What is the meter in the first line of Donne's "Go and Catch a Falling Star"?

The meter of the first line of John Donne's "Go and Catch a Falling Star" is similar to many of the other lines, but because of the truncation of the line, the meter can be somewhat hard to discern. In order for this to make sense, it will be useful to explain the composition of the first line. The line itself has four feet, with each foot consisting of two syllables, although the final foot is truncated. There are two syllables in each of the first three feet and one in the final foot. Each foot is made up of a trochee, which is one stressed syllable followed by one unstressed syllable. The truncation of the final foot occurs on the unstressed syllable. The rules of poetry allow for this truncation while still maintaining the meter. Because there are four feet in the line (tetrameter) and two syllables—one stressed, followed by one unstressed (trochee)—per foot, the meter of the first line is trochaic tetrameter.