In this work we will create the Secular Light Curve (SLC) of exocomet 3I/ATLAS, using the SLC-Methodology (Ferrin 2010-2023). The SLCs give a throve of new information and allow the comparison of exo-comets with comets of our own solar system. We arrive at the following conclusions: The colors of 3I are consistent and lie inside the area of colors of other comets in our solar system. The SLC of this comet exhibits a photometric anomaly, a region from -120 to -45 days before perihelion that we interpreted as an eclipse, suggesting that 3I might also be a binary. At -45 days, the SLC changes abruptly its slope, reaching a maximum absolute magnitude of mV(1,1,{\alpha}) = 6.8+-0.1. Using reported estimates derived from 97 papers in the arXiv.org depository for the size, dust, H2O, CO2, and CO production rates, we calculate the total mass loss. We use the inverse total mass loss, as a proxy for age. The Mass-Loss Age = 0.16 comet years will be plotted in the horizontal axis of a Comet Evolutionary Diagram (CED) while the number of Remaining Returns defined as RR = r/{\Delta}r = 24, will be plotted in the vertical axis of the CED. 3I/ATLAS exocomet lies among the comets of our Oort comet family. We conclude that 3I is a comet of the Oort Cloud, but from a different stellar system. The Evolutionary Diagram presented in this work shows complexity beyond current understanding
@article{arxiv.2604.09941,
title = {Secular Light Curve of Exocomet 3I/ATLAS, and its Location on a Comet Evolutionary Diagram},
author = {Ignacio Ferrin and Jose Garrido and Charles Triana and Giuliat Navas and Raul Melia and Santiago Perez and Emiliano Gomez and Jorge Andrey Vargas and Juan Hincapie and Brayan Quintero},
journal= {arXiv preprint arXiv:2604.09941},
year = {2026}
}