Solar angle protractor
With its bubble level, note the angle that the sun makes in relation to the horizon.
Hold in your hand!
α measurement
For a successful flight, it is useful to know the angle α that the sun makes with respect to the horizon, so that another flight can be reproduced under the same conditions,
whatever the time of year. The rays of the sun cross the same layer of atmosphere in summer or in winter for the same angle α.
This is an approximation, however sufficient for the balloon / solar balloon activity.
Example northern hemisphere
Manufacturing
The basis for this measuring instrument is a schoolboy's protractor. A multitude of models exist, which is why I am not able to produce manufacturing plans.
Below is the description for making a solar angle protractor from your own material.
Angle protractor Ø120. Aluminum angle 20x20xthickness 1. Aluminum plate 15xthickness 2. Aluminum tube Ø6xthickness 1. Threaded rod M3.
M3 screws. M4 screw. Nuts. Washers. Cylindrical bubble level Ø15. Adjust the horizontal using the bubble level.
Schematic diagram for height (α angle) and azimuth (β angle) adjustment.
Set the azimuth (β angle). The shadow of the vertical M3 threaded rod must merge with the longitudinal axis of the assembly.
Record the height (α angle). Center the shadow of the horizontal M3 threaded rod on the Ø6 tube.
Here, we can take an angle of 55° (July 6 - 10 a.m. UTC - latitude 46.7°N).
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