Eclipse of the Radio Sun
Joachim Köppen Kiel Sep 2017

Some brief explanations

This simulation shows how the radio flux from the Sun changes during an eclipse by the Moon. The Sun's radio emission comes from three contributions: The image on the left displays the motion of the Moon across the face of the still-standing Sun. The path of the Moon across the solar face is described by the offset in vertical direction and the angle with respect to the horizontal direction, to allow simulation of total and partial eclipses. Also, one can take into account that the Moon's diameter differs from that of the Sun, and to deal with annular eclipses. The blue circle indicates the half-power radius of the antenna beam, which has a gaussian profile.
The plot on the right shows how the fraction of the radio flux changes with time, i.e. the position offset of the Moon. Since the faster Moon overtakes the Sun in its travel on the sky towards the East, the Moon moves from left to right in the image, but the curve starts from the left hand side.
Vertical magenta lines mark the first and last contact of the optical eclipse.
The controls are:
Y offset [Rsun=0.25°]
path angle
Disc brightness
Shell brightness 1
Shell source: Rinner/Rsun
brightness (shell=1)
HPBW [°]

Mouse position:

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