<< Back 5/22/02 The Naturalist's Corner By Don Hendershot There have been big happenings in the heavens this spring, and the show will continue for a few more weeks. Earlier this month all five of the “naked-eye” (Mercury, Venus, Mars, Jupiter and Saturn) planets were in alignment. On May 14 these planets were within 33 degrees of each other. Alignment is a little misleading because it implies the planets were in a straight line. In astronomy, alignment means two or more planets are on the same side of the sun, situated where, from earth, they can be seen close together. The last time earthlings got a good view of the naked-eye planets in alignment was 1940. The next time will be 2040. The planets were aligned in May 2000 but that grouping was hidden from earth by the sun’s glare. Presently Venus, the evening star, and Jupiter have stolen the planetary show. The two bright planets are drawing closer and closer together. Currently Venus is below Jupiter and appears to be ascending towards it. With good eyes or the aid of binoculars, one can also see the “red planet,” Mars, below and to the right of Venus. Venus will soon appear to overtake Jupiter. These two planets will be nearest on June 3. This close pairing of planets is called a conjunction. This will be a “superior” conjunction, meaning the planets are on the opposite side of the sun from us. An “inferior” conjunction occurs when the planets are between the earth and sun. Because of their orbits, the only two planets that can ever be in inferior conjunction with the earth are Mercury and Venus, the two planets closer to the sun than we are. On June 3, just after sunset, Venus and Jupiter will shine breathtakingly close in the evening sky. Venus will be just to the right and slightly above Jupiter. The two planets will appear barely a finger’s width apart (finger held at arm’s length). Of course it is the angle we are viewing them from that creates this illusion of proximity. In reality Venus will be approximately 119 million miles from Earth while Jupiter will be 561 million miles away. Orbital patterns create these alignments and conjunctions. The planets’ orbits are fixed but they revolve around the sun at different rates. The nearer a planet is to the sun the faster the orbit. One revolution for Pluto is equivalent to about 248 Earth years. On the other hand, a Mercury-year is equal to about 88 Earth days. As we spin top-like along our own gravity-defined NASCAR oval, we catch glimpses of these different planets at different points in their respective orbits. This celestial dance provides some interesting patterns in the night skies. After June 3, Jupiter and Venus will begin to drift apart. By the end of June, Jupiter will have disappeared below the horizon. The evening star, however, will still grace the night skies. (Don Hendershot can be reached at don@smokymountainnews.com)