Well, the Hijri date 19 Shaban 1409 corresponds to the Gregorian date Sunday, 26 March 1989. This date lies in the eighth month of the Hijri year 1409 AH, which is Shaban of 1409 AH. Both this Hijri and Gregorian date occur on the single day that is Sunday without any doubt. The Arabic date 1409/08/19 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 26 March 1989 to its equivalent Arabic date.
The following is the conversion of the Arabic date 19 Shaban 1409 AH to its equivalent Gregorian date.
يَسْـَٔلُكَ أَهْلُ ٱلْكِتَٰبِ أَن تُنَزِّلَ عَلَيْهِمْ كِتَٰبًۭا مِّنَ ٱلسَّمَآءِ ۚ فَقَدْ سَأَلُوا۟ مُوسَىٰٓ أَكْبَرَ مِن ذَٰلِكَ فَقَالُوٓا۟ أَرِنَا ٱللَّهَ جَهْرَةًۭ فَأَخَذَتْهُمُ ٱلصَّٰعِقَةُ بِظُلْمِهِمْ ۚ ثُمَّ ٱتَّخَذُوا۟ ٱلْعِجْلَ مِنۢ بَعْدِ مَا جَآءَتْهُمُ ٱلْبَيِّنَٰتُ فَعَفَوْنَا عَن ذَٰلِكَ ۚ وَءَاتَيْنَا مُوسَىٰ سُلْطَٰنًۭا مُّبِينًۭا
The people of the Scripture ask of thee that thou shouldst cause an (actual) Book to descend upon them from heaven. They asked a greater thing of Moses aforetime, for they said: Show us Allah plainly. The storm of lightning seized them for their wickedness. Then (even) after that) they chose the calf (for worship) after clear proofs (of Allah's Sovereignty) had come unto them. And We forgave them that! And We bestowed on Moses evident authority.
Surah An-Nisaa(4:153)