Preliminary Photometric and Morphological Results of the Interstellar Comet 3I/ATLAS Vega del Thader Astronomical Observatory (MCP J70 IAU) José Pablo Navarro Pina

Abstract

This report presents a preliminary analysis of the photometric and morphological properties of the interstellar comet 3I/ATLAS, based on early imaging data obtained by the Vega del Thader Astronomical Observatory. The observations reveal complex coma structures, evidence of multi-volatile activity, and brightness asymmetries that suggest a heterogeneous nucleus. These initial findings contribute to the ongoing effort to characterize interstellar objects passing through the Solar System.

1. Introduction

Comet 3I/ATLAS represents one of the few known interstellar visitors detected within our Solar System. Its photometric behavior, morphology, and apparent asymmetries offer valuable insights into the composition and activity of small bodies formed beyond our stellar environment. The following sections summarize the visual analysis and first-order interpretations derived from the observational dataset.

2. Visual and Morphological Analysis

The image analysis (Figure 1) shows a dense central condensation surrounded by an extended coma. Brightness gradients indicate a directional asymmetry consistent with anisotropic dust emission. The apparent tail extends in the anti-solar direction, with secondary faint structures diverging at small angles, possibly indicating jet-like outflows or dust filaments generated by rotational modulation. No clear stellar contamination was observed near the central condensation, ensuring a reliable photometric profile.

3. Preliminary Results

Photometric extraction suggests that the comet exhibits a sustained level of activity even at large heliocentric distances, likely driven by supervolatile species such as CO or CO₂. The coma shows a gradual radial fading, consistent with dust-dominated scattering rather than gas-dominated fluorescence. The inner region appears optically thick, while the outer coma transitions into a diffuse, isotropic envelope. The observed morphology supports the hypothesis of heterogeneous surface activity, with localized jets contributing to the asymmetric brightness distribution.

4. Conclusions and Future Work

The preliminary analysis of 3I/ATLAS highlights the dynamic nature of interstellar cometary nuclei. The asymmetric coma, sustained brightness, and possible multi-volatile activity suggest a nucleus with complex composition and surface variability. Continued monitoring, polarimetric imaging, and spectroscopic data will be essential to quantify the dust-to-gas ratio and constrain the origin and physical properties of this object. These findings contribute to the growing body of evidence that interstellar comets may preserve pristine materials from their natal molecular clouds, providing unique insight into the diversity of planetary system formation across the galaxy.