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There are many conflicting requirements: gain of the antenna size of antenna directionality of antenna. bandwidth To make antenna efficient you want it to have a narrow beam to direct most of the energy to the satellite. This implies your antenna will be highly directional. For a hand held device it is almost impossible to aim the beam reliably when the ...


SpaceX has been launching Starlink satellites in large quantities and a recent launch may be the satellites you've seen. On release they have close spacing and slowly separate to the appropriate orbits. According to the website, Heavens-Above, the most recent launch was Starlink 5 on 18 March 2020. The site describes the visible satellites as "string of ...


I found it. It was NOSS 3-1, a satellite pair. Found it through heavens above. The pair also explains the apparent tumbling. However, it seemed much brighter than 4.1, but it‘s definitely it.

2 doesn't show anything that quite matches your specification. There was an H-2A rocket body (i.e. upper stage) overhead at 7:46 going from NE to ESE; there was an SL-16 (Zenit) rocket body a couple of minutes later going ESE to N. Tumbling rocket bodies can vary considerably in brightness.


Let me put this in a different frame. First recall that magnetic fields also store magnetic energy: $$ E_{mag} = \int_V H. B\, dV $$ Now, from Lagrangian mechanics, note that: $$ L = U-V = E_{mag}+E_{grav}-\frac{mV^2}{2}-\frac{\omega^TI\omega}{2} $$ And let's forget some dissipative effects and the angular terms for now. Recalling Euler-Lagrange's ...

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