The weight of an object on Mercury is approximately 38% of its weight on Earth. This is because Mercury is a much smaller planet than Earth, with only about 5.5% of Earth's mass. The force of gravity is proportional to the mass of the planet, so objects weigh less on Mercury than they do on Earth.

To calculate the weight of an object on Mercury, you can use the following formula:

Weight on Mercury = (Weight on Earth) × (Mass of Mercury / Mass of Earth)

For example, if an object weighs 100 pounds on Earth, its weight on Mercury would be:

Weight on Mercury = 100 pounds × (0.055 / 1) = 5.5 pounds

Therefore, the object would weigh only 5.5 pounds on Mercury.