Why it's hard to form planets in the middle of a star cluster

Scientists think most stars in our galaxy play host to planets, but 20,000 light-years away, a dense cluster of stars is proving to be the exception to that rule.

Why it matters: New research from scientists using the Hubble Space Telescope found the core of the star cluster Westerlund 2 is inhospitable to newly forming planets.

• Researchers think that the dearth of worlds is likely due to immense radiation from huge nearby stars blowing away any planet-forming dust clouds.
• Moving away from the core of the cluster, however, disks of gas and dust that give rise to planets seem plentiful.

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