Something beyond visible universe detected?

Sci­en­tists have meas­ured an un­ex­pected mo­tion in dis­tant clus­ters of ga­lax­ies—pos­sibly caused, they say, by the gravita­t­ional pull of some­thing out­side the vis­i­ble uni­verse. “We nev­er ex­pected to find an­y­thing like this,” said lead re­search­er Al­ex­an­der Kash­lin­sky of NASA’s God­dard Space Flight Cen­ter in Green­belt, Md.