Phase Resolved Observational Study and Imaging Analysis of the September 2025 Total Lunar Eclipse

Abstract

This paper gives observations and analysis of the 2025 September total lunar eclipse as witnessed from Thiruvananthapuram, Kerala, India. The six major phases of the eclipse were captured with high-resolution images using a 130 mm Newtonian reflector telescope, including the complete Moon prior to the eclipse, penumbral onset, partial umbral stages, and totality. The duration of each phase was meticulously noted, giving an accurate timeline account of the event. Relative brightness of the Moon was recorded at every phase, decreasing from 100% when full to 10–15% at totality, indicative of the shadow effect of the Earth and atmospheric scattering of sunlight. Ambient temperature was also recorded, decreasing from 28.0°C to  at totality, showing minimal environmental impact related to the eclipse. The observations show the definite trend of lunar shadowing, progression of red "Blood Moon" coloration, and relation between qualitative observation, quantitative brightness, and change in temperature. The study indicates the necessity of methodical observation and consolidation of various measurements to interpret lunar eclipses and their subtle impact on local conditions.