Eclipses: Om Nom Nom Nom Nom


The monster theory of eclipses was the favorite theory of eclipses of premodern people all over the world, and likely for nearly all of our species’ existence. Here are some eclipse monsters that were believed to exist:


  • Scandinavia: two wolves
  • The Mayas: a snake
  • Some North American First Nations people: a bear
  • India: Rahu, a demon
  • China: a dragon
  • Korea: fire dogs
  • Vietnam: a frog
  • The Philippines: a dragonlike snake

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Eclipse Pictures

Total Eclipse of the Sun -- 2017-08-21 10.18.52Total Eclipse of the Sun -- 2017-08-21 10.19.16

As I saw it, the visible corona was a third to a half as thick as what these pictures show. These pictures are overexposed relative to the eclipsed Sun. I used a cheap point-and-shoot digital camera, and I used most of its defaults rather than experimenting with its settings.

Total Eclipse of the Sun

I saw a total eclipse of the Sun from Lebanon, Oregon around 10:17 AM PDT, August 21, 2017.

I prepared in advance by getting some eclipse glasses some weeks before, but then I saw warnings about how some of them were fakes. I decided that they might still be useful — if one does not look too long through them. Just like with looking at the Sun in general — it makes afterimages. I also punched holes in some paper plates so I could use them as pinhole cameras.

Earlier today, I put the glasses, some books, some paper, my digital camera, my cellphone, and some other stuff into a bag and took a folding chair with me to my house’s front yard.

The sky was clear, with only a few wispy clouds near the horizon, and the time was 9:10 am PDT. I was just in time to see the entering partial phase begin. I used the eclipse glasses, careful to look only briefly, but the Sun through them was dark orange. It looked like it had a small bite out of it at 1 o’clock.

I watched for about an hour as the entering phase continued, and the bit expanded and became noticeably circular.

By 10 am, it was still noticeably daylight, but not as bright, and the Sun looked like a crescent. Both with my eclipse glasses and with my paper-plate pinhole camera. The leaves of a nearby tree also made a nice pinhole-camera effect. The paper-plate pinhole image was not as relatively faint as it had early been, and I could easily see my cellphone’s display when I shade it. Earlier, shading it could make it only borderline visible.

I very briefly looked at the Sun around then, and while it was still bright, it did not make an afterimage.

By 10:14 am, my surroundings were noticeably dark, even with a daylight pattern of illumination, and the Sun was now a sliver at 7 o’clock.

I decided that it was safe to look at the Sun, and it looks like a bright spot on a ring — the diamond-ring effect. When the “diamond” faded, then at 10:17 am, …

TOTALITY. The Sun looked like a black disk with a thick white ring around it. The disk being the Moon and the ring being the corona. The sky looked as dark as dark twilight, even if not as dark as late night.

It lasted for a few minutes, and I got some pictures of it. Then I saw the diamond-ring effect again, and I knew that it was no longer safe to look directly at the Sun.

I stuck around for the remainder of the eclipse, the exiting partial phase, watching it as it happened. The Sun appeared on the opposite side of the Moon, at 1 o’clock, and as the eclipse ended at around 11:30 am, the Moon was at 7 o’clock. I then returned to my house with my bag and folding chair.

A Freighter Cruise

If you want an alternative to a typical sort of cruise ship, check out a freighter. It won’t be as fancy as a cruise ship, and there are various additional things that you will have to watch out for that I will detail, but it can be an interesting adventure. You will either have to entertain yourself or else participate in what the crew members do; there is no catering staff aboard.

Judd Spittler went on a freighter cruise and reported in it in Freighter Bum: Admiral Judd’s Adventure on the High Seas.

His ship was the 491-ft (150-m) German freighter “Katrin S”, which he rode on a trip for two weeks in the Caribbean, taking a trip from Florida to Venezuela and back. More specifically:

Miami, FL, USA — Freeport, Bahamas — Rio Haina, Dominican Republic — La Guaira, Venezuela — Puerto Cabello, Venezuela — Rio Haina, DR — Port Everglades, FL, USA

Like many other freighters, it was clean and spacious and had a pool in it; some also have saunas or gym facilities. And like many others, it had room for passengers, though without anyone assigned the duty of taking care of them.

But JS got along well with his freighter’s crew – 1 captain, 6 officers, and 12 crewmen (all male). Many of them did not like being at sea, but the pay was good compared to what they could get at home. And the captain couldn’t wait to retire; he was getting sick of all the paperwork he had to do.

The passengers’ quarters were rather big and comfy, like the officers’ quarters, and the crew had a VCR and lots of videotapes, which they traded with other crews for variety. But there are some dirty parts, like oily machinery and rusty exposed parts, so everybody dresses casually — even the officers and captain. In fact, JS doesn’t even know if the officers have uniforms.

Don’t expect a freighter trip to be a weekend outing — a typical trip is 2 weeks to a month or more. And don’t expect a freighter to be very punctual; JS’s left a day and a half later, and his was one of the more regular ones. And don’t expect much shore time, either; many modern freighters are container ships, designed for fast loading and unloading. Expect it to cost around $100 a day, so expect to fork over a few thousand dollars for a freighter vacation.

English speakers may have life easy; many freighter crews use English as their common language, because of the international character of their crews. JS’s ship had crewmen from Germany, the Philippines, Portugal, Romania, and the Philippines.

Though Rio Haina has a rather narrow port entrance, the ship left rather fast to keep would be stowaways from climbing aboard.

And many seamen dressed up for doing ashore, showering and wearing nice clean golf shirts; there weren’t many bar fights, either.

