Answer
Wa `alaykum As-Salamu wa Rahmatullahi wa Barakatuh.
In the Name of Allah, Most Gracious, Most Merciful.
All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.
In this fatwa:
The Prayer the Prophet (peace and blessings be upon him) performed on that night, it might have been composed of two rak`ahs, as the Prayer before the Night Journey was two rak`ahs at the beginning of the day and two rak`ahs at its end, or it might have been voluntary Prayer.
In his response to your question, Sheikh `Atiyyah Saqr, former head of Al-Azhar Fatwa Committee, states:
Among the miracles the Prophet (peace and blessings be upon him) saw during the Night Journey was that demonstrated in the hadith reported by Al-Bazzar, At-Tabarani and Al-Bayhaqi, and which the latter authenticated in his book Dala’il An-Nubuwwah.
This hadith, narrated by Shaddad ibn Aws (may Allah be pleased with him), states that during the Prophet’s Night Journey, he passed by a land of date palms, whereupon, Jibreel (Angel Gabriel) ordered him to dismount from Al-Buraq to perform Prayer. After he did, Jibreel told him that the place in which he performed prayer was Yathrib or Tibah (that is, Madinah) to which he would immigrate.
Then, Jibreel ordered him to perform Prayer when he passed by Madyan at Moses’s tree under which, according to some scholars, Moses had sat after watering the sheep for the two women and before meeting their father. When the Prophet (peace and blessings be upon him) and Jibreel passed by Mount Sinai, where Allah had spoken to Moses, Jibreel ordered the Prophet (peace and blessings be upon him) to perform Prayer. He also prayed when he passed by Bethlehem where Jesus, son of Mary, had been born.
According to Al-Bayhaqi, the above events were reported from authentic chains of narrations. I have not encountered any other authentic hadiths about the Prophet’s performance of Prayer during his Night Journey and before ascension in other than the above-mentioned places.
Some of the narrations describing what the Prophet (peace and blessings be upon him) saw during that night are reported through authentic chains of narrations while others are not.
One of these unauthenticated narrations was reported by At-Tabarani, Al-Bazzar, Al-Bayhaqi, Ibn Jarir and Abu Ya`la.
According to this narration, the Prophet (peace and blessings be upon him) passed by a valley in which he found a good smell like that of musk and heard a sound. Jibreel told him that this was the sound of Paradise giving the glad tidings to its dwellers.
Then, according to the same narration, he (peace and blessings be upon him) passed by a valley in which he heard an abominable voice and smelled a rotten odor. Jibreel told him it was the sound of Hellfire. However, this narration was not regarded as authentic, good, or even weak.
In any case, we are not obliged to believe in such narrations, even if they are plausible, as there are no plain exclusive texts to prove them. The Night Journey is strange in itself, and has its own excellence and honor. It does not need any additions to increase its honor further than the authentic hadiths.
In this regard, I would like to reiterate the gravity of attributing any words to the Prophet (peace and blessings be upon him) which he did not say. He (peace and blessings be upon him) said, “He who intentionally attributes something false to me, let him take his abode in Hellfire.” (Al-Bukhari and Muslim)
As for the Prayer the Prophet (peace and blessings be upon him) performed on that night, it might have been composed of two rak`ahs, as the Prayer before the Night Journey was two rak`ahs at the beginning of the day and two rak`ahs at its end, or it might have been voluntary Prayer.
Almighty Allah knows best.