What happens when a raging cyclone as wide as Earth bumps into another storm twice as large? The answer lies in the midnight sky. Two storms on Jupiter--the Great Red Spot and Oval BA--are having just such a close encounter. Amateur astronomer Anthony Wesley sends this picture from Exmouth, Australia:

Red Spot and Oval BA
© Anthony Wesley
The bigger storm is the Great Red Spot, which has been swirling around Jupiter for centuries. The smaller is upstart Oval BA, which formed less than ten years ago. Because the storms travel around Jupiter at different rates, they pass one another periodically, approximately every two years. And when they do ... not much happens. Previous encounters have shown, surprisingly, that the two colossal storms can converge and emerge in tact. Could this time be different?

"Oval BA and the Great Red Spot will be passing one another in the days ahead," says Wesley. "I plan to monitor developments."

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