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telescopes

Odd Lots

Odd Lots

Ready for the Eclipse

Solar Projection Setup 500 Wide.jpg

I put the 8″ scope together on the driveway to make sure nothing was amiss (and to be sure I could find all the parts) before packing the whole thing off to the parking lot of St. Raphael’s Episcopal Church. Observing the eclipse where I live is impossible, because I’m on the eastern slopes of Cheyenne Mountain, which rises almost 30 degrees above the western horizon. Today’s eclipse will occur while the Sun is setting here in Colorado Springs. In fact, even with a perfect western horizon, the Sun will set before the eclipse is fully past.

The church is almost seven miles east of us, and while there will still be mountains on the horizon, they will obstruct nowhere near as much of the sky as they do from my driveway. It also becomes an opportunity to have parishioners who may be interested come out and see what of the eclipse can be seen from here. The full annular eclipse will be visible from Albuquerque, about 250 miles south of us. We’d considered heading down for it, but there’s just too going on in our lives right now to spare the time.

The projection screen is simple Hobby Lobby foamcore attached to a length of aluminum angle stock with a 1/4-20 threaded hole at its center. I had to crank up my tripod almost to its vertical limit to get it to catch the image of the noonday Sun. The eclipse here doesn’t begin until 6:27 PM, when the Sun will be a great deal lower in the sky. Maximum coverage is about 7:30. The Sun sets here at 8:09.

Of course, all of this assumes that it will be clear later this afternoon. There are a lot of big puffy cumulus clouds up there now, and we had a thuderstorm here yesterday evening. So far so good. I’ll let you know how it goes tomorrow.

Odd Lots

Odd Lots

  • Printed book sales fall, and ebook sales rise by 115%. Something’s Going On Here.
  • I bought an iPod Touch from Jim Strickland and am currently figgering it out. Although I was surprised that it won’t display .mov videos, this article makes much clear about Apple’s video formats.
  • Michael Covington’s 2008 tutorial on reading email headers to spot phish and phakes is worth reading again.
  • Richard McConachy sent me a link to The Great Wetherell Refractor, a hand-made 200mm F9 with some of the guldurndest metalwork in it.
  • There was a horned gopher during the Pleistocene. Really. It is the only horned rodent known, and the smallest horned mammal.
  • From Henry Law comes a reminder of an xkcd item from a while back. For heavenly performance, ground your receiver in a jar of holy water!
  • And that led to this one, which (Ben Franklin groupie that I am) has always been one of my favorites.
  • I haven’t had a monster zin in some time, but last night I opened the bottle of Klinker Brick 2007 Old Vine Zinfandel that’s been sitting on the rack for almost two years. About $18 if I recall. At 15.8% alcohol, it’s among the strongest reds you’re likely to find that aren’t port. Dry but not bitter, with strong spice and enough fruit to balance the buzz. I had about 100ml. Puh-lenty!
  • A cool hack and great visual humor. I have a couple of these little KingMax USB sticks (courtesy Eric Bowersox) and although it would be a bad use of my time, I’m sorely tempted.
  • Accidental visual feast: Search for “steampunk jewelry” on Google Images. My favorite would be this one, which I would title “Time Flies.”
  • In addition to bathroom heaters like the one I bought the other day, the Fitzgerald Manufacturing Company was well-known for making vibrators, (PDF) albeit not the kind that generated plate voltage for car radios! (Could this have been the original killer app for mains electricity?) Thanks to Jim Strickland for the link.

Odd Lots

  • Our good president is creating czars right and left, to the point where you can’t tell the czars without a program. So maybe we need a czar czar–I know a guy named Binks who could do the job…
  • Jim Strickland sent me a decent video demonstration of superfluidity in liquid helium. Liquid helium had a starring role in my 1980 story “Cold Hands,” and Richard Bartrop’s cover image of my upcoming story collection Cold Hands and Other Stories includes Richard’s visualization of liquid helium floating free in atmosphere at zero-G. I don’t think we’ve ever fussed with liquid helium in orbit, but if we have, I’d like pointers to any mentions.
  • In my novel The Cunning Blood, I postulated fluidic computers, which use fluid pressure and flow rates as the encoding units of information. People think I made this up completely, but not so: The technology was in use as early as 1948, and was written up in Popular Mechanics in the 1970s. (That’s where I first heard of it, though I can’t find the citation right now.)
  • If you’re at all interested in the future of the publishing industry and newspapers in particular, be sure to read James Fallows’ take on it. Ad-supported print media are being bled white by eBay and especially Craigslist, which is the direct digital analog of print classified ads.
  • From the Words-That-Sound-Exactly-Like-What-They-Are Department: “Dudelsack” is German for “bagpipe.”
  • Ethanol is a terribly inefficient use of corn (corn stoves that burn it for home heat are a far better use of corn as fuel) and it may destroy engines as well. Thanks to Pete Albrecht for the link.
  • Some years ago, while bumming around my old neighborhood in Chicago, I noticed an observatory dome on an addition to a late 40s house about three blocks from where I grew up. It was right across the street from Olympia Park, where I tried and failed several times to become good at softball. Pete Albrecht noticed that the New York Times did an article on home observatories a couple of years ago, which included some photos of the observatory, built by an accountant named John Spack.

