Astronomers finally know why stars born from the same cloud aren't identical twins 

 Astronomers finally know why giant binary stars born from the same collapsing cloud of gas and dust can be "non-identical twins" with different characteristics and planetary systems. 

https://cdn.mos.cms.futurecdn.net/QU2qAhMKGqNW9ub7p7z68c.png

https://www.space.com/binary-star-gas-cloud-chemical-composition