Gaia-GIC-1: An Evolving Catastrophic Planetesimal Collision Candidate

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Tzanidakis, Anastasios, Davenport, James R. A.
Formato: Preprint
Publicado: 2026
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866915854477688832
author Tzanidakis, Anastasios
Davenport, James R. A.
author_facet Tzanidakis, Anastasios
Davenport, James R. A.
contents We report the discovery of the optical dipper and low-luminosity infrared stellar transient Gaia20ehk (hereafter, Gaia-GIC-1), which is currently undergoing high-amplitude variability due to transiting dusty material. In this work, we identify Gaia-GIC-1 as a likely young F-type star based on the spectral energy distribution before the onset of the high-amplitude optical variability. We detect a significant periodic modulation of 380.5 days in Gaia-G band before the onset of the infrared brightening, consistent with a $\sim$1.1 AU orbit assuming circular orbits and a 1.3 M$_{\odot}$ star. The system has remained in an infrared bright state for $>$4 years since the last near-infrared detection, confirmed by recent SPHEREx observations, while continuing to undergo large amplitude irregular optical dimming. We measure the dust temperature from the freshly generated debris to be $\sim$900 Kelvin based on available WISE photometry, and the dust clump size to have a minimum cross-sectional area of 0.13 AU$^{2}$, and the dust mass $4\times 10^{20}$ kg. Currently, optical follow-up spectroscopy has not revealed any prominent features in the system, likely due to its highly variable nature. We hypothesize that Gaia-GIC-1 represents debris recently formed in a planetary collision, which produced a clumpy dust cloud on a bound orbit, producing the observed dimming events. The ongoing collisional activity in this system presents a unique opportunity for understanding terrestrial planet formation.
format Preprint
id arxiv_https___arxiv_org_abs_2603_10952
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Gaia-GIC-1: An Evolving Catastrophic Planetesimal Collision Candidate
Tzanidakis, Anastasios
Davenport, James R. A.
Earth and Planetary Astrophysics
Solar and Stellar Astrophysics
We report the discovery of the optical dipper and low-luminosity infrared stellar transient Gaia20ehk (hereafter, Gaia-GIC-1), which is currently undergoing high-amplitude variability due to transiting dusty material. In this work, we identify Gaia-GIC-1 as a likely young F-type star based on the spectral energy distribution before the onset of the high-amplitude optical variability. We detect a significant periodic modulation of 380.5 days in Gaia-G band before the onset of the infrared brightening, consistent with a $\sim$1.1 AU orbit assuming circular orbits and a 1.3 M$_{\odot}$ star. The system has remained in an infrared bright state for $>$4 years since the last near-infrared detection, confirmed by recent SPHEREx observations, while continuing to undergo large amplitude irregular optical dimming. We measure the dust temperature from the freshly generated debris to be $\sim$900 Kelvin based on available WISE photometry, and the dust clump size to have a minimum cross-sectional area of 0.13 AU$^{2}$, and the dust mass $4\times 10^{20}$ kg. Currently, optical follow-up spectroscopy has not revealed any prominent features in the system, likely due to its highly variable nature. We hypothesize that Gaia-GIC-1 represents debris recently formed in a planetary collision, which produced a clumpy dust cloud on a bound orbit, producing the observed dimming events. The ongoing collisional activity in this system presents a unique opportunity for understanding terrestrial planet formation.
title Gaia-GIC-1: An Evolving Catastrophic Planetesimal Collision Candidate
topic Earth and Planetary Astrophysics
Solar and Stellar Astrophysics
url https://arxiv.org/abs/2603.10952