The formula to convert Fahrenheit to Celsius is:

C = (F - 32) * 5/9

where C is the temperature in Celsius and F is the temperature in Fahrenheit.

So, to convert -52 degrees Fahrenheit to Celsius, we have:

C = (-52 - 32) * 5/9

C = (-84) * 5/9

C = -40°C

Therefore, -52 degrees Fahrenheit is equal to -40 degrees Celsius.