Learning KML camera views with Ham Radio and Project TouCans

This is so cool! I had a discussion a few nights back about what time of day Project TouCans had been spotted in New Zealand on 20 meters—the few times that its signal had reached out that far. We have a Datasette <add link> database of al the rigs QSOs and RBN spots, so it was simple enough to look up the answer. A few minutes after I started, I had a Google Earth Pro map of—kml file—of all the spots. Using the 'Show Sunlight' feature of app, I quickly realized that all of the spots had been at or near grey line.

Here's the thing though, I wanted to animate how the sun's position on the horizon changed with each QSO, but... Every time I clicked on a new QSO, Google Earth Pro 'helpfully' moved the maps view camera to center the rather large QSO path on the map from space. Not. Helpful.

And this is where the kml concept of camera saved the day! I was able to add a camera tag to the kml file that pointed the map's camera at the exact same specified view of the horizon for every QSO. (Datasette's ability to fill in Jinja templates made trial and error to get this just so super easy.) Here's the tag I used. (The code can be seen here.)

You can see the results below. The video opens with a view of the McLaren Park water tower to help orient viewers, (at least viewer's from San Francisco.) The fixed camera tag then brings us to the view specified by the tag above. I was able to make a video of the sun first rising further to the South as time moved deeper into the Winter, and then rising further to the North after the new year and the onset of Spring! Check it out!

Comments

Cool Math Tricks: Deriving the Divergence, (Del or Nabla) into New (Cylindrical) Coordinate Systems

Now available as a Kindle ebook for 99 cents ! Get a spiffy ebook, and fund more physics The following is a pretty lengthy procedure, but converting the divergence, (nabla, del) operator between coordinate systems comes up pretty often. While there are tables for converting between common coordinate systems , there seem to be fewer explanations of the procedure for deriving the conversion, so here goes! What do we actually want? To convert the Cartesian nabla to the nabla for another coordinate system, say… cylindrical coordinates. What we’ll need: 1. The Cartesian Nabla: 2. A set of equations relating the Cartesian coordinates to cylindrical coordinates: 3. A set of equations relating the Cartesian basis vectors to the basis vectors of the new coordinate system: How to do it: Use the chain rule for differentiation to convert the derivatives with respect to the Cartesian variables to derivatives with respect to the cylindrical variables. The chain ...

The Alcubierre Warp Drive Tophat Function and Open Science with Sage

I transferred yesterday's Mathematica file with the Alcubierre warp drive[2] line element and space curvature calculations to the +Sage Mathematical Software System today, (the files been added to the public repository [3]). If you haven't used Sage before, it's a Python based software package that's similar in functionality to Mathematica. Oh, and it' free. I also worked a little more on understanding the theory, but frankly, I made far more progress with the software than the theory. What follows will be a little more of the Alcubierre theory, plus, a cool Sage interactive demo of one of the Alcubierre functions[1], as well as a bit about my first experience with using Sage. Theory The theory is fun, but it's moving slowly. Here's the chalk board from this morning's discussion Alcubierre setup the derivation using something called the 3+1 formalism which means we consider space to be flat, (in this case), slices that are labelled ...

The Valentine's Day Magnetic Monopole

There's an assymetry to the form of the two Maxwell's equations shown in picture 1. While the divergence of the electric field is proportional to the electric charge density at a given point, the divergence of the magnetic field is equal to zero. This is typically explained in the following way. While we know that electrons, the fundamental electric charge carriers exist, evidence seems to indicate that magnetic monopoles, the particles that would carry magnetic 'charge', either don't exist, or, the energies required to create them are so high that they are exceedingly rare. That doesn't stop us from looking for them though! Keeping with the theme of Fairbank[1] and his academic progeny over the semester break, today's post is about the discovery of a magnetic monopole candidate event by one of the Fairbank's graduate students, Blas Cabrera[2]. Cabrera was utilizing a loop type of magnetic monopole detector. Its operation is in...

Copasetic Flow

Search This Blog