Sinus Iridium, or Bay of Rainbows, is one of the most charming features of the moon. It was named by the famous lunar observer Giovanni Riccioli on your map drawn in 1651. In those days, of course, it was believed that the dark areas really were seas and that the moon could very well be a world fit for life.

Sinus Iridium is called the bay, but it really is a crater whose wall off was virtually destroyed; Only a few, very low disconnected fragments may be screened. On the other hand the 'wall' mountain is continuous and quite high up there highlighting the Montes Jura, although the outer edge is disturbed by the prominent crater Bianchini. The continuous section is bordered on both ends by Promontorium Heraclides and Promontorium Laplace.

The Iridium floor slopes downwardly from the Imbrium, so that the opposite side is about 200 feet (61 meters) less than the sea level. There is nothing like this anywhere else on the moon. The sequence of events that fornou seems to be quite simple. The sea itself was formed during the lunar time in his honor - the Imbrium - ended more than three billion years, so that is after the Great bombing. The impact that formed Iridum occurred before the great floods of lava.

I said Sinus Iridium is one of the most charming features of the moon. For this you must pick it up at the right time. As the sun rises over him, the mountainous border is illuminated on the one hand, and the tops of the peaks catch the sunlight, while the downstairs is still in darkness. The result is that the wall seems to be out of the moon, beyond the terminator, giving the impression that is completely separate from the main body of the Moon. Lunar observers refer to this as the "Jewelled Handle".

This occurs once every lunation (lunar cycle), well before the full moon, but does not last long, and as the sun creeps on the lower floor is in effect 'picks up' disappears. It is fascinating to follow the changes with increasing altitude of the sun; even a small telescope will show them as well. The floor itself is very smooth, and there are a few fairly well-marked cratereletas.

Sinus Iridium can always be identified when it is illuminated by the sun and save the time of sunrise, the area looks quite common, but at the coming of the next lunation, make sure you will not forget to pay attention to the glory of Jewelled Handle

Adaptation and text: Avani Soares