@brianbilston a lifetime of egrets

Even in the TRON future they still have the problem that "ps aux | grep" includes the grep itself.

Here's the cropped video of the flashing light on the crane; the first few seconds are real time and then the video slows to 240fps.

The crane across the river from my house has been bothering me for the past year with a flickering light, so I did what any reasonable person would do: shoot a 240fps video of it to see if it was encoding data. The flashes from different samples seem to align very well, so maybe pulse width modulated?

Controversial opinion: navigation is much easier with decimal math instead of minutes and seconds. I make far fewer mistakes with base ten than sixty, plus 0.01 is slightly smaller than 1/60. And besides 1' equals 1 nautical mile only at the equator so it's not really very useful on the rest of the planet.

Intercept success! The Lines of Positions from two Sun sights converge on the actual location (within a few nautical miles at this scale)

Fixed the LHA computation to use the DR longitude instead of the actual longitude and now the lines of position converge very close to the actual location!

That's better, although now they all converge at the actual latitude but the dead reckoning longitude position.

Something is wrong with my math. The LOP aren't lining up correctly.

Bus 22 has an error on /dev/sda1

Math is hard. Let's go sailing.

The goal is to replace the six pages per latitude of the Pub 249 sight reduction tables with a single chart that can be printed two to a page.

Since the Zn result is symmetric around LHA and it is important to have a higher-accuracy on the Hc height, I've split the chart into two so they can be read separately

Friends don't let friends mix degrees and radians.

Expanding the declination range to +/-60 and the LHA to +/-180 makes the globe more obvious and shows the polar regions.

That's better (and actually usable for measuring Hc and Zn for a given latitude, declination and LHA)

That's not right, but it's not wrong either...

Making lazy coffee this morning

How many is too many slides for my forty minute talk on celestial navigation for #39c3? Currently around fifty and still have a few diagrams to make.
(My usual pace is thirty seconds per image, so I think I still have room for more)

The server transfer from the train to the cargo bike was a success.