Geology (from the Ancient Greek γῆ, gē, i.e. "earth" and -λoγία, -logia, i.e. "study of, discourse") is an earth science concerned with the solid Earth, the rocks of which it is composed, and the processes by which they change over time. Geology can also refer to the study of the solid features of any terrestrial planet or natural satellite, (such as Mars or the Moon).
Andrew Herbert Knoll. Gaidos E, Knoll AH. Frontiers of Astrobiology. Cambridge: Cambridge University Press; 2012. Our evolving planet: From dark ages to evolutionary renaissance. pp. 132–153.
Josiah Gilbert Holland, in Rev. S. Pollock Linn Golden Gleams of Thought from the Words of Leading Orators, Divines, Philosophers, Statesmen and Poets, A.C. McClurg & Company, 1881, p. 280.
Using light to produce either electricity or hydrogen, dye-sensitised solar cells (DSSCs) are currently the most efficient third-generation solar technology. Increases in their conversion efficiency through better understanding of how light-absorption materials function will make them attractive for large-scale deployment.