Astronomers have clever ways to weigh celestial objects without using a traditional scale. Gravity and mass are closely related, with weight changing due to the strength of gravitational pull. For instance, stepping on a scale on Earth may show a different weight compared to Jupiter, but your mass remains constant.
One method astronomers use is observing the time it takes nearby bodies to orbit a central object. By knowing the distance between them, the mass of the central body can be calculated. Binary stars also offer insight, as astronomers can observe their orbits to determine their combined mass. Galaxies are a bit trickier, but by studying their rotation speed, researchers can estimate their mass.
Another technique involves using luminosity to estimate mass. Typically, the brightness of a star or galaxy is proportional to its mass. By understanding this relationship and using computer simulations, scientists can infer the mass of celestial objects based on their luminosity, temperature, and composition. With these tricks, scientists can shed light on the weight of celestial bodies without traditional scales.
