The cloud is in fact a lenticular cloud. Lenticular clouds, also known as; altocumular standing lenticularis clouds, are formed when a current of moist air is forced upwards as it travels over elevated land. This elevation and subsequent decrease in temperature causes the moisture in the air to condense and form a cloud.
Lenticular clouds appear to be perfectly stationary, but in fact, this is not the case. These clouds only appear stationary because the flow of moist air continually resupplies the cloud from the windward side even as water evaporates and vanishes from the leeward side. Lenticular clouds can look like they are hovering for hours or days, until the wind or weather changes and the clouds disperse.
This particular cloud also looks really like a piece of cotton wool!
The imaged was snapped by the DigitalGlobes’s Worldview satellite on the 20th of September 2012.