Well, the Hijri date 21 Shawwal 1410 corresponds to the Gregorian date Wednesday, 16 May 1990. This date lies in the tenth month of the Hijri year 1410 AH, which is Shawwal of 1410 AH. Both this Hijri and Gregorian date occur on the single day that is Wednesday without any doubt. The Arabic date 1410/10/21 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 16 May 1990 to its equivalent Arabic date.
The following is the conversion of the Arabic date 21 Shawwal 1410 AH to its equivalent Gregorian date.
يَوْمَ يَرَوْنَ ٱلْمَلَٰٓئِكَةَ لَا بُشْرَىٰ يَوْمَئِذٍۢ لِّلْمُجْرِمِينَ وَيَقُولُونَ حِجْرًۭا مَّحْجُورًۭا
On the day when they behold the angels, on that day there will be no good tidings for the guilty; and they will cry: A forbidding ban!
Surah Al-Furqaan(25:22)
Sahih al-Bukhari
Virtues of Prayer at Masjid Makkah and Madinah
Chapter: The Masjid Quba (the Mosque of Quba)
Narrated Nafi`:
Ibn `Umar never offered the Duha prayer except on two occasions: (1) Whenever he reached Mecca; and he always used to reach Mecca in the forenoon. He would perform Tawaf round the Ka`ba and then offer two rak`at at the rear of Maqam Ibrahim. (2) Whenever he visited Quba, for he used to visit it every Saturday. When he entered the Mosque, he disliked to leave it without offering a prayer. Ibn `Umar narrated that Allah's Messenger (ﷺ) used to visit the Mosque of Quba (sometime) walking and (sometime) riding. And he (i.e. Ibn `Umar) used to say, "I do only what my companions used to do and I don't forbid anybody to pray at any time during the day or night except that one should not intend to pray at sunrise or sunset."
Sahih al-Bukhari 1191, 1192