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November, 2020:

Odd Lots

  • Wow. The magazine that gave us “The Case for Killing Granny” is now saying that our public health officials have overcounted COVID-19 deaths by counting any person dying with COVID-19 as dying of it–including suicides and, sheesh, car accident victims. This has been known for some time, but I give the otherwise dopey Newsweek credit for admitting that government isn’t always right.
  • More on how we count COVID-19 deaths: Johns Hopkins published a paper suggesting that we are overcounting COVID deaths and undercounting deaths from other causes like heart disease. By misclassifying deaths as from COVID, we undercount deaths from other causes. The authors of the paper suggest that this means COVID-19’s impact on US deaths is far less than commonly stated. Johns Hopkins has predictably deleted the article, but there’s an archived copy on The Wayback Machine. Well worth a read–and possibly worth saving the original Johns Hopkins article to local disk in case threats of legal action force Wayback to take their copy down.
  • A new paper posits that UVB in sunlight stimulates the production of antimicrobial peptides (AMPs) in the skin, especially cathelicidin (LL-37). LL-37 has several roles, but it has been shown to inhibit the action of the influenza virus in humans. AMP action involves Vitamin D, but the D3 found in OTC supplements does not appear to work with it. My serum D3 tested toward the top of the recommended level several months ago, but it’s hard to know how much of that was produced in my skin in this (outrageously) sunny place, and how much came to me in pills.
  • David Prowse, who played Darth Vader in the original Star Wars movies, died yesterday, at 85. He was 6’6″ and was given the choice of playing either Vader or Chewbacca. He chose Vader because “you always remember the bad guy.” (Well, true. But nobody’s going to forget Chewie, either.) Click through to it: The photo of gentle giant Prowse with six little girls in a UK safety program is priceless.
  • Somebody did a test on the startup time required for programs written in various languages, including nearly all of the ones I’m familiar with. (At least those that weren’t Xerox in-house experiments.) FreePascal 3.0.2 and 3.0.4 beat all the others, hands down, not even close. I don’t know enough about compiler internals to tell how one gets that kind of startup performance, but you sure as hell do not get it with C# or Java.
  • I should add that if you’re on Twitter and work in Pascal, you must follow @SciPasTips.
  • Bummer: The Arecibo radio telescope will be scrapped. Stuff is breaking in the basic structure of the mechanism that just can’t be swapped in without rebuilding practically the whole thing. That reflector comprises eighteen acres. It’s been in operation for 57 years. Wait! I have an idea! Let’s build an even bigger one…in space! (Yes, I’m pretty sure Heinlein thought of it first.)
  • As far as I’m concerned, this kid wins the Best Halloween Costume Award not only for 2020, but for the rest of time.

Bringing the 10″ Scope Back to Life

Joe Lill and 10 Inch Newt - 3-8-1970 - Cropped.jpg

When I was 14, I took an opportunity and started out on a very large project: A friend of mine bought an Edmund Scientific mirror-making kit, decided he didn’t have the time to pursue it, and sold it to me. The kit included a 10″ Pyrex mirror blank, a plate glass tool blank, and all the abrasives needed to grind and polish it. I did most of the grinding in my basement, using a defunct round wringer washer as a grinding station. I followed the instructions in the kit, along with whatever I could find in the library, and though it took a couple of months, in time I had a Pyrex blank with a smooth curve, focusing at about 67 inches. My goal was 70, so I came pretty close, and in truth, 67″ would make for a shorter and somewhat lighter tube.

Now, grinding is only half the job. Polishing the ground mirror surface took sophisticated methods to gauge the accuracy of the curve, which has to be a parabola to focus items at infinity (like stars) to a sharp image. I decided I was over my head, and did the sensible thing: I enrolled in a class at the Adler Planetarium on Chicago’s lakefront, which took up most of the summer that I turned 15. They had an optical shop in the basement that included the required Focault tester, plus a superb teacher, Ken Wolf, who helped me get the polishing done and mirror curve accurate. They were also able to aluminize it, and by that fall, I had a 10″ F6.7 parabolic telescope mirror accurate to 1/25 wave, which was bogglingly accurate for a first shot by a 15-year-old.

The rest of the scope took another two years and change to complete. A friend’s father made me a tube out of sheet aluminum. I built a tube saddle out of scrap wood and hardware-store aluminum stock. I had no tools more sophisticated than my dad’s circular saw and saber saw. And that was for woodworking–for metal I did it all with a hacksaw and files. I had some help from my high school machine shop teacher, who dug up a piece of iron that he said was hull metal from a scrapped battleship. He cut it to size on the big bandsaw for me. I spent many study hall hours in his shop on one of the lathes, boring out 2″ pipe fittings and making numerous small parts. I owe Mr. Brinkmann a huge debt of gratitude. Without his help and the use of his machines, I could not have finished the scope.