Odd Lots

  • While chasing an interesting “out of the blue” idea that came to me while exercising the other day, I happened upon an RV surplus shop. Not surprisingly, it's in Elkhart, Indiana (Ground Zero for the American RV industry) and it sells leftovers and overstocks of RV parts and interior furniture. If I were to want to built a custom RV dinette table with a built-in keyboard, well, this might be the place to start.
  • Good grief: Has Big Media run out of Republicans to torment? ABC News posted this story about the pastor of Obama's Chicago church, who repeatedly condemns the US in his sermons and tells his people that they should be singing “God Damn America” instead of “God Bless America.” Expect those sermons (which are offered for sale by the church) to become very popular in coming months.
  • Illinois is famous for a lot of things, but being the historical capital of manufacturing of fraternal organization initiation and hazing equipment is not one of them. However, the De Moulin Company of Greenville, Illinois, now known for making band uniforms, used to do a big and almost unimaginably bizarre business manufacturing expensive gag items used to make new Masons and Elks feel like one of the gang. The precise psychology here is obscure to me (the last remotely fraternal organization I joined was the Boy Scouts) but the devices are just insane. Browse and boggle.
  • Here's another source for home-made telescope optics and truss telescope kits up to 32″ in clear aperature. Even though I'm not a big Dobsonian fan, the scopes look good, and if you want light-gathering power above all else something like this is as good as you're going to do short of a full-concrete observatory. The optics are not cheap, but they're good. (Thanks to Pete Albrecht for the link.)
  • Also from Pete comes a link to a site selling Swiss Army Ohmmeters. Should the Swiss Army encounter resistance, well, they'll be ready.
  • Mike Burton (who worked in the industry for some time) wrote to say that “double shot” keyboards are no longer produced due to their expense. A double-shot keyboard is one in which the keycaps are molded in two steps: One step to mold the body of the cap, with a void in the shape of the letter, and a second to fill the void with black plastic. Such keycaps never lose their legends, like my decal-equipped Avant Stellar is now doing at great speed. I guess I had better stock up on period Northgates.
  • We have evidently found the gene that triggers the onset of puberty. One wonders what suppressing this gene would do long-term. What would be the psychology of a 75-year-old boy who had never gone through puberty? Larry Niven toyed with the idea in World Out of Time, speculating that stopping puberty would stop aging, but I intuit that much more could be done with it. Would I give up sex for a shot at becoming immortal? (Answer from this side of the fence: No. Ask me in 1962 and you might have gotten a different answer.) Much depends on whether emotional maturity is a process inherent in or only affected by puberty. Sooner or later some renegade will try this, and we'll know.

Junkbox Telescope Gallery

Some years back I posted Jeff Duntemann's Homebrew Radio Gallery, and for reasons unclear it's become one of the most popular pages on my site. (Tube construction may not be quite dead…) So a while back I wrote up and (almost) finished a page about all the various telescopes I've built out of junk since 1966. Longtime Contra readers have seen some of the photos, but a few are new scans of prints I've had in a box for decades.

Jeff Duntemann's Junkbox Telescope Gallery sat unfinished on a thumb drive for some months, until I finally bore down and finished it a few days ago. It's not a how-to; there has never been and will probably never be a better junkbox telescope how-to than Sam Brown's classic All About Telescopes, which is in turn a compendium of shorter booklets that Brown published through Edmund Scientific in the early-mid 1960s. $14.95 is cheap for a book like this. If you ever have the least inclination to put together a scope from scratch, buy Brown's book first.

The page is mostly a photo collection, with some odd notes on how I did what I did. Note well that you don't have to grind and polish your own mirror as I did. Ready-made 8″ primary mirrors can be had for $300 or sometimes less, and the rest of the scope can be, well, junk. Also note that I think Dobsonian mounts are silly: With a 2″ 45° street elbow you can have something approaching an equatorial mount if you live in the US.

Building scopes like this is mostly a lost art, and there are definitely advantages to scraping up the cash for a Meade or a Celestron. (Tapping in “M31” on a keypad is less messy than lying on your back in a cowfield and sighting the nearly invisible object along the edge of the tube.) But it's a good kid project, because when you're done you—and any involved kids— will know exactly how it works, and that's worth something all by itself.