The needle of a phonograph is more formally known as the stylus. While trying to procure one of them, I've learned that the web-literate audiophile community does not have a very firm grip on this word.

One major vendor of styli seems to think styli is the singular. ("This is a styli for a Pickering V-15...")

Another thinks the plural is stylii, a misspelling that must occur 1000 times on his copious web site.

I don't want to name either of these vendors because I may be about to do business with them - they look like good outfits despite lack of Latinity - but I challenge you to find them with Google and maybe even break the bad news to them.

Incidentally, whenever you see a plural or a genitive (Latin possessive) that ends in -ii, it's because the base form ended in -ius. The first i isn't part of the suffix at all.

And even more incidentally, the word virus has no Latin plural. Not viri and certainly not virii. Its last two letters are not the usual -us suffix; their origin is obscure.

This picture shouldn't have shown anything at all, but here it is. At the top you see the spiral galaxy M51 and its satellite galaxy, to which it is connected. Near the bottom, another fuzzy spot is an 11th-magnitude galaxy.

I took this last night under rather poor conditions - the sky wasn't very dark or clear - using my Digital Rebel and an old 135-mm Pentax lens at f/4. I stacked four 5-minute exposures and subtracted a stack of 3 dark frames. The ability of the digital camera to subtract out skyglow is almost magical.

What happened is that a photographer from the Athens Banner-Herald came over to take a picture of me with my telescope. I had it set up for astrophotography, so after he left I decided to attempt a picture.

I didn't even make guiding corrections, although the PEC was programmed and the drive ran very smoothly.

What you see is the small central portion of a much larger picture. I had the dim idea that Comet Machholz, which is still hanging around in the northern sky, would be in the picture too. Unfortunately, it was just a bit too far away.

No, I'm not talking about Lemony Snicket.

Over the weekend, while making backups, I apparently had some kind of accident, or fell victim to an unrecognized software bug, and deleted my entire collection of astrophotography computer files (logbooks and digital images) without knowing it.

Naturally, this happened just before the backup.

Fortunately, I only lost my work from 2004, and 2004 was a slow year. Most if not all of 2005 was still on my laptop and I just copied it into place again. Up to 2003 I had CD-ROM backups.

From 2004, I still have printed logbook pages including lots of pictures, so I haven't lost any knowledge of which techniques worked and which didn't.

Also, fortunately, the images from this Notebook survive, and almost all of 2004's work was planetary imaging where the images in this Notebook are actually full resolution, rather than downsampled.

The only real loss was the full-resolution version of the lunar eclipse picture that you see here (from October 2004).

All of this was definitely bothersome. From now on I back up twice as often!

I actually saw some mention of Ana on an episode of Law and Order but thought it was fictitious.

Last night the University of Georgia surprised all its computer users by announcing a new policy that requires the following disclaimer on all web pages except official ones:

The content and opinions expressed on this Web page do not necessarily reflect the views of nor are they endorsed by the University of Georgia or the University System of Georgia.

Disclaimers should not be necessary on personal web pages that are clearly recognizable as such. The whole Web community already knows what a personal web page is.

I am pressing for the policy to be amended. Very few people actually create web pages in bad faith - intending for them to be mistaken for official ones - and the rest of us (32,000 students and 5,000 employees or more) shouldn't have to type disclaimers on every web page just because of a few bad eggs.

I spent a good bit of time gadgeteering today. I found a good Sony DVD+-RW drive at the local Wal-Mart last night for $40 after rebate (!), and it's now installed in Minerva, my main desktop.

Meanwhile I used Artemis, Melody's desktop, to capture audio from some old cassette tapes in order to create CDs.

This is something we've done sporadically over the years. It's often amazing how much better the CD sounds once it's been through some intelligent signal processing.

Here's how we do it.

(1) Connect the computer to the stereo. The easiest way to do this is to treat the computer as a tape deck. Tape Play on the stereo goes to Headphone on the sound card, and Tape Record goes to Line In on the sound card. This requires 2 of the cables that come with every sound card (except that only one of them comes with every sound card, and you probably want longer ones anyhow).

