When dealing with distances in space, I’ve found that I don’t have a good conceptual framework for understanding these large distances. I’ve found reframing these distances in terms of “Car Years” (and “Car Days”) to be helpful.
What is a Car Year?
A car year (cy
) is the distance covered by traveling at 60 miles per hour
(approximate highway speed) nonstop for one year (i.e. 525,960 miles). Along the same thinking, a car day is the distance covered by traveling at 60 miles per hour for one day (i.e. 1440 miles).
Distances in Car Years (or Days)
 1.5 car days across the U.S. (NY to CA)
 14 car days around the Earth
 140 car days to the Moon
 150 car years to the Sun

10 million car years = one light year

1 light second = 100 car days
Do We Really Need Another Unit of Distance
Yes, apparently I do.
Advantages of the Car Year
When dealing with large measurements, I’ve found my brain fails in two different ways.
 The number is too big.
 The units are unfamiliar.
Number Size
Because part of our unit is a time (e.g. year
, or day
). We can easily convert between units to keep the number “manageable” for my brain.
Light years/minutes/seconds have this same advantage but fail in the second way (units).
Familiar Units
As mentioned, light years/minutes/seconds has the same advantage of controlling number size based on converting between units of time (which I have a strong conceptual understanding and “feel” for). Unfortunately, I don’t have a good “feel” for the speed of light. With car years/minutes/seconds, I have a strong understanding and “feel” for a car’s highway speed.
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