The calculated distance (air line) between Poninka and Starokostyantyniv is approximately 33 miles respectively 53 kilometers.
By car or train, the actual journey to Starokostyantyniv is certainly longer, as only the direct route (as the crow flies) between Poninka and Starokostyantyniv has been calculated here.
Air line (approximately)
53 kilometers
28 nautical miles