The calculated distance (air line) between Dimona and Rishon LeTsiyyon is approximately 64 miles respectively 103 kilometers.
By car or train, the actual journey to Rishon LeTsiyyon is certainly longer, as only the direct route (as the crow flies) between Dimona and Rishon LeTsiyyon has been calculated here.
Air line (approximately)
103 kilometers
55 nautical miles