Trifinder Trouble

by Ted Frimet

It’s the end of the world as we know it.

A brief recapitulation on the status of my cats endeavor to improve the sighting accuracy of my 12 inch dobsonian telescope by way of collapsing his cat tower onto my behemoth. The cat survived. And the dob has good views. Good news, all around. As for the horizon challenge laid out by a member of another club – I am at the precipice of understanding, by way of an 80 year old scholar, that given the several concentric lines that represent each passing billion year eon, that our shared astronomical sight lines extend from one point in a horizon, to another. As a line is drawn, from the observers point to the observed, as a geometric chord across the curvature of our graph, the area under the curve is my horizon.

Hence, my answer to the esteemed gentlemen of other club grand stature is that I now proclaim “horizon” to be a relative term. Did anyone take a breath? Did you want some dressing with that word salad? Wait for it. One more verbal equivalent of the hand jiggle to get all the wiggly wigglies out!

If you fast forward to the end of this essay, you will find an embedded cat meme, produced by yours truly. I would rather you get the message, other than the fortuitous laugh. The message being, “please spay or neuter your pets”. This message comes to you, across a vast emptiness of space and time, experienced by myself, and my recently adopted feral family of one. This cat, although not personally reared to be a telescope destroyer, has recently chucked up a couple of hairballs in protest of my dobs’ temporary location in her lioness lair. However, to be fair, she is good company, and we have changed her name from “Hissy cat” to “Priss” of the Hunger Games variety. Could not ask for a better companion while hunting down faint fuzzies.

Your world is about to come to an end. And I don’t mean to relay any confidence, that this article dated September 23, 2017 has anything, coincidental to share with the end of world phenomenon espoused by others. They don’t write here, and I don’t credit ‘em being credible. Besides, I am hardly on the cusp of credibility, myself. Here is what I had to say on that: After careful calculations with a rubber band, and a ruler, I have prognosticated that a 28 meter wide asteroid will impinge operability of the ISS composting toilet, creating a causality “Do – Loop”.

No, sincerely – the only astronomical item that might coincide with the end of world event, is Asteroid J2012 TC4. The Apparent Magnitude (as seen from Earth) should be just under 22, for today. It will be closest on October 13th. As it approaches Earth with 0.10 lunar distance, the gravity will accelerate the asteroid, increasing its APMag from 16 to 13. Making it a decent target for amateur level scopes.

Unfortunately for AAAP members, the asteroid will be either below the horizon, at peak magnitude, or below the tree line. The end of the world however will have a vantage point, no matter where you observe from!

Wiggles done. Engines engaged. Warp drive committed. And now…the end of the world: PUT AWAY YOUR TELRAD. Ah got your attention. At this years Starquest we happen
across Dr. Peter Wraight, and his hand developed and simply sublime construction of astronomy grade binocular viewing devices. After being completely blown away by the reflective mirror he employed in one, and the 100mm lenses from another, I am pleased to say that you no longer have to crane your neck to get a good view of the sky thru binoculars. Could this almost be too good to be true? Well, yes. There is a slight bit of craning to be done, however, not what you would expect from Dr. Wraight.

Peter has developed a finder. You decide on a target in the night sky, and pick two guide stars of magnitude 3 or brighter. You then can either calculate, or use his NGC guide book (with pre-calculations) to obtain, a reference angle. He has written program code to doggedly convert right ascension/declination into his new Trifinder system.


As pictured above on our finder disc, two sides of a triangle (not shown), one leg ends at one guide star, the other leg – the other star. And at their vertices you will find your target. Easy Peasee. And if you didn’t get it the first time, the vertice angle is formed by the two legs. On Peter’s finder, one leg is calibrated and can span up to 18 degrees with illuminated dots for each degree, while the other is represented by a small illuminated line pointing toward three illuminated dots and spans 22 degrees. The finder incorporates a simple lens and a semi reflective perspex disc to effectively project an infinity image of this “triangle” on the sky above. Move the dob so the end points are on the guide stars, and Wa-La! – target acquired at the vertice. The seeing is the believing! I’d write more on The Trifinder, however, we should all encourage Dr. Peter Wraight to publish his work, on the web for all to know and tell.

Meme as promised:

This entry was posted in October 2017, Sidereal Times and tagged , , . Bookmark the permalink.

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