From the Director

Rex

 

 

 

by Rex Parker, Director

Outcome of Voting Last Month. The Amendment and Expenditure both were approved by membership last month, as reflected in the minutes (in this issue). Thanks to all of you who participated. We’re now operating with a 7-member Board and working on the plan for the new astro video camera, discussed below

Coming Soon! – Game Changer in “Electronic-Assisted Astronomy” (EAA) at AAAP Observatory. Photos below: EAA screen shots showing deep sky objects as they look in real-time in the field without additional processing. See discussion of equipment and software below.




How the Pictures Above Were Made. EAA refers to near-real-time “live” imaging with relatively brief exposures (seconds) displayed on a laptop or PC monitor in the field or observatory. Such images don’t have the same quality as “real CCD imaging” that you see on the web and in magazines which use multiple long exposures (many hours in total) and extensiveand often tedious post-processing. But there’s almost no waiting, it’s happening right in front of you. The club began exploration of EAA a few years ago with the Mallincam color video setup at the Observatory, with great success. Of course, technology changes quickly. The newer CCD cameras are game changers: improved sensitivity, larger CCD sensor size, very fast download rates, small size and weight, and very low power requirements. This allows field use with only a laptop for power supply. Examples include cameras using the Sony EXview HAD CCD sensors such as the Sony ICX825 series. New software, usually camera-specific, is key to the near-real-time display of the RGB color images on the laptop. Software quickly aligns and stacks multiplebrief exposures, so that exact polar alignment is not needed and lightweight portable motor-driven equatorial and tracking alt-az mounts can be used with sucess. Truly a new game.

Recent tests by members have convinced me that this is where AAAP should be. At StarQuest and at the Observatory last fall I tested the Starlight Xpress Ultrastar-color, a CCD camera the size of a 1.25” eyepiece. The screen capture images above show the “real-time” display with no further processing beyond live align/stack/mean of 4 to 10 second exposures by Starlight Live software. The camera was used with these telescopes: (1) AAAP Observatory’s Mewlon-250 (10”), a powerful but “slow” f/12, 3000 mm focal length scope reflector telescope on a Paramount; (2) At StarQuest, with my Tak FS128 (5”), f/8, 1000 mm focal length refractor on a 25 year old Celestron GP mount only roughly polar-aligned.

The Famed Herschel Objects. While folks may have different astronomy observing interests most are keen to see the famous deep sky objects such as the Messier list. But what about the Herschel 400 list? The latter is renowned as an accessible subset of William Herschel’s 1864 General Catalogue of Nebulae and Clusters, the basis of the current New General Catalogue (NGC) as described by guest speaker Michael Lemonick in January. The Herschel 400 objects are all potentially visible at our latitude – they were first found by Herschel in England. My wife and I visited the Herschel house in Bath, England a decade ago. It was fantastic to see the mirrors and a remake of the telescope that William and Caroline Herschel used to discover Uranus and nebulae, on display in the very house where they lived and worked (photos below). The telescope mirror was speculum metal, an alloy of copper and tin. While our skies aren’t nearly as dark as Herschel’s in the 1700-1800’s, our equipment today is definitely better – especially when we bring EAA into the picture! How the Pictures Above Were Made. EAA refers to near-real-time “live” imaging with relatively brief exposures (seconds) displayed on a laptop or PC monitor in the field or observatory.

Board of Trustees Meeting March 26. We’ll hold the next board meeting at Peyton Hall on Monday March 26 at 7:30 pm. Among the agenda items will be a discussion of specific CCD cameras for EAA

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From the Program Chair

By Ira Polans

The March meeting will be held on the 13th at 7:30PM in Peyton Hall on the Princeton University campus.

The talk is by Princeton University Professor Ed Turner regarding the “The Breakthrough Starshot Initiative: A “Funded” Interstellar Flight Project

The Breakthrough Starshot Initiative (BSI) is an ambitious program to send tiny spacecraft to nearby stars within a few decades, traveling at about twenty-percent the speed of light. Starshot will combine advances in micro-electronics, nano-tech and photonics (lasers). These interstellar probes are likely to carry artificial and perhaps sentient intelligences. Will machine based AGIs be better for exploring and occupying the Galaxy than biological intelligences? It may turn out that the stars will belong to synthetic awarenesses – our very different descendants.

