Mercury has a gravitational pull equal to 38 percent of that of Earth due to its smaller size. An object weighing 100 pounds on Earth weighs only 38 pounds on Mercury.
Comparatively, the same object would weigh only 6.7 pounds on Pluto, 12.64 pounds on Jupiter's moon Callisto, 16.7 pounds on Earth's moon, 37.7 pounds on Mars and 236.4 pounds on Jupiter. Because of the size and low gravity on Mercury, it has almost no atmosphere and has a temperature range from -346 to 950 degrees Fahrenheit. Mercury circles the sun in only 88 days, and its surface resembles that of Earth's moon. With a diameter of only 3,000 miles and only 5.5 percent of the volume of Earth, Mercury is the smallest planet in the solar system.