Other planets that we have so-far detected. There are no doubt countless more planets that out current technology cannot detect so easily. It may be that all t

Other planets that we have so-far detected. There are no doubt countless more planets that out current technology cannot detect so easily. It may be that all those with continents are small enough that they slip though the detection net. We should probably hold off on the comparisons until we are able to readily detect earth-sized planets around similarly-sized stars to ours. Then we can talk about whether our arrangement is or is not rare.