There have been many speculations about this, but it all comes down to the fact that these planets are larger than Jupiter and humans would be badly crushed under the gravitational fields of these planets, even assuming they had a solid surface to stand on. They also orbit so close to their parent stars that temperatures are often above the boiling point of water for most of their year.
Even if they had earth-like satellites, these two would have awful...and lethal...extremes of temperature swings. The gravitational perturbations these massive planets make would probably eject any smaller earth-like planets in their star's habitable zone (between 0.5-2 AU in the figure above) . I don't think these recently-detected solar systems are the right places to find earth-like planets at all...certainly not ones suitable for humans. But we have only started this search, and as instruments become better and better, we will be able to see more stars with planets like our own.
Copyright 1997 Dr. Sten Odenwald
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