One of the mysteries of Venus is the strange patches in the clouds that show up in ultraviolet light.
As BBC Online discuss [with a nice mention of OxSciBlog] Oxford's Fred Taylor and colleagues report in Nature on observations from Venus Express that shed light on this phenomena. I asked Fred about Venus and its strangely seasonless climate:
OxSciBlog: What do these UV patterns tell us about the atmosphere of Venus?
Fred Taylor: The features seen on Venus in ultraviolet light have been a puzzle to astronomers for nearly a century. The Venus Express spacecraft has revealed the structure in the clouds that produces them, and how they result from complex meteorological behaviour on the Earth's nearest planetary neighbour.
OSB: What can they tell us about Venusian weather?
FT: The cloud patterns outline the weather systems, just as they do on Earth. It is fascinating the way the meteorology on Venus is similar to Earth in some ways, and different in others. Some of the differences are due to the slow rotation of Venus compared to Earth, and some to the great depth of Venus's atmosphere. Other features we don't understand yet, like the detailed nature of the great vortices at the pole.
OSB: How do they help us compare and contrast the Southern and Northern hemispheres?
FT: Unlike the Earth, Venus's atmosphere is nearly symmetrical about the equator - the two hemispheres behave very similarly. In other words, Venus has no seasons. This is explained by the small tilt of the rotation axis - less than 2 degrees, compared to about 23 degrees for the Earth.
Read more about Volcanic Venus on the OxSciBlog.
Professor Fred Taylor is based at Oxford's Department of Physics.