> Two more things. How does one workout the solar
> day from the Sideric day and the orbital period?

Let's say y=solar day, x=sideric day, P=orbital period:


P/x - P/y = 1

so

1/y = 1/x + 1/P


> Also, was it a coincidence that 1 night on Mercury
> turns out to be one Mercurian year, given that we
> know Mercury is not completely synchronised with
> the Sun?


Huh? What do you mean a coincidence...?




Regards,
Tommi

"In this house, we obey the laws of thermodynamics!"
-Homer J. Simpson