(2) Record and process the audio files with GoldWave. This handy shareware package - with a generous free trial period - not only records sound, it also filters it to eliminate pops, crackles, and tape hiss, as well as providing a full range of editing functions, including the ability to chop up one file into many songs automatically by finding the silent intervals between them.

(3) Select a group of the resulting .WAV files, right-click on "Add to Burn List," and let Media Player make them into an audio CD.

Today I was doing something harder - trying to retrieve a couple of record albums of which I only have low-quality monophonic cassette recordings made over 30 years ago. The results did sound better than the original tapes, but you can't spin lead into gold, and I quickly found that the original albums were both available on eBay, so I'll probably buy them and transcribe to CD from vinyl.

A subsequent project will be to get a 78 rpm needle for my Pickering cartridge, then transcribe my father's records, which he bought from a jukebox owner around 1950. We have some interesting items!

I haven't seen the latest Star Wars movie.

One Star Wars movie, in 1977, was very refreshing. A couple more were welcome. But I don't need six.

What's worse, there are indications that, in the latest movie, George Lucas sacrificed plot consistency in order to take a potshot at President Bush or at conservative values in general.

Apparently, if you "think in absolutes" you are not a proper postmodernist liberal. People who make bumper stickers have certainly latched onto the quotation. Click here to Google for "Only a Sith thinks in absolutes" and see what it has led to.

I'm not sure what they mean by "thinks in absolutes." Is Mr. Lucas advocating subjectivism or just subtlety?

Paradoxically, believing in absolute truth is the only reason to be tolerant. If there is objective truth, then there's a chance you're objectively wrong, so you should tolerate those who disagree with you. If there is no objective truth, all debates are just power struggles, and there's no reason not to stomp on anybody who gets in your way.

Hang on to your hats - I have a lot to write about today. Let's begin with my latest evening with a 5-inch telescope (May 18). The pictures below were taken with my vintage Celestron 5 (25 years old this year) and a Philips ToUCam Pro (640×480 pixels). The Jupiter image used a ×3 Barlow lens; the moon images did not. Each was recorded as about 1000 frames of video, then the best 600 to 800 frames were selected, stacked, and enhanced with Registax 3.

Not bad for a telescope the size and shape of a coffee can! The last of these is better than the best film photographs ever taken of Jupiter with telescopes of any size (even the large observatories). In an astronomy textbook of, say, the 1970s, you would not see a picture of Jupiter that good.

In defiance of a United Nations ban, the University of Newcastle has cloned human embryos. They plan to break them up to harvest the stem cells.

Human cloning is here. I'm against it for all the usual reasons. Principally, I'm against breaking up or discarding human embryos. As Dr. Seuss put it, "A person is a person no matter how small."

But there is a second issue we need to raise immediately: full civil rights for people who are conceived by cloning. I'm afraid too many people already have the preconception, based on science fiction, that human clones won't be "real" people, and that it will be OK to enslave them. Balderdash! Let's get on this one immediately.

Our economy is shifting gears, but it's hard to tell what gear it's shifting into, so I've been reading up on economic matters. I should emphasize that I'm not an economist.

Item 1: I'm not the only person who has noticed the dubious practices of the credit card industry. There has been a Senate banking committee hearing, and here's some of the testimony.

The point? Suppose a lender said:

The interest rate on this loan is 6%. But if you are even one day late with a payment, or if you are late with a payment to some other creditor, or anything else happens to lower your credit score, we will either raise your interest rate to 29% or else demand that you pay off the loan immediately.

I'm tracking this issue; you'll hear more about it. We need a national usury law.

But there's a bright side. According to an anonymous Congressman that I saw quoted somewhere, all this competition has put the Mafia out of the moneylending business.

While rooting around for some insights about this, I came across the very useful web site of the Federal Reserve System and learned that they help to publish a scholarly journal (using LaTeX, hurrah!). And in it is this article about monetary policy neglect.

The article's point is that a government should always control the money supply by making interest rates track inflation. (This is how you make your money keep its value.) If you try to keep interest rates too low, you let inflation run wild. And if you pretend that inflation is caused by something other than the money supply - as Australia and New Zealand did for a long time - you lose control of it.

