It may sound like I am contradicting what I have said before about the May 5, 2000 event in previous questions, but astronomers do not use the vague term 'alignment' to describe planetary positions in the sky. If people ask me whether the planets will form a straight line, I answer by looking at an ephemeris that gives the locations of the planets in the solar system relative to the Sun and Earth. I then assume the question is whether the planets in their various orbits trace a straight line as seen from either the Sun or the Earth. This is not the case with May 5, 2000. I then assume that the question was whether the planets, from the Earth, will appear in a straight line in the sky in an unusual tight formation.
If you ask whether a conjunction will occur of the planets on May 5, 2000 the answer is no, because conjunctions are close passes of two planets to each other in the sky. There will be several of these in the year 2000, but only the Mercury - Uranus conjunction on May 1, 2000 is a true conjunction. Sometimes astronomers speak of 'Grand Conjunctions' but it is a subjective difference between a Grand Conjunction involving planets over 10 - 20 degrees separation, and one involving planets separated by, say 5 times that distance. I will, however, follow the lead of others and acknowledge that the May 5, 2000 event is a bonifide Grand Conjunction. You may even call it an alignment, although I cringe at the term.
Copyright 1997 Dr. Sten Odenwald
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