What is the iddah (waiting period) for a widowed woman who has undergone a hysterectomy and is elderly, and is it permissible for her to travel to visit her son in a foreign country during her iddah?

A widow must observe the iddah (waiting period), even if she is certain she is not pregnant, because Allah the Almighty says: "And those of you who die and leave wives behind them, they (the wives) shall wait (as regards their marriage) for four months and ten days." Traveling during the iddah is not permissible, based on Allah the Almighty’s statement: "Do not turn them out of their houses, nor shall they (themselves) leave," and what An-Nasa’i narrated from Furay’ah bint Malik. As for traveling after the iddah, there is no objection to it, provided a mahram (unmarriageable kinsman) is present.