In the Table below the masses of some asteroids which were determined during the last years are listed. ... The listed values were determined from observations of many test bodies by the weighted least square fit for one perturbing mass and corrections to the orbit elements of all used test bodies. ... based on the observations of 98 asteroids (including 50278) with the values of standard error of mass determination less than 3.0 10 -11 M Sun . ... Mass . ... 3) Mass 121 : 0.74 x 10 -11 M Sun ; . ...