The Hubble space telescope examined a turbulent star-forming region, NGC 3603, ten years after Hubble first surveyed it. And the repeat observation showed that stars were moving in ways that startled and amazed scientists.
According to Hubble's site:
With a mass of more than 10 000 suns packed into a volume with a diameter of a mere three light-years, the massive young star cluster in the nebula NGC 3603 is one of the most compact stellar clusters in the Milky Way  and an ideal place to test theories for their formation... The results for the motion of these cluster stars were surprising: this very massive star cluster has not yet settled down. Instead, the stars' velocities were independent of their mass and thus still reflect conditions from the time the cluster was formed, approximately one million years ago...
Wolfgang Brandner adds: "This is the first time we have been able to measure precise stellar motions in such a compact young star cluster." Team member Andrea Stolte from the University of Cologne adds: "This is key information for astronomers trying to understand how such clusters are formed, and how they evolve."
Here's a close-up of the star-forming region that the team studied:
You can download huge, ginormous versions of these images at the link. [Spacetelescope.org]