DO YOU STILL have the Spam and bottled water you put away to survive the Y2K bug? Hold on to it or buy more soon. Get enough food to last ten years, enough water for six months. Maybe even build an underground shelter.

Or be reasonable. Some companies dealing in survivalist supplies are cashing in on an upcoming astronomical event: the Great Conjunction or Planetary Alignment of May 5, 2000. On that day, seven planets--Moon, Sun, Mercury, Venus, Mars, Jupiter, and Saturn (in astrological terms, the Sun and Moon are considered planets)--will be aligned along their orbital paths. Some so-called experts are insisting that the combined gravitational pull of these planets will destabilize Earth and cause widespread catastrophe.

Nonsense. We're making our own prediction for May 5: It will be even less eventful than Y2K.

The fearmongers among us include some of these prognostications in their warnings: Polar ice caps will move; sea levels will rise 100 to 300 feet; huge tidal waves will occur; winds will reach 500 to 2,000 miles per hour; earthquakes may measure 13 on the Richter scale; both coasts of the United States may be underwater; magnetic fields will shift; and Earth's crust will move.

Let's return to scientific reality. Yes, seven "planets" will align pretty well on May 5, to within 26 degrees of each other. That's about as exciting as it will get. You won't even be able to see these planets lined up because the Sun will be in your way. It will be a big yawner, and here's why.

First, the tidal forces acting on our planet are, for all practical purposes, caused solely by the Sun and Moon. Even Venus, the nearest planet to ours, exerts only a small, calculable (but not noticeable) tidal force. True, at the new Moon and full Moon, the tidal forces of the Moon and Sun are added together, causing Earth's tides to be higher than average. On May 5, Earth will be subject to a tidal force similar to that which occurs at every new Moon, but the additional force caused by Mercury, Venus, Mars, Jupiter, and Saturn will be negligible. Since all the planets are on the far side of the Sun for this event, their combined gravitational pull will be even weaker than usual. There will be no direct or indirect effect on our weather or on sunspots, which can effect the weather.

Second, doomsayers are intrigued by the seemingly rare alignment. Some have even said that it has been 6,000 years since such a thing happened last. Not true. Although Great Conjunctions have no discernible pattern, we had one in 1962 and will have them again in 2040 and 2100. After that, there won't be another one for 300 years. In 1982, all nine planets aligned (but not the Sun and Moon), and, well, here we are, still alive.

"Alignments" of various planets occur relatively often. Sometimes planets are aligned more tightly than they will be on May 5, when they will have a span of 26 degrees in an arc. An alignment with a span of 50 to 60 degrees can happen as often as every 15 to 20 years. A span closer to this year's, say 30 degrees, has occurred 12 times in the past 1,000 years. Even tighter alignments occurred in 1186, when the planets were within 12 degrees of each other, and in 1962, when the span was 16 degrees.

The regrettable side of almost all Great Conjunctions is that they are not observable with the naked eye because everything happens in the neighborhood of the Sun. The 1962 Great Conjunction coincided with a total solar eclipse, which made viewing Mercury, Venus, Mars, Jupiter, and Saturn possible for a brief period of time from a small stretch of Earth where the eclipse's shadow hit.

Finally, Great Conjunctions are not of any special interest to the folks at NASA, although NASA often does use planetary pull to give satellites an additional push and thus save fuel.