 It has been a long @-@ held assumption that the majority of stars occur in gravitationally bound , multiple @-@ star systems . This is particularly true for very massive O and B class stars , where 80 % of the stars are believed to be part of multiple @-@ star systems . The proportion of single star systems increases with decreasing star mass , so that only 25 % of red dwarfs are known to have stellar companions . As 85 % of all stars are red dwarfs , most stars in the Milky Way are likely single from birth . 
 It <a href='uninflect' title='1'><mark>has</mark></a> been a long @-@ held assumption that the majority of stars occur in gravitationally bound , multiple @-@ star systems . This <a href='drop_aux' title='2'><mark>is</mark></a>particularly true for very massive O and B class stars , where 80 % of the stars are believed to be part of multiple @-@ star systems . The proportion of single star systems increases with decreasing star mass , so that only 25 % of red dwarfs are known to have stellar companions . As 85 % of all stars <a href='drop_aux' title='3'><mark>are</mark></a>red dwarfs , most stars in the Milky Way <a href='drop_aux' title='4'><mark>are</mark></a>likely single from birth . 
It have been a long @-@ held assumption that da majority of stars occur in gravitationally bound , multiple @-@ star systems . This particularly tru for very massive O and B class stars , where 80 % of tdastars are believed to be part of multiple @-@ star systems . The proportion of single star systems increases wit decreasing star mass , soo dat only 25 % of red dwarfs are known to have stellar companions . As 85 % of all stars red dwarfs , most stars in thdailky Way likely single from birth .