Current affairs 2026-09-13: Hindi Diwas, Mercosur Trade, and Defense Tech

A comprehensive analysis of the day's critical current affairs for competitive exams, covering the 6th All India Rajbhasha Sammelan, India-Mercosur PTA talks, NHRC's ITEC capacity building, IAF Dronathon 2026, and major scientific breakthroughs in heat transfer.