Fogbow plus, Indonesia

Muhammad Rafi Hadytama caught this fogbow at Mount Bromo, Mt. Bromo National Park.

The day, April 28th '13 was full of sightings - "I saw 5 atmospheric phenomena in less than 12 hours from before sunrise until almost midday. I was there to watch the sunrise over the Bromo mountains from one of the ridges. From there I saw a lunar corona, one of the clearest I've seen. Then, when the sun had risen there were crepuscular rays. There was also a belt of Venus. It stretched from between the solar and antisolar points, climbed towards the antisolar point, and then descended again on the opposite site.

Not long after sunrise, we went down from the mountain ridge towards the Bromo mountain itself. Mt. Bromo is quite a unique location. The mountain, along with several other mountains, is located inside a larger crater created from an ancient eruption. So, I went down to that crater which was covered by quite a thick fog. I realized if there's a fog, there should be a fogbow present. And it was! After that there was even a 22-degree radius halo.

All images ©Muhammad Rafi Hadytama

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The huge fogbow, the relatively small ringed glory at its centre and the multi-ringed corona around the sun are all parts of the same phenomenon ~ scattering and diffraction by individual fog droplets.

The droplets are 1-100 micron diameter and sufficiently small that visible light exhibits wave properties and is diffracted when it encounters them.

Freshly formed fog with a narrow particle size distribution is best for optical effects.
The dark wedge of the earth's shadow in the west topped by the pink Belt of Venus.

The Mt Bromo complex is active and has erupted recently.

IRIS Mie simulation of a glory and fogbow from droplets with a mean diameter of 32 micron but a wide spread of sizes.

The glory and fogbow are thereby smeared out and show fewer rings or supernumerary fringes.
Corona from the same droplets