It's a question you might find yourself pondering on a wet weekend - why do raindrops come in so many different shapes and sizes? Scientists think they have the answer after filming a single water droplet falling through space with a high-speed camera.
It shows a raindrop starts as a sphere but bursts into a shower of smaller droplets within a few hundredths of a second.
Firstly the drop flattens out into a pancake shape. As the pancake widens and thins, the onrush of air causes it to hollow out, like an upturned bag.
The bag inflates beyond the ability of the water's tension to hold it together and shatters.
From the Upcoming ueue, submitted by stacy09.
Try this in a vacuum. Oh wow, they're all spheres again...
Every raindrop only differs by it's size
(and of course by the trace elements / compounds the drop contains because the dispersion of said particles is not necessarily uniform in an active weather system).