. 51, Issue 10; Fri 10 Oct 2025: Vol. 51, Issue 11; Fri 14 Nov 2025: Vol. 51, Issue 12; Fri 12 Dec 2025: zenodo.org/records/16884202 17108361 17316280 17615148 17873056 Trapezium back issues online, at CERN’s zenodo database: A full CERN zenodo doi url is for example https://doi.org/10.5281/zenodo.8219253 A short form, e.g. zenodo.org/records/8219253 may also be used. A generic link that lists Trapezium pdf issues (and other ORION documents) starting with the most recent, which does not require a specific zenodo document number, follows: https://zenodo.org/communities/rigel/records?q=&l=list&p=1&s=10&sort=newest Fin du journal December 2025 Link: https://www.visitkc.com/articles/kansas-city-plaza-lights/