The calculated distance (air line) between Det Udom and Ubon Ratchathani is approximately 28 miles respectively 44 kilometers.
By car or train, the actual journey to Ubon Ratchathani is certainly longer, as only the direct route (as the crow flies) between Det Udom and Ubon Ratchathani has been calculated here.
Air line (approximately)
44 kilometers
24 nautical miles