An unmanned spacecraft travels to Mars. Mars has a lower strength of gravity than Earth. Where is the spacecraft's weight the greatest?

This screenshot should explain it all. On earth, the spaceship would weigh the most because in space there is no force and Mars has a lower strength of gravity than earth. Therefore Earth is where you would weigh the heaviest, next to Mars then space.

Mars has a lower strength of gravity than Earth - 62% lower.

The connection between the weight and the force is the following: Weight is the force caused by gravity. The weight of an object is the gravitational force between the object and the Earth. So,

a person who weighs 100 kg on Earth would weigh only 38 kg on Mars.

According to this, the unnamed spacecraft which travels to Mars, will have the greatest weight on the Earth.