Exoplanets, -moons, -comets

Visual Inspection Of Potential Exocomet Transits Identified Through Machine Learning And Statistical Methods

By Keith Cowing
Status Report
astro-ph.EP
February 7, 2026
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Visual Inspection Of Potential Exocomet Transits Identified Through Machine Learning And Statistical Methods
Step-by-step procedure of the transit encapsulation in the TIC 020209388 light curve. The X-axis and Y-axis specify time in days and normalized flux, respectively. Top panel: 1 — simulated transit profile, 2 — PDC_SAP normalized flux of the star from sector 1 TESS dataset, both selected randomly; bottom panel, 3 — the light curve of the star with the encapsulated transit, 4 — zoomed span of the light curve in the vicinity of the encapsulated transit. — astro-ph.EP

In this work, we explore several ways to detect possible exocomet transits in the TESS (The Transiting Exoplanet Survey Satellite) light curves. The first one has been presented in our previous work, a machine learning approach based on the Random Forest algorithm.

It was trained on asymmetric transit profiles calculated as a result of the modelling of a comet transit, and then applied to real star light curves from Sector 1 of TESS. This allowed us to detect 32 candidates with weak and non-periodic brightness dips that may correspond to comet-like events.

The aim of this work is to analyse the events identified by the visual inspection to make sure that the features detected were not caused by instrumental effects. The second approach to detect possible exocomet transits, which is proposed, is an independent statistical method to test the results of the machine learning algorithm and to look for asymmetric minima directly in the light curves.

This approach was applied to beta Pictoris light curves using TESS data from Sectors 5, 6, 32, and 33. The algorithm reproduced nearly all previously known events deeper than 0.03 % of the star flux, showing that it is efficient to detect shallow and irregular flux changes in the different sectors of the TESS data and at the different levels of noise.

The combination of machine learning, visual inspection, and statistical analysis facilitates the identification of faint and short-lived asymmetric transits in photometric data. Although the number of confirmed exocomet transits is still small, the growing amount of observations points to their likely presence in many young planetary systems.

D.V. Dobrycheva, I.V. Kulyk, D.R. Karakuts, M.Yu. Vasylenko, Ya.V. Pavlenko, O.S. Shubina, I.V. Luk’yanyk

Comments: 14 pages, 14 figures, 30 references
Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Instrumentation and Methods for Astrophysics (astro-ph.IM)
MSC classes: 85A35, 85-08
ACM classes: I.2.6; J.2
Cite as: arXiv:2602.02701 [astro-ph.EP](or arXiv:2602.02701v1 [astro-ph.EP] for this version)
https://doi.org/10.48550/arXiv.2602.02701
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Related DOI:
https://doi.org/10.15407/knit2025.06.080
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Submission history
From: Daria Dobrycheva
[v1] Mon, 2 Feb 2026 19:12:44 UTC (1,167 KB)
https://arxiv.org/abs/2602.02701

Astrobiology, Interstellar,

Explorers Club Fellow, ex-NASA Space Station Payload manager/space biologist, Away Teams, Journalist, Lapsed climber, Synaesthete, Na’Vi-Jedi-Freman-Buddhist-mix, ASL, Devon Island and Everest Base Camp veteran, (he/him) 🖖🏻