How about "River Trans" ?
Trans river would be trans flumen means: To cross a river or
German: über den Fluss Translates back to English as: Over the river
Polish:po drugiej stronie rzeki Translates back to English as: on the other side of the river
In Latin the meaning of the name Astra is: From astralis meaning of the stars, derived from the Greek astron meaning star.
In Greek the meaning of the name Astra is: Star
In Norse the meaning of the name Astra is: Divine strength