Prior to the meeting there will be a meet-the-speaker dinner at 6PM at Winberie’s in Palmer Square. If you’re interested in attending please contact program@princetonastronomy.org no later than Noon on March 13.

We are looking for volunteers to give a 10 minute talk on an astronomy related topic at a future meeting. If you’re interested in giving one please see me at the meeting or contact me at program@princetonastronomy.org.

We look forward to seeing you at the dinner or at the meeting!

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From the Outreach Chair

by Gene Allen

The Outreach Team was invited by a teacher at Stuart Country Day School to introduce star gazing to a class of 4th grade girls plus their parents and siblings. The original date was heavily clouded but the rain date of February 27 started out perfectly clear.

Being only two nights before Full Moon denied us most of the constellations and many of our favorite sights, but we started by showing a bit of lunar detail with the terminator not quite at the southeastern edge. The Pleiades were nicely visible even naked eye, but the nice Mizar-Alcor double was not. Orion was faint but we managed to show The Great Nebula in binoculars and resolve four stars of the Trapezium in a 10” Dobsonian.

An Astronomers Without Borders OneSky, a 5” Newtonian in a tabletop Dobsonian mount, saw First Light and represented itself very well as a $200 starter scope, though it needed a stool to be low enough for the girls.

High clouds encroached to end the program early but the originator declared it a great success.

Ted Frimet, John Giles, David Letcher, and myself participated tonight. Outreach events are entered into the website calendar for everyone to see. Any members who would like to join us for any event or join the Outreach Committee, please write to outreach@princetonastronomy.org.

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February 13, 2018 Meeting Minutes

by Jim Poinsett, Secretary

Minutes of the February 2018 Meeting of the Amateur Astronomers Association of Princeton

  • The meeting was called to order at 7:30.
  • Director Rex explained the amendment to the constitution that was to be voted upon, adding outreach and observatory chairs to the board of directors.
  • Voting was conducted and the result was 46 yes and 0 no. The amendment passed.
  • A second vote was taken on the expenditure of up to $2000 for a new camera and accessories for the observatory. All members present voted yes.
  • There was discussion on the new camera. Three models were possibilities:
    • Atik Infinity
    • Starlight Xpress Ultrastar
    • Mallincam Star Vision
  • There are reviews on all three on the Cloudynights forum. All three will be good for public nights and member use.
  • Observatory –
    • Work continues on the focusing end of the HB refractor. It is anticipated it will be ready for the public season.
    • The observatory duty calendar will be out soon. (It is out now).
    • The columns that hold the roof when it is rolled back continue to degrade. Whether to repair or replace is the main question. Discussion will be continued at the next meeting and the board meeting.
  • Bill Murray discussed training keyholders on what to see in the sky this spring and what will be good to show the public. A date will be picked soon, probably in April.
  • There are several Planetarium/Observatory combination nights planned. The first two on the 11th and 18 of May and the second set on the 12th and 19th of October.
  • The planetarium is planning a special presentation on November 24th called “Choosing Your first Telescope”. They would like several members to show up and set theirs up in the lobby for people to see and ask questions about.
  • John Church announced that the HB equatorial head has been found. It is being refurbished and will be put back in use.
  • There was an outreach event at the Stuart Country Day School on Feb 27th. Check the calendar on our website for more Outreach opportunities.
  • The meeting was adjourned.
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if a tree falls in the forest

and you’re on the wrong side of the park…

by Ted Frimet

An additional observers account of AAAP outreach at the Sacred Heart:

Materials brought to site included:

8” Meade SCT (15 year old scope, alt-az in equatorial mount equivalent install – pointed North, acquired from a Long Island outreach, refurbished, manual only mode. 25mm eyepiece with a passable diagonal).

