1 AU (astronomical unit) is about the average Earth-Sun distance: 150 million km.
What to notice
Average distance from the Sun
Approximate values in AU. Use these for your worksheet.
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A scale tells what a measurement on a model represents in real life. For example, 1 cm could represent 1 AU. At that scale, 2 cm represents 2 AU. A scale model uses the same scale for the measurements it compares.
Sizes: Planet diameters are compared at one scale. Spacing is changed, and rings are omitted. The Include the Sun checkbox lets you switch between a view with our star and a closer view of just the planets. The scale changes, but the relative diameters stay the same.
Distances: Positions use average Sun-to-planet distances, measured from center to center. Hollow circles are enlarged location markers. Planets move around the Sun; this straight line is not their actual arrangement. Neptune is the farthest planet, but the solar system extends far beyond it.
Data use NASA's approximate equatorial planet diameters and average orbital distances. The Sun's diameter is 1,391,400 km. Displayed comparisons are rounded; drawings use the underlying kilometer values. Colors are illustrative. Moons, dwarf planets, asteroids, and comets are not shown.
NASA: Planetary Fact Sheet · NASA: Sun Fact Sheet · NASA: Cosmic Distances · NASA: Beyond Neptune