Step 1:

The point of earth that is considered Wentworth origin is given as latitude 42 20.202 North, and longitude 71 05.692 West.

 

 

Step 2:

Withthe understanding of the given coordinates; what would be the diametricopposite coordinate?

Note:

•  LA

  TITUDE RANGE FROM 0- 90 DEGREES.
•   LONGITUDE RANGE FROM 0-180 DEGREES.

Step 3:

My first ideal move would be to find the opposite coordinateby reversing the direction: North becomes 42 20.202 S, and West becomesapproximately 109 east.  

 

Result/Conclusion:

 

The Destination that is opposite to Wentworth would be just offthe coast of Austria.