When the planets in our Solar System are in a line on 5 May 2000, will there be any reason for concern on Earth?
Asked by: Matt
This is a good question because a lot of people think that when all of the planets are lined up
something special is bound to happen. I suppose this is because it is an unusual event. But we
must remember that it is unusual only because it does not happen often and it does not happen often
only because of the various velocities with which the planets orbit the sun. The planets orbit the
sun at various velocities simply because they are at various distances from the sun. So, it is
only a matter of time that all of the planets will be in a straight line from the perspective of
There is another reason why some people think that this event could bring us problems. Some people
think that the gravitational pull of all of the planets will cause something to happen here on
earth. What you have to remember is that this planetary line up has occurred before with no ill
effects on earth; not even the tides! The gravitational pull of all of the planets combined on
earth is almost nothing when compared to the gravitational pull of the sun on earth. That is why
we orbit the sun and not the other planets!
There may be a third reason why some people are concerned about this event. They may think that
there is some astrological significance to this event. Some would say that the gravitational
effects of the planets could have an effect on us. Perhaps there can be an effect on our blood
flow or on how our neurons interact or on some other magnetic/biological system of which modern
medicine knows little or nothing. But, in this case the gravitational pull of the earth is so
very much greater than all of the planets combined that their addition is like adding a penny to a
The only thing I would worry about with regard to this rarest of events is that I might miss it!
It will never happen again in our lifetime. My biggest concern is that there will be clouds
blocking my view!
I hope this helps calm any fears you might have had!
Answered by: Tom Young, M.S., Science Teacher, Whitehouse High School, Texas
'Physics is mathematical not because we know so much about the physical world, but because we know so little; it is only its mathematical properties that we can discover.'