Qibla: the prayer direction and finding it

Qibla was changed from Jerusalem to Mecca in Medina: "turn your face toward the Sacred Mosque; and wherever you are, turn your faces toward it" (sura al-Baqara 144). The change was announced mid-prayer: the Prophet (may Allah's peace and blessings be upon him) turned the other way in the middle of two rak'as (al-Bukhari 393, the Bani Salama).

The effort rule (ijtihad al-wus')

• Whoever sees the Kaaba: targets it really.
• Whoever does not see it: makes his effort (astronomical computation, compass, tools); his orientation is valid even if slightly off.
• Whoever cannot determine (no tool or landmark): prays in the direction he judges most probable; his prayer is valid, and he need not redo it after information, per the majority.
• Whoever is forced (bound, immobilized sick, vehicle): prays per his situation; the heart targets qibla.
• Dar al-Ifta Misriyya (Atiyya Saqr's fatwa, p. 185): facing the qibla is a validity condition of the obligatory (sura al-Baqara 144), resident and traveling alike; the traveler's voluntary prayer follows the heading (al-Bukhari and Muslim, from 'Amir ibn Rabi'a); the train, ship or plane passenger able to move faces the qibla and follows it wherever it turns; if he cannot, he prays per what he can and the impossible gestures fall away; the car occupant alights to pray if the stop is safe.

Modern determination

Stars are the sky's safety; when they vanish, what was promised comes. And I am the safety of my Companions.Muslim 101

Muslims navigated by stars from the start: astronomical qibla determination (great circle to the Kaaba, exact angle per city) completes that science; current applications compute it to the degree. The historical divergence (great circle vs rhumb line) is settled by experts' practical consensus: the great circle.

Ibn Baz (Fatawa Nur ala ad-Darb, pp. 77-80) applies the rule mid-flight: the obligatory follows the qibla turning with the aircraft, standing if possible; Dar al-Ifta Misriyya (Atiyya Saqr's fatwa, p. 484) notes that navigators know it by approximation or compass: effort suffices, estimation error is pardoned.

Pardoned errors

• Estimation error without tools: pardoned by consensus.
• Discovering the error during prayer: turn and continue (reported of the Prophet praying toward Jerusalem then turned, al-Bukhari 393).
• After salam, discovering a gross error: redo it per scholars' caution, except invincible ignorance.

Practical note

Fix your room's qibla once for all (wall, discreet sticker) and verify with two independent sources: direction is not guessed, it is computed; effort suffices, perfection is not asked.