Engineer's Day in Iran
Engineer's Day in Iran is held on February 23. This day is celebrated to respect Nasir al-Din al-Tusi, Iranian scientist. This event in the third decade of the month February is annual. 
Help us
Help us 
Nasir al-Din al-Tusi left behind a great legacy as well. Tusi is widely regarded as one of the greatest scientists of medieval Islam, since he is often considered the creator of trigonometry as a mathematical discipline in its own right.
In mathematics, al-Tusi pioneered spherical trigonometry and treated trigonometry as a new mathematical discipline. He developed six fundamental formulas for the solution of spherical right-angled triangles. He wrote on binomial coefficients, which Blaise Pascal later introduced.
Similar holidays and events, festivals and interesting facts
Father's Day in some Islamic countries on January 13 (Iran, Kuwait, Bahrain, Iraq, Oman, Qatar, Egypt, Yemen, Syria, Lebanon, Somalia, Sudan, Mauritania is celebrated on the 13th day of the month of Rajab);
Iran Engineer's Day on February 24
Baloch Culture Day on March 2 (Balochistan);
Tree Planting Day in Iran on March 5
Iranian New Year on March 21
Iranian Islamic Republic Day on April 1
Sizdah Be-dar in Iran on April 2 (celebrated on the 13th day after vernal equinox)