Spacecraft collision - angular momemtum

[dopey9]

Identical spacecraft s A and B each of mass m are orbiting the Earth in different orbits...they both have the same perigee and at t=0 spacecraft A hits spacecraft B from behind

before impact speed of A was V[a]
and B was V and both a distance R from the centre of the earth

After the collision the two spacecraft stick together as a single lump of wreckage

im trying to find an expression for the angular momentum of the wreckage in terms of m, R, V[a], V...i was wondering if anyone knows what formulas i require to work out the expression...if anyone could please possibly show me how to solve this becuase I am finding it mind boggling thankz

 

[Doc Al]

Are we to assume that the collision takes place when both are at their perigee and thus are moving perpendicular to their position vectors (measured from the center of the earth)? Assuming that, answer these questions:
(1) What's the linear momentum of each spacecraft before the collision?
(2) What's the angular momentum of each spacecraft before the collision?
(3) What's conserved during the collision?