Back during the Great Inflation (1967-79) in the United States, people and even governments seemed to think inflation was caused by:

• Retailers raising prices;
• People wanting too many goods and services;
• The minimum wage being too high; or
• The Arab oil embargo.

(Inflation combined with low interest rates does leave the housing industry better off, because of its dependence on long-term borrowing, and one of our hot political issues around 1978 was whether to run the economy for the benefit of housing or for the benefit of everyone else.)

I grew up in south Georgia, and my mother's family is from southwest Georgia, land of the gopher tortoises. These increasingly rare reptiles have finally made it onto CNN. They are closely related to the desert tortoise of the American West (also rare) and the giant tortoises of the Galapagos Islands.

They really are disappearing. I last saw one in the wild, crossing a road, in about 1987. And now the word is that they are being wiped out by the invasion of armadillos from Texas. I knew those armadillos were up to no good!

The latest obnoxious custom to break out in modern society is the practice of charging your friends money to attend your wedding.

This practice is, as Sharon tells me, "already in etiquette Hell," but some people don't have any sense. The faux pas of a few rich fools can all too easily trickle down to become a fad among the less knowledgeable.

When the concept of marriage goes askew, it can't be long before the wedding also turns into something goofy. For some people, it's apparently nothing but a big party. They've lost all awareness that it's actually something else.

Another factor is the 20th-century custom of pretending, at your wedding, to belong to a considerably higher socioeconomic class than you really do.

Partly, this pretense comes from a praiseworthy ideal - you want to honor your marriage by celebrating it in as dignified a way as possible. That means imitating rich people, who have the best of everything at their disposal and (we hope) can be trusted to do things in style. (Maybe.)

But partly, it just turns into a game of pretending to be rich, and trying to impress people with how much money you can spend.

When Melody and I got married, making people think we were rich was not on our list of goals. Nor was giving them the party of their lifetime.

Our goal was to celebrate Christian marriage. It was 1982, and people were asking us, "Are you going to get married or just live together?" Definitely the former!

This implies that we wanted a church wedding in front of our families and a reasonable number of friends, with a very traditional ceremony.

Melody took the lead in controlling costs, and she did an impressive job. We kept things dignified but simple. It helped a lot that the rehearsal dinner and reception were in a Baptist church hall, with no alcoholic beverages. Anyhow, our families just aren't drinking people.

Nor did we have dancing and a band or DJ. Probably not 1% of the guests knew how to dance. Certainly not Melody or me!

And as you can see, we came out quite successfully married.

Now then... What are we to make of the young upstarts who want to charge their guests money? Or the slightly more established custom of demanding that the guests fly to Hawaii or some other vacation spot for a "destination wedding"?

The goal is obviously not to appear rich. The goal seems to be marketing the wedding as an entertainment package.

Folks, we didn't have our wedding primarily in order to entertain people. We had it in order to get married!

This image of the lunar craters Copernicus and Eratosthenes was captured the same way as my recent pictures of Jupiter, but when I processed the video, I got better results by selecting the one best frame than by trying to stack the best 59 frames. The reason, I think, is that this picture covers a much larger patch of sky than the face of Jupiter, and the whole picture doesn't move in unison when there's atmospheric turbulence.

Note the two ghost craters above center - the remains of ancient craters, visible now only as rings of small irregularities.

Actually, I'll let you be the judge. I worked over the video file again, this time stacking the best 278 frames. (Maybe 59 weren't enough.) Here's the result, after a considerable amount of sharpening of course:

Maybe it is better.

Today I got equipped for learning to program Atmel AVR microcontrollers. (That's my summer "sideline" project - it has nothing to do with my funded research, but it's too interesting to miss.) Three Butterfly microcomputers and two STK500 development kits arrived at my office. I'll keep you posted as I dig in.

I aim to keep this web site readable on 600×800 screens, but I don't always test it with a browser that narrow.

I think human euthanasia is inherently wrong. But even if it weren't, I'd still be against it because of another issue: old people, especially those without families to stand up for them, will face pressure to accept euthanasia to keep from being a burden. This is allegedly already happening in the Netherlands. Since the pressure is economic in nature, there doesn't seem to be any way to eliminate it.

