USAAAO — 2024 First Round

Samvit observes a binary star system of masses M1 and M2. Unfortunately, the star with mass M2 is too dim for him to observe it, leading to the snapshot shown below. What could Samvit hypothesize to be the position and mass of the other star at this instant that would be consistent with the laws of physics and the orbit snapshot that he sees? To be clear, he has no knowledge of the value of M2 or the period of the binary system.