Complex sentence: The "T'plana-hath" is a Vulcan science vessel in the 21st century, the T'plana-hath is the vessel which made first contact with Earth in the year 2063 when the Vulcans detected Earth's first warp flight.
Split into simpler sentences: The "T'plana-hath" is a Vulcan science vessel in the 21st century. The T'plana-hath is the vessel which made first contact with Earth in the year 2063 when the Vulcans detected Earth's first warp flight.