While attention was on Jupiter due to the recent July 19 impact of a comet, something strange was happening on Venus at the same time. For some mysterious reason, a white spot has formed on the southern-hemisphere clouds of Venus. It was noticed by amateur astronomer Frank Melillo of Holtsville, New York on July 19 but was largely ignored because of the "bigger" and unprecedented event on Jupiter.
According to Sanjay Limaye, planetary scientist of the University of Wisconsin-Madison, it's not the first time that this has happened on the clouds of Venus (left; European Space Agency), in effect saying it's a normal occurrence. Nevertheless, the cause of such whitenings remains unclear. Limaye says this event is unique in that it happened in a smaller area.
After receiving Melillo's report, other astronomers and the Venus Express spacecraft of the European Space Agency took a look at it. The result is a series of pictures that show how the white spot changed in time. The photographs showed that the white spot appeared four days earlier than the report by Melillo. Theories about it range from volcanic eruptions to effects of a coronal mass ejection from the Sun.