The planetary data table below provides direct comparisons between the Earth and other objects in the solar system. Values are scaled to absolute values for Earth: sidereal period = 365.25 days, volume = 1.08 × 1012 km3, mass = 5.976 × 1024 kg, surface gravity = 9.80 m s–2, and rotational period = 23.93 hr (sidereal day). For example, the surface gravity of Mars is 0.38 × 9.80 = 3.72 m s–2.
* Rotational period at the equator of the Sun.
† Rotation is retrograde, opposite to rotation of Earth.
* Average distance from the Earth.
The equatorial diameter of the Earth, 12,756 kilometers (7654 miles), is defined to be one unit in this scale.
Solar system dimensions can be illustrated on whatever scale is chosen to represent Earth. If Earth were represented by a grain of sand 0.2 millimeters (0.05 inches) in diameter, the Sun would then be 0.2 × 109 = 21.8 millimeters (0.86 inches) in diameter, located 0.2 × 11,700 = 2340 millimeters (92 inches) from Earth, and Pluto would be 0.2 × 463,000 = 92,600 millimeters (304 feet) from the Sun. Similar comparisons can be made with a standard 30.5-cm (12-inch)-diameter globe of Earth, with a corresponding increase in the relevant distances and sizes for the other planets.
Back to introduction | Back to slide index
Back to top
to LPI Slide Sets | Back
to LPI Home page