La Palma

La Palma is rugged.

One of the finest astronomical sites on Earth hides serenely above those clouds.

The people of La Palma are proud of their astronomical connection — here’s a signpost from a roadside viewpoint:


There are about 20 large telescopes on the top of the North Peak.

On September 19, 2021, a major volcanic eruption took place on La Palma.  Lava flows wiped out a relatively small part of the island, but our guide told us ash falls covered a large area — “like very fine black flour”. We didn’t see any sign of the ash seven months later. The eruption wasn’t a severe problem for the large telescopes, though a couple of instruments were affected.

La Palma is also very green.

Hikers in a deep green canyon

It’s a short hike to the waterfall up ahead:

Note the green metal railings, the rectangular cave mouth, and the concrete structures going back further up the canyon– this is a developed park, not a wilderness area. The canyons are deep and rugged but still modified by human occupation.

This canyon has been developed as a source of fresh water but retains a wild scenic character — a mix of community park, water project, and wilderness area. Further down the trail was an open rectangular water tank, 10′ x 10′ x 6′ deep, with the same damp old concrete.

On the trail to the waterfall

Down the canyon, the almost vertical walls were terraced.

Terraces in the canyon wall

(The picture is misleading. It’s perhaps a hundred feet from the flowers in the foreground to the trees across the canyon; the canyon floor is a hundred feet below.)

A mile or so further, the canyon widens, and the terraces are well-tended:

People have been living here for a long time.

Well, there was more, but this post is too long already. La Palma was my favorite of our stops. It is unlikely we will ever be there again, but if I had another life, I would like to spend more time there.

Grammar Gripe

There is a rule about punctuation I can’t bring myself to follow: “In the United States, commas and periods go inside the quotation marks”. I just broke it there.

The rule I follow is that everything inside the quotation marks is part of the quote:

Here is a quoted fragment of text: “a quoted fragment of text:”.

The “:” inside the quotes is part of what is quoted. The “.” defines the sentence structure.

Or consider:

A. The final “word”.


B. The final “word.”

B looks strange to me — the period is part of the sentence structure, not part of the quoted text, so B is a sentence without its final period. It should be

B. The final “word.”.

if you want to quote


What about even stranger cases:

Brian flew to a place in the clouds where punctuation marks included  “%$^&”.

I think like this because of long exposure to computer languages, where the syntax rules are much more regular. You can always distinguish between the syntactically live use of punctuation and syntactically lifeless punctuation inside quotes. Any text can be unambiguously quoted.

English usage is like a woodland path — it is where it is because that’s where people walked. For many years I walked somewhere else, and I’m very comfortable there.

Rough Seas

Last night was a rough passage for a landlubber like me, with strong winds and 10-foot swells. The night before, the ship was rocking, but last night it was pounding. The captain apologetically announced that conditions would be a bit uncomfortable, but our situation wasn’t bad, and just enough to remind us that we were really at sea.

Of course, it can get much worse — here’s a youtube video where it was substantially worse — you can hear an authentic example of the emergency signal (7 short blasts, then a long one).

The rocking motions are roll, pitch, and yaw, like an airplane. Yaw wasn’t noticeable, but roll and pitch were strong enough to make it impossible to walk in a straight line. Roll and pitch are rhythmic vertical motions, with the ship’s buoyancy trying to return to level. Roll had a period of a few seconds; pitch had a longer duration. (On the other hand, yaw is a horizontal rotation with no vertical component and no passive returning force. A yaw motion is essentially a tiny course change that requires autopilot or human correction to undo.)

Of course, all these motions combine unpredictably. The ship moves as a rigid body in a complex dance, and as long as it’s not too bad, you can enjoy it.

However, when conditions got slightly worse, the water slapped the hull explosively, and a new form of motion manifested. Rather than moving as a rigid body, the ship vibrated like a colossal gong, with a pitch of about 1.5Hz. This ringing sometimes persisted for several seconds (though generally less than 10 seconds). I suspect this vibration came from the waves striking the ship’s bow at an angle.

When the ship slammed even harder, though, sometimes there was a higher frequency vibration, maybe 5Hz, that decayed within 2-3 seconds — a violent shaking motion that rattled small objects.

These vibratory modes must be from the flexing of the ship itself, and the frequencies probably reflect the natural resonant frequencies of the ship.


Radar dome on top of Madeira
This is the nearly highest point on Madeira. It sports a radar dome.

