VCSE - Sinus Iridium - Bognár Tamás - 2007
VCSE – Sinus Iridium – Bognár Tamás – 2007



Subject: Sinus Iridum  (Latin for “Bay of Rainbows”)
Classification: Sinus Iridum is a plain of basaltic lava that forms a northwestern extension to the Mare Imbrium on Earth’s moon. It is surrounded from the northeast to the southwest by the Montes Jura range. The protruding part of the range at the southwest end is named Promontorium Heraclides, while that at the northeast end is called Promontorium Laplace. This bay and the surrounding mountains is considered one of the most beautiful features on the Moon, and is a favorite among lunar observers.
Date/time: 2007.06.25.
Equipment: 76/900 Newtonian
Eyepieces/Mag. Plössl 8mm, 112x
Transparency/Seeing: 3/5, 7/10
Humidity: alacsony, enyhén párás levegő
Wind: none
Moon phase:
Observing Loc. Hungary, Zákány,  N46°14′ 59,2″ E16°57′ 15,3″
Observer: Bognár Tamás


Sinus Iridum is formed from the remains of a large impact crater, which was subsequently flooded with basaltic lava, inundating the “sea” wall. The bay itself does not contain any notable impact craters, but does include the satellite crater Heraclides E in the south, Laplace A along the eastern edge, and Bianchini G in the north. The surface is level, but is marked by a number of wrinkle ridges (dorsa).

The selenographic coordinates of this bay are 44.1° N, 31.5° W, and the diameter is 236 km.The feature was given the Latin name for the Bay of Rainbows by Giovanni Riccioli.