In a hypothetical solar system there exist:

• a sun of radius $r_s$ and absolute visual magnitude $V$
• the Earth, with radius $r_e$ and distance from the sun of $1\,AU$
• another planet, wit radius $r_p$, albedo $a$, and distance from Earth $d$ (in units of $AU$)

Assume that the second planet is magically lit up entirely by the sun (so it does not have phases when viewed from Earth).

Now how can I compute the apparent visual magnitude of the second planet with respect to Earth?

If there are other parameters required, please tell me.

In a hypothetical solar system there exist:

• a sun of radius $r_s$ and absolute visual magnitude $V$
• the Earth, with radius $r_e$ and distance from the sun of $1\,AU$
• another planet, wit radius $r_p$, albedo $a$, distance from Earth $d_e$ (in units of $AU$), and distance from the sun $d_s$ ($AU$)

Assume that the second planet is magically lit up entirely by the sun (so it does not have phases when viewed from Earth).

Now how can I compute the apparent visual magnitude of the second planet with respect to Earth?

If there are other parameters required, please tell me.