Well, the Hijri date 16 Rabi Al Thani 1400 corresponds to the Gregorian date Monday, 3 March 1980. This date lies in the fourth month of the Hijri year 1400 AH, which is Rabi Al-Thani of 1400 AH. Both this Hijri and Gregorian date occur on the single day that is Monday without any doubt. The Arabic date 1400/04/16 is calculated using the Umm Al-Qura calendar and the sighting of the moon. One thing to remember is that this Arabic date may occur on different Gregorian date depending upon the region and country and obviously the moon.
If you are still not sure about the date then you can use our Arabic date converter.
The following is the conversion of the Gregorian date 3 March 1980 to its equivalent Arabic date.
The following is the conversion of the Arabic date 16 Rabi Al Thani 1400 AH to its equivalent Gregorian date.
وَثَمُودَ ٱلَّذِينَ جَابُوا۟ ٱلصَّخْرَ بِٱلْوَادِ
And with (the tribe of) Thamud, who clove the rocks in the valley;
Surah Al-Fajr(89:9)