... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . In 1966 , the Earth passed right through the trail generated in 1899 (then 2 revolutions old), causing the most spectacular meteor display of the century. In 1999, the Earth again passes near the 1899 trail (now 3 revolutions old), but further from the trail's centre than in 1966. ... A fuller explanation of these trail cross section plots is available. Go to Armagh Observatory Leonid page . ...

A completely new possibility of Fortran 90 is recursion. Note that it requires that you give a new property RESULT for the output variable in the function declaration. ... Here follows two examples, first recursive calculation of the factorial, then recursive calculations of the Fibonacci-numbers. ... The listings of the routines follow, the output variables are called FAC_RESULT and FIBO_RESULT , respectively. ... Not only functions but also subroutines can be recursive. ...