> > Newton's laws of motion - not laws.
> >
>I think they are, for reasonable values of legality, in that they
>predict where Mars will be when an astronaut reaches it, given when he
>leaves Earth, and where Earth will be and when to leave Mars in order to
>reach it.  That they are an approximation because the theory they are
>based on is incompletely accurate is another matter.

We seem to be back to semantics.

http://wilstar.com/theories.htm

"Scientific Law: This is a statement of fact meant to explain, in 
concise terms, an action or set of actions. It is generally accepted 
to be true and universal, and can sometimes be expressed in terms of 
a single mathematical equation. Scientific laws are similar to 
mathematical postulates. They don't really need any complex external 
proofs; they are accepted at face value based upon the fact that they 
have always been observed to be true.

Specifically, scientific laws must be simple, true, universal, and 
absolute. They represent the cornerstone of scientific discovery, 
because ***if a law ever did not apply, then all science based upon 
that law would collapse***."

Quite specifically Newton's laws do not _always_ apply, and they are 
not universal or absolute (hence, in some senses, not true).  They 
are good approximations useful for most (but not all) things we 
need.  Wikipedia seems to try to square this circle, using a very 
similar definition to the one above which requires that laws be 
absolute and universal, while immediately going on to point out how 
many laws are not laws but approximations.

Not only do scientists seem to be abusing their own definitions, but 
since most people who learn a little science do not understand the 
niceties of the terminology it would be far more honest for science 
to use terminology that is readily understood by all.

I think some understand that, as evidenced by the recent extensive 
debate on the definition of a planet.

Julian
PS Whether using Newton's laws or any other method just how far ahead 
do you believe we can currently compute the movements of the planets?