What is the half circle in fronk of the penelty area for?
All players, except the penalty taker must be at least 10 yards
away from the penalty spot when the penalty is taken. As the
Penalty Area extends 18 yards from the goal line, and the Penalty
Spot is 12 yards from the goal line, the distance from the Penalty
Spot to the edge of the Penalty Area can be as little as 6 Yards.
The Arc - not half circle - marks the area outside the Penalty
Area, that is within 10 yards of the Penalty Spot, and therefore
outside which players must be when the penalty is taken