Exploring the Two Overlapping Galaxies LEDA 2073461 and SDSS J115331.86

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Authors: Hongjun Pan
Cited by: 0

Abstract

The overlapping spiral galaxies LEDA 2073461 and SDSS J115331.86 form an exceptional system that enables direct examination of spiral‑arm morphology and formation mechanisms. The foreground galaxy, LEDA 2073461, is a well‑defined grand‑design spiral galaxy whose inter‑arm regions contain extremely low‑density interstellar material, producing only minimal obscuration of the background galaxy. This “low‑density” characterization is supported by comparison with the overlapping system NGC 3314, in which the background galaxy NGC 3314b is heavily obscured by the foreground galaxy NGC 3314a due to its higher inter‑arm material density. Such transparency in LEDA 2073461 is difficult to reconcile with the expectations of classical Density Wave Theory, which requires substantial interstellar mass to sustain long‑lived density enhancements. Instead, the observations favor a central‑driven emission mechanism for the formation and maintenance of its spiral structure.The background galaxy SDSS J115331.86 exhibits a distinctive morphology defined by an 8‑shaped double‑ring configuration and a chain‑link spiral‑arm crossing pattern, consistent with the crossing behavior previously described by the author. The visibility of multiple arm segments—together with their luminosity gradients, curvature‑extension trends, and geometric relationships—combined with the assumption of central symmetry, enables a robust reconstruction of the galaxy’s intrinsic structure despite partial obscuration by the foreground system.Together, this overlapping pair provides a rare natural laboratory for testing competing models of spiral‑arm formation and for identifying non‑classical spiral morphologies that challenge traditional theoretical frameworks.

Fields of Study & Subjects

Galaxies: Formation Evolution Phenomena Stellar planetary and galactic studies Astrophysical Phenomena and Observations

Publication details

Journal / source
Preprints.org
Publication date
27 January 2026
Document type
Preprint