It was going to be a big scope, and a much heavier one than the 8″ Newtonian I had built from a Sam Brown book the summer I turned 14. I turned my attention to building a base. There was a lot of scrap lumber in the crawlspace. I had the notion of building a cement form out of scrap lumber and pouring a solid triangular concrete shape 36″ on a side with bolts embedded in the top for the battleship-metal mount.

So I built me a cement form.

Whoops. Doing some math and library research showed me that the concrete base would weigh at least 400 pounds. Yes, I could make it–but once I made it, I had no idea how I would move it. So I was left with a scrap lumber cement form…


FirstDateSketchTelescope - 325 Wide.jpgThe form was made entirely from 2″ dimensional lumber, from 2X4s to a scrap of 2X12. I could carry it around with only a little puffing. So I would use the cement form as the telescope base.

A lot more work and allowance money would go into the telescope before I finished it–more or less–in the fall of 1969. On an early date with a pretty 16-year-old girl I had met in church, I told her about the project and drew a picture of it on her little spiral notebook. (See left. She enjoyed talking about science. So did I. She married me in October 1976, and our flag still flies.)

I used that scope a lot, even though it was bulky and heavy and awkward to cart around. In 2000, I (finally!) poured a concrete base for it at our house at the north end of Scottsdale. (See below.) I bought a large plastic trash can to put over the scope to keep the weather off it, and enjoyed it tremendously. Well, we moved to Colorado in 2003. When I went behind the garage to fetch out the now-retired wood base, I discovered that the local termites had been feasting for a couple of years, and there was nothing much left.

I haven’t had the 10″ assembled since. And it’s now about damned time to get to work.

10 inch with Michael Abrash - 2001 - 500 Wide.jpg

I’ve spent a couple of weekends messing with it. Yesterday I bolted the aluminum tang to the base, and although there will be some refinements, what you see below is pretty much what you’ll see when it’s in service.

New 10 inch wood base 1- 500 Wide.jpg

The equatorial head is still workable, though tremendously heavy. I hope to build a new one out of aluminum. In the meantime, I see no reason why I can’t have it up and working by the time of the Great Conjunction of Jupiter and Saturn on December 21. The two giant planets will appear just 6.1 arc-minutes apart, close enough to see in the same eyepiece field, and closer in the sky than they’ve been since 1623. A conjunction of this sort is said by some to be the Christmas Star that the Three Wise men followed to Bethlehem. Miss that? No way!

More on the 10″ scope project as it happens.

I’m Still Here

I’m still here–and still healthy. One of my correspondents asked in an email if I had stopped writing on Contra because I’d caught the virus. I haven’t. Motivation and energy are an issue, with both in somewhat short supply. That said, the truth is that Contra is mostly for long-form essays, and I’ve been stumped for concepts recently. I don’t want to talk about the election. There’s nothing I could say that others haven’t said a zillion times. And the pandemic is depressing enough. Politics would put me into a coma.

There are other issues that I’m sure I could talk about, and I’m pondering one now, which I hope to post in the next few days. And I need to do an Odd Lots. What I need to do most of all, however, is stop waiting for a 3,000-word entry to occur to me. Personal energy might allow me to get the ideas, but it might not allow me to produce the copy.

So what I may do here is go back to short subjects for awhile. I may duplicate entries posted here on MeWe or possibly Facebook. I’m annoyed at Facebook for blocking a link to a news item because Facebook doesn’t like the site. They didn’t say the item itself was false or misleading. They just said that the site wasn’t trustworthy. Well–who’s trusting the New York Times these days? Mostly people who agree with them. Is that the future? All media becoming hyperpartisan and excluding links to sites for strictly ideological reasons? That’s pretty depressing too.

And that’s why I created an account on MeWe. Unlike Facebook, they don’t have enough subscribers to allow them to alienate 49% of their readers with stupid ideological posturing. The list of things they won’t allow is short and sensible: Nudity/porn, threats of violence, impersonating other people, etc. It does not pass judgment on legal content. It doesn’t sell ads or track users. It’s American-owned. Its business model depends, like so many others, on selling premium accounts. Whether that’s enough to keep them afloat over the long haul is debatable. But for now, with millions of disgruntled Facebook users flooding in, its future looks tolerably bright.

This entry is just to reassure you that I haven’t abandoned Contra. I’m going to spend a good part of the afternoon writing and queueing up some shorter entries that I will post in coming days. That’s what I did when I created Contra (and its predecessor, VDM Diary) 22 years ago. So everything old is new again…except maybe bell-bottoms and BASICA.