Red supergiant stars bubble and froth so much that their position in the sky seems to dance around

Making a 3D map of our galaxy would be easier if some stars behaved long enough to for us to calculate the distances to them. However, red supergiants are the frisky kids on the block when it comes to pinning down their exact locations. That's because they appear to dance around, which makes pinpointing their place in space difficult. That wobble is a feature, not a bug, of these massive old stars, and scientists want to understand why.