What We Have Learned about Stellar Systems and Extrasolar Planets?

How rare are these stellar systems?We do not know yet… but many stellar systems are not made up of just one star. Binary Stars are systems in which physically associated star systems are made up of two stars. It appears that about half of all stars are binary star systems. And Multiple Star Systems have more than two stars. We have found and observed numerous multiple star systems. One such system we see in Scorpius – called β Scorpii – has at least 7 stars . Binary and multiple star systems present challenges for intelligent life.