The Size of the Solar System

Finally, as a take-home exercise, we need to change our scale to let the 40 AU of the solar system equal the 455 miles from Las Cruces to the Colorado border.

Here is a detailed map of the state of New Mexico, with mile markers more clearly marked than in your lab.

On this new scale, if we want to convert AUs in the solar system to miles on I-25, we multiply by 455 miles, then divide by 40 AU.

For planetary sizes on this scale, let's use 1 AU to find our scale factor again. 1 AU, which is also 150 million km - is equivalent to 11.4 miles on this scale. So, if we want to convert km sizes of planets to feet sizes on I-25, we multiply by 11.4 miles, multiply again by 5,280 feet per mile, then divide by 150 million km.