Captions in the Hubble Space Telescope YouTube channel video Shedding New Light on the Whirlpool Galaxy say:
(visible) Along the dark dust lanes, bright pink nebulae are the birthplace of new stars.
(X-ray, lower energy) Before leaving these stellar nurseries, the most massive stars die in supernova explosions, which heat the surrounding gas to X-ray temperatures.
I'm not very familliar with star formation processes.
These might be considered as separate questions, but I've put them here together because they all refer to the same two sentences in this video, and it's likely that those familliar with nurseries, or wanting to know more about them, will have something to say or learn about all three.
- Do stars tend to leave "these stellar nurseries" after a while, and it's only the short lifetime of the most massive stars that keeps them from leaving before going supernova?
- What impact does the heating of surrounding gas to X-ray temperatures have on the formation and evolution of other stars within a given "nursery"?
- Are there really such things as spatially well defined "nurseries"? Are they distinct and roughly countable, or is this a subjective popular term? Can one point to something and say "this little blob here at x, y, z in the spiral arm of the Whirlpool Galaxy, it's a classic nursery"?