How do spaceships determine each other's mass in space?

Set in the distant future, space travel becomes prominent and cheap. I can imagine each spaceship would have a multitude array of sensors to track distance and relative position in space. Is there a good way to determine another spaceship's mass beside hailing them for specifications?

I know we can accurately know the mass of an asteroid using Newton's law of universal gravitation and probably Kepler's law too, I guess, but that's only for an orbiting object in space unlike a spaceship which usually accelerates using its own propulsion drive.

Please state the principle of measurement and I would prefer an economical solution.

posted over 5 years ago

user6760‭

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