Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
tabarani:8730 – Muḥammad b. al-Naḍr al-Azdī > Muʿāwiyah b. ʿAmr > Zāʾidah > Manṣūr b. al-Muʿtamir > Ibrāhīm > al-Aswad

[Machine] I saw Abdullah and Omar, or one of them, prostrate when the heavens split.  

الطبراني:٨٧٣٠ – حَدَّثَنَا مُحَمَّدُ بْنُ النَّضْرِ الْأَزْدِيُّ ثنا مُعَاوِيَةُ بْنُ عَمْرٍو ثنا زَائِدَةُ عَنْ مَنْصُورِ بْنِ الْمُعْتَمِرِ عَنْ إِبْرَاهِيمَ عَنِ الْأَسْوَدِ قَالَ

رَأَيْتُ عَبْدَ اللهِ وَعُمَرَ أَوْ أَحَدَهُمَا يَسْجُدُ فِي إِذَا السَّمَاءُ انْشَقَّتْ  

See similar narrations below:

Collected by Ṭabarānī
tabarani:8728 – Muḥammad b. al-Naḍr al-Azdī > Muʿāwiyah b. ʿAmr > Zāʾidah > Layth b. Abū Sulaym > ʿAbd al-Raḥman b. al-Aswad from his father

[Machine] Abdullah used to prostrate when the sky split open.  

الطبراني:٨٧٢٨ – حَدَّثَنَا مُحَمَّدُ بْنُ النَّضْرِ الْأَزْدِيُّ ثنا مُعَاوِيَةُ بْنُ عَمْرٍو ثنا زَائِدَةُ عَنْ لَيْثِ بْنِ أَبِي سُلَيْمٍ عَنْ عَبْدِ الرَّحْمَنِ بْنِ الْأَسْوَدِ عَنْ أَبِيهِ قَالَ

كَانَ عَبْدُ اللهِ يَسْجُدُ فِي إِذَا السَّمَاءُ انْشَقَّتْ