UMM4J solar cells are evaluated under different LILT conditions. The efficiency findings near Earth’s orbit (1 sun, 300 K), Jupiter (0.032 sun, 123 K), and Saturn (0.01 sun, 100 K) are 26.54%, 29.68%, and 28.27%. According to single diode model, Jsc is linear with light intensity (I), while Voc is linear with the natural logarithm of light intensity (ln(I)). Voc shows a linear relationship with temperature within the range of 150K to 300K, with a temperature coefficient of ∽ ‐7. 7 mV/K. However, Voc displays a sublinear relationship with temperature below 150K.This article is protected by copyright. All rights reserved.