Spaceweather reports that there may be a fine display of the Northern Lights (Aurora Borealis) in the next day or so. Check the activity level here. If part of the auroral oval goes bright red and comes within 500 miles of you, and it's nighttime and you're out in the country, go out and look at the sky.

What better day than Friday the 13th to analyze something that went wrong?

As you know, Windows uses the file name extension (such as .txt on a text file, or .bmp on a bitmap graphic) to decide how to open the file when you click on it. This information is stored in two places in the Registry:

• HKEY_CLASSES_ROOT
  for the settings that apply to all users. These are created when you install software that recognizes the files. If different software packages disagree, the most recently installed one wins.

• HKEY_CURRENT_USER\Software\Microsoft\Windows\
  CurrentVersion\Explorer\FileExts
  for choices made by the individual user, by right-clicking on the file and choosing "Open With...". These override the settings in HKEY_CLASSES_ROOT. Also, all the choices that have ever been made are remembered as "recommended programs" even if they're dead wrong.

Well... I got a call yesterday that a hapless user of TIP had set his computer to open TIP files with Acrobat Reader.

TIP has nothing to do with Acrobat Reader. When Acrobat Reader gets hold of a TIP file, all it can do is complain that it can't read it.

To straighten out the mess, I wrote a small VBSCRIPT program. You can download it, zipped, here. More likely, though, you'll want to make a similar program customized for your own needs, so here it is:

' VBScript to delete any user-specified "Open With" options for TIP files MsgBox "This script will delete any user-specified 'Open With' options for TIP files." + vbCRLF + _ "TIP files will then open as specified by TIP itself.",0,"" On Error Resume Next Dim WshShell Set WshShell = WScript.CreateObject("WScript.Shell") WshShell.RegDelete "HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts\.tip-d\OpenWithProgids\" WshShell.RegDelete "HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts\.tip-d\OpenWithList\" WshShell.RegDelete "HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts\.tip-d\" WshShell.RegDelete "HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts\.tip-v\OpenWithProgids\" WshShell.RegDelete "HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts\.tip-v\OpenWithList\" WshShell.RegDelete "HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts\.tip-v\" MsgBox "All done.",0,""

Store this on a file whose name ends in .vbs, click on it to run it, and you're done. Note that your security software, if any, will probably object to running it until you give permission.

This young male Anolis carolinensis (American chameleon) is hanging around my back yard this year. He may well be the son of the female that I photographed several times last year. If so, he's more than a year old, not one of this year's babies.

(Don't panic. This is a close-up. His head is about half an inch long.)

I have no idea whether he's innocent or guilty, but the logic of this defense tactic amused me. To put it bluntly:

as any logician worth his salt can tell you. Obviously, Jackson's lawyers aren't minding their 's and 's.

There are two ways to store electricity: in a battery or in a capacitor.

Batteries store electricity by undergoing chemical changes. That means there are real limits to how fast they can be charged and discharged. Capacitors store electrons by attracting them to positively charged surfaces, so they can charge and discharge almost instantly.

The unit of capacitance is the farad, which is enough electricity to deliver 1 amp for 1 second, assuming constant voltage. In real life the voltage declines as the capacitor discharges, but the approximation I just gave is good for the first small fraction of the discharge curve. I thank George Ott for requesting this clarification.

Ordinary capacitors are very tiny (in capacity, that is). Most of the capacitors in a radio or computer are about 0.1 microfarad (0.0000001 farad). In my youth, the biggest ones we ever saw were about 300 microfarads (0.0003 farad), and they were the size of small tomato-juice cans. The joke was that a 1-farad capacitor couldn't exist, and if it did, it would be the size of a railroad car.

Not any more. To make a capacitor hold more electrons, you need multiple layers that are very thin and very close together, so the positive and negative charges will attract each other without actually touching. Manufacturers now use electrolytic processes to make extremely thin layers with very crinkly surfaces so that a lot of surface area can be packed into a small space.

So we now have thimble-sized 1-farad capacitors. In fact, I need to install one in my digitally tuned shortwave radio (vintage 1987) so it won't lose its settings when the clock battery is being replaced.

