Why Some Stars Never Form Planets

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The planetary paradigm has shifted so quickly and so radically in the last quarter century that is easy to forget that only a few decades ago, one would be hard-pressed to find any professional astronomer who would stake their careers on the idea that most stars harbor planets. But although the overwhelming majority of stars may harbor some form of planet, not all stars are capable of forming planets.

During the first two decades of looking for planets that circle stars outside our solar system, detections came in dribs and drabs. But NASA’s Kepler telescope changed the paradigm completely when based on Kepler data, astronomers made the statistical case that at least half of all stars in our own Milky Way galaxy must harbor planets.

But what about stars that will forever remain barren of planets?   The cosmos appears to have more than a few of those. 

Thus, here’s a quick survey of which stellar spectral types are best suited to form planets over the range of O, B, A, F, G, K and M stars.

O- and B-type stars —- the most massive, hottest and short lived stars in the cosmos.

We know essentially nothing about the planet population orbiting these stars because their large size, brightness, and spectral properties make the detection of exoplanets using current techniques nearly impossible, Benjamin Fulton, an astronomer at the NASA Exoplanet Science