Perturbation
Thisbe has been perturbed by asteroid 7 Iris and in 2001 Michalak estimated it to have a mass of 1.5×1019 kg. But Iris is strongly perturbed by many minor planets such as 10 Hygiea and 15 Eunomia.
In 2008, Baer estimated Thisbe to have a mass of 1.05×1019 kg. In 2011 Baer revised this to 1.83×1019 kg with an uncertainty of 1.09×1018 kg.
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