But that's not all. There are now kilofarad-sized banks of capacitors used for regenerative braking in electric vehicles. Regenerative braking means you use the motor as a generator, so that when you put on brakes, the vehicle slows down and the electric energy is recaptured. Unlike a battery, a capacitor can charge extremely fast, so the generator can put a very heavy mechanical load on the vehicle and capture a lot of energy fast.

What's next? Megafarads?

This may be my best Jupiter picture yet; Satellite II (Europa) is about to pass in front of the planet. Same technique as last night, but somewhat better conditions.

The second picture is the double star Alpha Herculis, as blurred by the atmosphere and by diffraction in the telescope. You can see the color contrast - the brighter star is yellower.

University of Michigan alumni are proud of the large number of double stars that show their school colors (yellow and blue). The astrophysics behind it is that the larger star develops faster, so it starts to reach the red giant stage while the smaller star is still young and bluish-white.

I like to point out that a bit later on in their development, when the larger star has completely burned out, these stars will show the University of Georgia colors (black and red). We just don't see the black ones!

Last night I got the telescope out and added an extension tube (made from kitchen sink trap hardware) behind the Barlow lens to get greater magnification. This is the kind of Jupiter picture I'm getting with this technique. Not bad, is it?

Here are some interesting links I've collected recently...

Bad money management award: Go to Las Vegas with boyfriend, lose $40,000 (charged to your credit card), never make it clear whether the two of you were sharing the debt, and then break up. Yes, it's been done!

I wish right-wing Christians would stop seeing all evolutionary science as anti-Christian. Surely we have a right to study everything God created and see where it leads...?

Equally annoying, though, are those who take a bit of evolutionary science and spin it into a completely godless explanation for everything, as if a few dinosaur bones somehow disposed of the need to think deeply about the origin of the universe, or consider the possibility that it didn't evolve by itself.

You get on very dangerous ground when you assume that anything radically different from your current theories can't be true because "it's not the Scientific Method." Scientific progress has been snagged on that many times in its past. In Copernicus' time, non-earth-centered orbits were "not the Scientific Method."

The key idea is that pathological complainers want vindication and retribution whereas reasonable ones want reparation and compensation, which the legal system is designed to deliver.

That is: The unreasonable complainer wants to convince everyone that he's right, to bring heavy punishment upon his opponent, and to make opposition to his cause disappear. The reasonable complainer merely wants compensation or reversal of perceived harm, while admitting that not everyone will agree ("there are two sides to every issue").

This reminds me of a kind of political activist, the kind who wants to completely obliterate the opposing side, either by force or by creating a climate of opinion in which the other side has no voice. I'm not that kind. I'm the kind who wants errors to be discussed and refuted rationally, not silenced.

The BBC reports an unusual case in which a woman with early-onset Alzheimer's Disease regained the ability to speak, read, and write after going through a basic English course.

This suggests a general tactic: if you lose some knowledge due to brain damage, you can learn it again into undamaged areas of the brain. It's like dealing with a damaged hard disk by formatting out the bad sectors.

This is just speculation and is outside my research specialty. But it suggests the reason for the well-known fact that intellectually active people are resistant to Alzheimer's:

They are constantly relearning their knowledge.

At least, I know I am, and I suppose other people with active minds are like this. I shift my attention between various interests, and I rather enjoy reviewing basic things every time I return to something I've been away from. Or even when I haven't. I do not object to rereading books I've read before, and I enjoy introductory textbooks because I want to see how someone else puts the basics together. That's also why I enjoy writing explicit introductions to subjects.

At the other end of the spectrum, back when PCs were new, those of us who did computer support often encountered middle-aged office workers who were intellectually dead - who were dead-set against learning anything new, and had been that way for years. They were extremely resistant to computers, not because computers were hard, but because they were hard-headed. Are these the high-risk group for Alzheimer's?

Here's the result of last night's (May 1) astronomy session. In the first picture, Jupiter's Satellite II (Europa) is in front of the planet (in the position marked by the arrowheads) and its shadow is the big black spot. In the second picture, 77 minutes later, the satellite has moved off to the left, and (as you can see) Jupiter has rotated quite a bit. These were taken with an 8-inch telescope and Philips ToUCam under mediocre conditions; the best video frames were selected and processed with Registax. The slight twist between one picture and the other is due to not having the camera in the same position.