What is the ruling on masturbating during the day in Ramadan, and at night with ghusl (ritual bath) shortly before the Maghrib call to prayer, and is qadaa' (making up for the fast) obligatory?

Repentance to Allah is obligatory for intentional, forbidden masturbation. If masturbation occurs during the daytime in Ramadan and semen is discharged, that day must be made up. As for masturbation at night, making up the day is not necessary, but one incurs sin for missing prayers before performing ghusl, and according to the majority of scholars, these prayers must be made up.