Fixes runtime error when particle accelerators hit the edge of a planetary map #48550

Job	Run time
Compile All Maps	1m 13s
Lints	1m 42s
Find Maps to Test	16s
Lint with OpenDream	48s
Compile and Run Tests (donutstation)	5m 7s
Compile and Run Tests (icemeta)	7m 45s
Compile and Run Tests (gaxstation)	4m 34s
Compile and Run Tests (manateestation)	5m 23s
Compile and Run Tests (ministation)	4m 51s
Compile and Run Tests (multiz_debug)	4m 35s
Compile and Run Tests (runtimestation)	4m 19s
Compile and Run Tests (yogstation)	6m 8s
Final Map Test	1s
	46m 42s

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