6” Celestron (Newtownian, German equatorial mount, tripod legs collapsed to accommodate the viewers height, 20mm eyepiece)

15 x 70 Celestron binocular (strap intact for safety, I insist that only a parent or teacher is allowed to put the strap on the student.) small spotting scope – to hand to an observer in the event that binocular or mounted telescopes are not student accessible.

All the above are manual, & all were designated for hands on activity by the kids, or parents. I have done 10 or more outreach (literally just outside our observatory) sessions, last year, using some combination of the above.

Bringing that experience, here at Sacred Heart highlights a few iotas:

When the hands-on scope was set up and ready, almost immediately after announcing its availability, a line grew. This was after the public use of the existing telescopes on the field had already been established, and interest may have waxed and waned.

The “lead” 4th grade astronomer, after being briefed on her Meade 8” SCT telescope, set on teaching others, in line, how to operate in turn.

As the 8” SCT was getting its work-out, I brought out the 15 x 70 Celestron binoculars and handed them off to the first parent, that had none.

I later noted that a fellow astronomer was assisting in acquisition of a star using telrad, on the “hands-on” scope. I breathed a sigh of relief, that the telescope was not unattended, while I was completing a setup, a few feet away.

It is at times like this, that learning functionality trumps true location of a star in a field.

We concur that it is acceptable for a fourth grader to learn how to move a fork mounted or equatorial scope, and not be too concerned with the accuracy of her stellar acquisition.

I continue to observe just how those faces light up, each time they find a star in a telrad center ring, and acquire a star in their eyepiece, of their own accord.

I heard the lead teacher, clearly, when she remarked about one or few stars, and Orion’s nebula. And this must have been concurrent with the various targets, preset by club astronomers, at their scopes.

The “ok to touch and move” display works well enough, when the observer is left to learn, at her own pace. Working independently, she now becomes free of any preconceived notion of what astronomy is. As no adult is choosing for her, I find our budding astronomer forming her own, lasting opinion, experientially.

By the time I had set up the 6” Newtonian reflector, the crowd had diminished. However, I had repossessed the binoculars in time to entertain two parents, and their two girls.

The girls were agape with wonder as they viewed the moon, and the parents had a good view, as well. And further had the opportunity to compare the views from a 6” Newtonian versus the “double” 70mm ocular.

I was surprised when one of the parents discussed the merits of the moons terminator line. And how the moon light interfered with stellar viewing.

A brief engagement in conversation revealed to them that I am from Bucks County.
And one Mom let me know that they were from Newtown, Pennsylvania.

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Hastings Byrne Refractor – Focuser Re-Fitment

by Tom Swords

On one of the last public evenings in October in 2017, I was at the Observatory with Jen and Dave Skitt to observe some double stars after we had closed. Dave and I noted that the focuser on the Hasting Byrne refractor was loose in the optical tube. Upon tightening the screws as best we could, it was still not stable.

Now, I am a long focal length refractor fan and know for certain that a loose fitting focusing assembly cannot provide the stable optical-mechanical alignment that is necessary to set and hold accurate collimation. Collimation in a refractor is simply defined as coaxial alignment of all optical-mechanical assemblies and having co-planar alignment of the objective lens surfaces to the eyepiece. In essence: centered and square.

I mentioned to Dave that I would like to investigate and see about repairing this assembly. I contacted and met with John Church, the curator of the instrument. He showed me a mechanical drawing of the scope and gave me a detailed oral history and recounted work that had been done to it. With that information and some additional investigation, I developed and then presented my plan at the October AAAP board meeting to seek approval to proceed with a repair. Approval was granted and on Nov 20th I began.

To start, I installed a laser collimator and noted where the optical centerline (laser dot) landed on the objective lens. The dot was where my finger tip is placed in the picture below. Think of that spot as the center of field seen at the eyepiece. It is far from the ideal optical-mechanical center.
We also observed that the collimation was not aligned. There should be a single point of light.

The Work Begins
The first step was to check and square the rear of the optical tube assembly (OTA) where the focuser is mounted. Upon correcting that and re-mounting the focuser, installing the laser collimator indicated that we had brought the mechanical centerline to within .75 inches of center. Quite an improvement however, the focuser was still not mechanically stable and centered in the tube.



