Tau.Neutrino said:
Avoiding violent neighbors key to planet formation in star clusters
According to the results of a new study, stars orbiting near the centers of massive clusters have a much harder time forming planets than those located at the edge. The discovery was made possible by the powerful viewing capabilities of the Hubble Space Telescope, and could help astronomers unravel the secrets surrounding star formation in the Milky Way.
more…
> No dips in apparent brightness were seen in stars orbiting within four light-years of the cluster’s center. However, 1,500 of the 5,000 stellar bodies observed with masses the equivalent to 0.1 – 5 times the mass of the Sun that were located on the fringes of the cluster tracked light fluctuations. Five percent of this population had dips in light lasting 10 – 20 days before returning to their previous apparent luminosity.
> study of Westerlund 2 revealed that the massive, bright stars that clustered near the center of the vast cosmic structure were mysteriously free of the dense clumps of gas needed to form planets. However, smaller stars observed on the outskirts of the cluster hosted huge amounts of planet-forming material that could settle into an accretion disk.
I had no idea that Hubble was able to do this. Five percent is an enormous percentage for occultation. 10 to 20 days is an enormously long time for an occultation. So the results are unsettling.
As for neighbours affecting planets, a planet is formed in a really short time of the rough order of 0.5 million years. Star clusters are of the rough order of 5,000 million years old. So a planetary orbit is or rough order of 10,000 times more likely to be disrupted after formation by violent neighbours than during formation.