IT IS MUSTAḤABB, when waking up at night and going out of one’s house, to look at the sky and recite the last verses of Sūrah Āl ‘Imrān, from “Verily in the Creation of the heavens and the earth” [1].to the end of the sūrah.
Inna fī khalqi-s-samāwāti wa-l-arḍ. . .
It is recorded in the Ṣaḥīḥs of al-Bukhārī and Muslim that the Messenger of Allah 
used to do this. His looking at the sky is mentioned in the Ṣaḥīḥ of al-Bukhārī, not in that of Muslim. [2].
used to do this. His looking at the sky is mentioned in the Ṣaḥīḥ of al-Bukhārī, not in that of Muslim. [2].It is recorded in the same two Ṣaḥīḥs that Ibn ‘Abbās 
reported that when the Messenger of Allah got up in the night to perform the Tahajjud ṣalāh he would say: “O Allah, to You belongs all praise. You are the Everlasting Sustainer of the heavens and the earth and all who are in them. To You belongs all praise; You are the King of the heavens and the earth and all who are in them. To You belongs all praise; You are the Light of the heavens and the earth and all who are in them. To You belongs all praise; You are the Truth, Your promise is true, meeting You is true, Your Word is true, Paradise is true, Hell is true, Muḥammad is true and the Hour is true. O Allah, to You I submit and in You I believe and on You I depend and to You I turn in repentance, and by You I contend and to You I refer judgment. Forgive me my past and future sins, those which I have done in secret and those which I have done openly. You are the One Who brings near and You are the One Who puts far away. There is no god but You.” Some of the narrators add: “And there is no power or strength except by Allah.” [3].
reported that when the Messenger of Allah got up in the night to perform the Tahajjud ṣalāh he would say: “O Allah, to You belongs all praise. You are the Everlasting Sustainer of the heavens and the earth and all who are in them. To You belongs all praise; You are the King of the heavens and the earth and all who are in them. To You belongs all praise; You are the Light of the heavens and the earth and all who are in them. To You belongs all praise; You are the Truth, Your promise is true, meeting You is true, Your Word is true, Paradise is true, Hell is true, Muḥammad is true and the Hour is true. O Allah, to You I submit and in You I believe and on You I depend and to You I turn in repentance, and by You I contend and to You I refer judgment. Forgive me my past and future sins, those which I have done in secret and those which I have done openly. You are the One Who brings near and You are the One Who puts far away. There is no god but You.” Some of the narrators add: “And there is no power or strength except by Allah.” [3].
References
[1] Qur’ān 3:190–200.
[2] Al-Bukhārī (4569) and Muslim (763).
[3] Al-Bukhārī (1120) and Muslim (769).