At my home shop, I disassembled the focuser, cleaned and lubricated the mechanism and replaced the rubber tension washers. The interior of the focuser tube was repainted in flat black. The patina of the focuser was left as is with the exception of the maker’s marks.


Next up was the most challenging part of this project. Properly fitting the focuser to the optical tube.

First, a bit of history is required. In 2002 the original focuser had mechanically failed and was replaced by the current focuser donated to AAAP from BD Instruments. It is a custom made Crayford style device weighing 12.5 lbs, constructed of brass, steel and aluminum. However, upon initial fitting in 2002, it was found that focus could not be reached. The OTA was shortened by 1 inch to achieve focus.

Also notable was that the original focuser mounted on the outside of the tube (i.e., the tube slipped inside the focuser). However, the shank of the replacement focuser mounts inside the tube, with machine screws drawing the tube tight to the shank.

The Hastings Byrne OTA is tapered along its length; its diameter is greater in front (at the lens cell) to less in back (at the focuser). When shortened, one inch of the original round section of the OTA supporting the focuser was removed. The result was that part of the new focuser shank was no longer securely in contact with the tube walls. That is why the focuser would become “loose” over time. This can be thought of as a round cylinder inserted into a cone that opens wider.

The OTA ID was measured to be .120” bigger than the shank of the focuser. In addition there was a soldered “lap seam” inside the tube. Unlike today’s seamless aluminum telescope tubes, telescopes constructed in the 1870’s were made in sections of steel or brass. The seams were then soldered with lead and the sections riveted together to form longer tubes.

So I set about constructing a “shim” of mild steel that would be fitted on the focuser shank in order to make up for the space in the larger section of the tube. It also would require a gap to accommodate the lap seam inside the tube. It was constructed from 16ga mild steel that was rolled and then ground to a custom fit between the shank and the ID of the OTA. The final thickness of the shim was .055” and that provided a .010” clearance fit to the tube.


The OTA itself had burrs and dents that were removed along with some gentle expanding to remove the taper of the tube and provide a closer fit of the focuser shank.


After many hours of grinding, trial fittings and adjustments, the shim and focuser were installed on Feb 14th for final trials. The original 6-32 sized fasteners were used initially. The hose clamp, shown in the photo, holds the shim in alignment on the shank while the whole piece is being inserted into the tube. The optical train was then laser aligned to be within .250” of center and the OTA was re-collimated using a refractor collimation tool.


The First Trial
On Sunday Feb 18th, Jen, Dave, my wife (Karen) and I went to the observatory for the trial run.
We decided to use double stars for testing. Viewing began with a 17MM eyepiece @136X. We started in Orion and all of us immediately noted how considerably brighter the views were. Despite the variable viewing conditions doubles were split very cleanly.

The Trapezium in M42 was perfect and if viewing conditions were better we might have seen the E & F components. We viewed 4 stars in Sigma Ori.
Meissa @4.5” separation was very sharp and defined.

Still in Orion, Jen steered us to HD 33055, a Mag9 double @ 2.4” separation that was split perfectly.

We went to Cancer and checked Iota Cnc and Tegmine. Beautiful.

Last target was Algeiba in Leo. I decided to test at high power to see if we could observe an “airy ring”. A 8mm eyepiece for 289X was used.

We observed two perfect spheres with first diffraction rings on each! The rings would come and go, break and reform as the atmosphere played above us. The trial was a success!

The following week, the focuser was removed and the shank was drilled and tapped for larger
10-32 button head socket screws that provide increased torque for mechanical stability. It was reinstalled on Feb 26th. The mechanical alignment was adjusted to be within .125” of center. The OTA was then re-collimated. The finder scope and grab handle were re-installed. Although there is still some cosmetic finish work to be completed on the tube, the telescope is ready for service.

On Feb 27th, Jen, Dave and I did some observation along with re-calibration of the T Point table in TheSkyX. This was done so as to correct the pointing of the mount since the optical center of the telescope had moved with the improved optical-mechanical alignment. Although sky conditions were less than ideal, observation showed that collimation was correct.