Funchal, Madeira, Portugal.

You could teleport here from a street in Lisbon and not notice any change. Lisbon on an island. But we spent almost no time at Funchal, the main city and the main port, and instead, we boarded a bus for our package tour, “Scenic Madeira”. After a 45-minute harrowing bus ride over very narrow, very curvy mountain roads, we arrived at Pico do Arieiro, the highest point you can reach by car. The view was exquisitely scenic, but the wind was fierce and icy and more than I could bear — I stayed inside the coffee shop.

On the way back, we stopped at a wine shop to sample some Madeira. Very sweet.

Smallwine glasses

Endless Sea

In April 2022 we took a cruise, a highly privileged cruise. A mental health cruise. Ten choppy days, mostly island hopping, leaving from Lisbon. Then Madeira, three Canary Islands — La Palma, Tenerife, and Lanzarote — Gibraltar, Cadiz (Seville), and finishing at Barcelona.

Endless Sea out my Window
Endless Sea out my window

This is what I see out my window as I type this. The night before last we were in Lisbon, jet-lagged and exhausted.  Now we are roughly halfway to Madeira, and far from land. I slept ’til noon, and woke up groggy. Now, with three cups of coffee, I feel much better.

The internet access on the ship is fair — they block streaming video, but text and stills load OK. Sufficient to work on this blog, at least. I brought a couple of ebooks on WordPress, and I’ve been skimming them. I’ve learned that I’m doing it all wrong. I should pick a topic and stick to it instead of just rambling on with whatever interests me at the moment. That advice rings true — it describes the kind of blogs I follow, anyway. So I guess this blog is doomed to obscurity.

The ship is the venerable RSS Voyager — our fifth cruise on the Voyager. It’s our second cruise since the pandemic. Masks are required unless you are in your stateroom or eating or drinking. Most of what we do outside the stateroom is eating and drinking, so not a burden. Unlike in the yahoo areas in the States, compliance is near 100%, and it was nearly 100% in Lisbon. At lunch, somebody complained that they asked for a glass of water, and it took forever to arrive. White privilege vented at an Asian waitress, a jarring note.

There is a soft slow creaking sound as the ship rocks in the following swell. An almost unnoticed sound of waves and wind, and a quiet hum from the motors. It’s very quiet. Leaning forward with my elbows on the desk and my chin in my hands, I think I should take a nap.

M97 and M108

M97 and M108
M97 and M108

M97 is also known as “the Owl Nebula” — you can barely see the two eyes. M108 is known, for some reason, as the “Surfboard Galaxy”. North, by the way, is to the right.

M108 is also the galaxy on the left edge of the images I posted yesterday. The image yesterday was a failed attempt to integrate 14 separate exposures; the image above was a successful attempt to integrate 16 (different) exposures. Yesterday’s failure haunts me — I worked on it for hours. Here’s a cut from the above image of approximately the same aspect:

Edge of M108
Edge of M108

Striking, to me at least, is that there were two stars in this region in yesterday’s image, but only one here. I’m pretty sure that this image is a better reflection of reality…  Perhaps that is a clue about what I was doing wrong!


A colorful mosaic; an extreme magnification of an image of space at the edge of a galaxy. Two prominent stars, some bright spots that are probably just defects in the sensor, or maybe where a cosmic ray hit and produced a single bright flash. Mostly, this is just visual noise. Noise

Here’s a different version, where the individual pixels have been smoothed:


A prettified instantaneous snapshot of the quantum noise roiling across the sensor. Perhaps if I could make a movie, these would be tiny agitated multicolored ripples. But the two stars would remain, hard reminders of a real world, and the brightness at the right edge would also remain, testifying to that galaxy — M108, I’ve heard — off-screen to the right.

Edit: I’ve since discovered that one of those stars must be an image-processing artifact. So much for reality.



Another galaxy floating in splendid isolation. According to this Wikipedia article it is part of the M94 group, which is loosely bound to the extent that some members are just “moving with the expansion of the universe”.

Take that, Putin!

Tadpole Nebula

Tadpole Nebula
SH2-236 — Tadpole Nebula

The “tadpoles” are slightly lower left of center.  There are two of them: bright structures rather than the usual dark spots.

Iris Nebula

Iris Nebula
Iris Nebula

I imagine this was a particularly dirty explosion, throwing dark dust clouds and obscuring large patches of a dense starfield. If you look closely, there is a gritty quality to the image.