I am going to Japan from USA. I will leave on Saturday 10 am and will arrive to Japan on Sunday at 2. 20 pm. How can I define the prayer times when I am in the plane and the difference in timing will be different.

Praise be to Allah, the Lord of the Worlds; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions. The validity of the prayer as far - as timing is concerned - is achieved when praying after the entering of the fixed time. So, whenever, the fixed time of the prayer enters, the person can pray. On the other hand, as long as the fixed time of the prayer has not entered, the person should not pray as such a prayer would not suffice him/her. One could, in these days, rely on what the contemporary diaries that contain prayer times. This differs from one country to another depending on their locations on earth. However, the person traveling in planes cannot determine, for sure, the place where he is, while the plane is still in the air. So, he/she must make sure that the time of the prayer has entered by using the natural signs. For example, Maghrib is recognized by sunset, Isha by the disappearance of the red twilight and Fajr is recognized by dawn which is the white colour that covers the horizon. As for Zuhr and Asr, the person does his/her best to determine their times. He/she can ask some of the crew or staff of the plane who may have devices that tell the time accurately wherever the plane is. Now, if the person does his/her best to define the time and prays, he does not have to make up that prayer unless he becomes certain that he/she has prayed it before its fixed time, then he/she should make it up. Other wise, Allah Says (interpretation of meaning): {"Allah burdens not a person beyond his scope. …}[2:286]. Allah knows best.