1. Move the decimal point: Start with the decimal point at the end of the number (238,855.). Move it to the left until you have a number between 1 and 10. In this case, we move it five places to the left, giving us 2.38855.

2. Exponent: Since we moved the decimal point five places to the left, the exponent for the base 10 is 5.

3. Scientific notation: Combining the steps above, we get: 2.38855 x 10⁵ miles.

Therefore, 238,855 miles in scientific notation is 2.38855 x 10⁵ miles.