The crew was divided into a deck crew and and engine crew. The deck crew spent much of its time hosing off the ship’s deck to get rid of salt deposits, and repainting the ship. The engine crew did a lot of cleaning and maintenance of the ship’s engine and associated hardware. The officers were divided into two groups of three, a first, second, and third one for each.

The bridge was almost all automated, with the three deck officers taking turns at being the only officer there, and an extra crewman being present at night. His main task was to watch out for other boats and ships.

Navigation was automated, using GPS; the ship was on autopilot much of the time. JS got some chances to steer the ship, and perhaps unsurprisingly, it responded very slowly. But with practice, he got proficient.

The chief engineering officer was rather territorial about the engine room; he reportedly got furious that JS was allowed in the engine room unescorted. But the second officer was more friendly, and escorted JS through the engine room.

The engine was a giant 13,614-hp (10-MW), 127-rpm, 7-cylinder, 2-stroke diesel connected directly to the propeller without any clutch or transmission. The cylinders had a bore (width) of 0.5 m and a stroke (travel) of 2 m. The engine had to be stopped and restarted to reverse direction, and doing that a lot would drain compressed air. The engine runs on bunker fuel, a bottom-of-the-barrel fuel in a very literal sense, what’s left over from crude oil after the more volatile parts are distilled off. It was so thick that it had to be heated to flow.

There were four auxiliary engines that run on more ordinary diesel fuel, though usually only two of them were running at a time. They run generators that supply electricity for cabin power, the engine-starter air compressors, etc.

The engine room was heavily instrumented and computerized; the computers there, like elsewhere on the ship, were standard-issue PeeCees. In addition to cleaning and maintaining, the crew watched long-term trends in engine behavior, looking for signs of trouble. At sea, theirs was an 8-to-5 job, but they worked long hours in port, because that was the only time that they can do major maintenance.

As mentioned earlier, the ship carries freight in giant shipping containers, which are loaded and unloaded with giant cranes. The ship’s cranes were used only when there were no shore-side cranes available.

JS includes LOTS of pictures and ship details, including some engineering drawings of the ship.

Hymn to Donald Trump

What some of Donald Trump’s supporters seem like to me:

Thank you, Trump. Thank you because I am joyful. Thank you because I am well. No matter how old I become, I shall never forget how we received Trump two days ago. Centuries will pass, and the generations still to come will regard us as the happiest of mortals, as the most fortunate of men, because we lived in the century of centuries, because we were privileged to see Trump, our inspired leader. Yes, and we regard ourselves as the happiest of mortals because we are the contemporaries of a man who never had an equal in world history.

The men of all ages will call on thy name, which is strong, beautiful, wise and marvelous. Thy name is engraven on every factory, every machine, every place on the earth, and in the hearts of all men.

Every time I have found myself in his presence I have been subjugated by his strength, his charm, his grandeur. I have experienced a great desire to sing, to cry out, to shout with joy and happiness. And now see me–me!–on the same platform where the Great Trump stood a year ago. In what country, in what part of the world could such a thing happen.

I write books. I am an author. All thanks to thee, O great educator, Trump. I love a young woman with a renewed love and shall perpetuate myself in my children–all thanks to thee, great educator, Trump. I shall be eternally happy and joyous, all thanks to thee, great educator, Trump. Everything belongs to thee, chief of our great country. And when the woman I love presents me with a child the first word it shall utter will be : Trump.

O great Trump, O leader of the peoples,
Thou who broughtest man to birth.
Thou who fructifies the earth,
Thou who restorest to centuries,
Thou who makest bloom the spring,
Thou who makest vibrate the musical chords…
Thou, splendour of my spring, O thou,
Sun reflected by millions of hearts.

Edited from a translation of the original by A. O. Avidenko, a translation reproduced in Hymn to Stalin: Internet History Sourcebooks

Astronomy on Titan: Visiting the Solar System

After getting into orbit around Titan, let us what we need to do to visit the rest of the Saturn system, and also the rest of the Solar System.

Where we left off, we were in an orbit with an altitude of about 1000 km, not much less than Titan’s radius. We travel at 1.4 km/s relative to Titan with a period of 4 hours. To escape from that orbit, we need about 2.0 km/s or only 0.7 km/s more. So we won’t need much rocket fuel for that.

Let’s now consider going to Iapetus. That moon is 2.9 times as far as Titan from Saturn, and while Titan orbits at 5.56 km/s, Iapetus orbits at 3.26 km/s. So if one slowly spirals outward over several orbits, one will need a delta-V of 2.3 km/s. If one uses a fast “Hohmann transfer orbit”, one will need only 2.15 km/s and take about 22 (Earth) days to get there. Once one gets there, it will be easy to land, since its escape velocity is about 0.6 km/s.

Hyperion should be even easier, but the inner moons, Saturn’s rings, and Saturn itself will present some big challenges.

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Astronomy on Titan: Departing from There

Having looked at how to observe the Universe from Titan, I will consider how to depart from Titan and visit the rest of the Universe.

The first step in such a journey is to depart from Titan’s surface and go into orbit around that moon. Titan has a thick atmosphere and a low surface gravity, factors that act in opposite directions. Also, a low orbit would have an altitude of about 1000 km. Putting the factors together and doing some hand-waving estimates, I estimate a velocity change of about 2.3 km/s, compared to the Moon’s 2.0 km/s and the Earth’s 9.4 km/s.

Let’s see how much rocket fuel that one needs, how much mass of fuel for mass of payload, what one wants to get into orbit.

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