Gaia EDR3 triple stellar systems within 100pc

The motion sense of the inner and outer pairs is almost uncorrelated, implying a mean mutual inclination of 83.1{deg}+/-4.5{deg}. The median mass of the most massive component is 0.71M_{sun}_, and the median system mass is 1.53M_{sun}_. In a 0.69 fraction of the sample the primary belongs to the inner binary, while in the remaining systems it is the tertiary.

A 0.21 fraction of the inner subsystems are twins with mass ratios >0.95. The median outer mass ratio is 0.41; it decreases mildly with increasing outer separation. Presumably, these wide hierarchies were formed by collapse and fragmentation of isolated cores in low-density environments and represent a small fraction of initial systems that avoided dynamical decay.

Wide pre-main-sequence multiples in Taurus could be their progenitors.