I feel privileged to have worked on this historic instrument and would like to thank the AAAP board and John Church for allowing me to do so. It’s ready to observe more of the Heavens and better than ever for its 200 year anniversary in 2079!

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Ice Cream Has No Bones

Feynman was here.

by Ted Frimet

A pleasant lecture was had by all, at last Tuesday’s meeting in Princeton. Paul Halpern was informative, and entertaining as he discussed his book on Richard Feynman. And then I stepped into the trap I laid for myself. When Dr. Halpern was discussing Feynman’s thoughts on electrons moving forward, and backward in time, (evidently the math works, so I’ve been told) I asked a neophyte question if this was akin to quantum tunneling, with an electron paying the price of time, as it passes thru no space, at all. Our author was quick to point out that this theory of the realm of quantum theory was akin to the 1920’s time frame. After prodding him gently, as one would stir a Gridnard reaction into place, Paul helped me out by reminding all that the motions of this particular electron (or positron – depending on your time movement) was taking place in the 1950’s. Oh, Richard – we could have used a smoke and joke, here!

Time is relative. Questions and answer time, doubly so. And when the time came for Q&A, I too heard crickets. I bounded and twisted from my chair, knowing how the speaker felt, and at once queried you all – as if you had no question of your own to offer? And begged my way into asking of the good professor, “whatever happened to Ms. Bell?” You know the answer we got. And the floor was opened and I rejoiced in hearing and listening to all of you participate.

Feynman finally moved me. You see, I’ve been reading “New Quantum Universe” by Tony Hey, and Patrick Walters (which leaves out the math). You now have a clue as to where I am studying Quantum Physics (circa 1980). And although I had been taught, previously that Richard Feynman was difficult to learn from, I ushered into my living room, in the comfort of my own home, the YouTube channel that hosted his 1979 lecture from New Zealand. Auckland, I recall? And I learned that Richard is the man! Funny, bright, succinct, and yes, easy to understand. Why, I even drew reference from Feynman’s work. I compared it to a recent review I am working on. I am critiquing the graphic art in a 50 minute video discussing the underpinning of Snell’s Law. But you don’t want to hear of that until I finish the graphical critique. Stay tuned, because I’ll give a shout out to the author, here, in Sidereal Times, when the bun is out of the oven.

I am writing this second essay, because I wanted to relay to you what I’ve learned, recently. That Buddhists teach that once the mountains are mountains. And then you realize they aren’t. And then, they resolve to be mountains, once again. Boy, I really butchered that thought. Feynman helped me re-engage our reality of light. That is, when light “hits” matter, it causes the electron quantum state to either excite, or cascade into a lower level (basically). And in doing so, emits a photon of its own. Sometimes two or more. Depends on your physics. This photon, may in its terminus, reach your eyes.

So my mountain, as I explain it to you, may be lit by suns afar. However I never get to see the reflected light. It is in fact, re-radiated by the electrons of that matter, itself. As Amateur Astronomers, you get this immediately, as we turn our attention to White Dwarfs emitting non-visible Ultra Violet energy, being absorbed by a non-visible veil of a Nebula to be re-radiated by a now – visible Nebula. Ah, essays of old come to roost once again. However, when you look at the paint on the walls, it just doesn’t seem that the wall color isn’t reflected. At least, at first, until you grasp at the electrons doing the physics provide you with the privilege of seeing the wall color. Illusion of light prevails. Things are quite what they seem. And we rely on our brains to fill in the missing pieces, and help us maintain our sanity, less we stop to ponder the true nature of matter and energy.

I laughed out loud when Richard Feynman talked about a physicist that might not accept the light coming from their meal, when presented with a real steak on a plate. Poorly paraphrased here, he mused to the audience that those scientists that would refute the light, would end up being very hungry physicists. I suspect they would be selected out of the gene pool, for sure.

I have to stop now, and eat dinner. And do so before the cat photons eat the chicken tenders.

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