sat plugin: flares due to nadir oriented panels of a selected satellite

[axd1967]

Is your feature request related to a problem? Please describe. Visualisation of potential satellite flares (eg Starlink)

Describe the solution you'd like When selecting a satellite, the program plots the topocentric direction of solar reflection for that satellite, assuming a reflective panel aimed at sat's nadir.

When the satellite crosses this point, a flare could be expected. The point changes over time, related to Sun's altitude.

An extension is to allow for an angle within which a flare can be expected; this would result in an ellipse-like shape around the point.

An extension to this use case would highlight all displayed sats that reflect sunlight via a nadir oriented surface within a specified angle (eg 5 degrees) towards the user (the user is within a cone of N degrees from the reflection beam). This might require e.g. connecting each reflecting sat with the spot where the flare will occur, so that the user can identify the origin of the flare. Flares of reflections that already occurred could be drawn in a different color.

Describe alternatives you've considered

Additional context

thread http://www.satobs.org/seesat/Nov-2022/0039.html

https://en.wikipedia.org/wiki/Satellite_flare

(not in scope of this issue, yet so attractive: http://www.satobs.org/seesat/Jan-2022/0015.html)

[github-actions[bot]]

Hello @axd1967!

Thank you for this suggestion.

[gzotti]

The code for Iridium flare is still in the repo, just deactivated because those reflective satellites have been deorbited. Where would one get the information whether a particular satellite is equipped with such antenna, and how bright reflections from this one antenna would become? I am no longer aware of satellite observers looking forward to predictable flashes, but I know many astronomers being afraid of the satellite pest caused by some big egocentrics.

[alex-w]

SkyMed has bright flashes as example - it's in my long-term todo list