What is the authenticity of the Hadith of the Ibex and its scientific interpretation?

The Hadith of the Ibexes (al-Aw'al), narrated by Al-Abbas ibn Abd al-Muttalib from the Prophet, peace and blessings be upon him, describes the layers of the heavens and what is above them, including a sea and ibexes (or mountain goats) carrying the Throne, above which is Allah the Almighty. Scholars have differed regarding the authenticity of this hadith. Some have deemed it good (hasan) or authentic (sahih), such as Ibn Khuzaymah, Al-Hakim, and Ibn Taymiyyah. Others have deemed it weak (da'if), such as Al-Bazzar, Ibn 'Adi, and Al-Albani. The reasons for its weakening are attributed to the uniqueness of Simak ibn Harb in its narration, the anonymity of Abdullah ibn 'Umayrah, and the presence of a discontinuity between him and Al-Ahnaf ibn Qays. Despite the weakness of this hadith, the evidence for Allah's exaltedness (uluw) and His establishment (istiwa') upon the Throne is abundant in the Qur'an and authentic Sunnah.