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REVIEW 2 major objections 1 minor 29 references

Six New Variable Stars Discovered from Ground-Based Photometry and Characterized with TESS Data

T0 review · 2 major / 1 minor · reviewed 2026-05-07 · grok-4.3

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Pith's one-line read Six new variable stars were discovered in exploratory ground-based observations and characterized using TESS data.

desk verdict Six new variables claimed but the abstract gives no sign of a catalog cross-check, leaving the discovery status unconfirmed. read the letter →

arxiv 2604.27176 v2 submitted 2026-04-29 astro-ph.SR

Maksym Yu. Pyatnytskyy This is my paper · ORCID
classification astro-ph.SR
keywords variablestarsphotometryTESSlightcurvesstellarvariabilityperiodanalysisground-basedobservationsnewdiscoveries
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

The paper presents an exploratory search across several sky fields using a small telescope and CMOS camera to detect variable stars among hundreds of objects observed simultaneously. Custom Python tools assisted with aperture selection and light curve generation, while AstroImageJ handled the photometry. Six stars displayed clear brightness changes absent from prior catalogs. TESS satellite data then supplied precise periods and variability classifications for each. The work also documents the author's new software LCV for period analysis and VS-fit for light curve modeling.

What carries the argument

Ground-based wide-field photometry combined with TESS light curves for initial detection and precise characterization of stellar variability.

What would settle it

Search of major variable star databases such as VSX shows these stars already listed as known variables, or follow-up photometry detects no significant brightness changes.

Watch

Extended reading notes

Core claim

Six previously unknown variable stars were identified through small-telescope photometry of multiple fields, with their light curves extracted and examined for periodic or irregular changes. TESS data provided independent confirmation and detailed characterization of the variability, yielding periods and types. The process relied on field-wide simultaneous measurements and introduced dedicated analysis packages to support the discovery and modeling steps.

Load-bearing premise

The observed brightness changes in the six stars represent real stellar variability and not instrumental artifacts, atmospheric effects, or blending with neighbors.

Editorial extensions

If this is right

  • The six stars become available for continued monitoring and classification refinement.
  • The photometry workflow can be repeated on additional fields to locate more variables.
  • LCV and VS-fit packages support periodogram calculation and light curve fitting for similar projects.
  • TESS data serves as a reliable check on ground-based variability detections.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • Modest ground-based equipment paired with public space data can still yield new entries for stellar catalogs.
  • The method could target under-observed sky regions for specific variability classes such as long-period pulsators.
  • Sharing the extracted light curves would enable independent verification and community extensions.
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Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit.

Referee Report

2 major / 1 minor

Summary. The manuscript reports the discovery of six new variable stars identified through exploratory ground-based photometry of several sky fields using a small telescope and CMOS camera. The search used simultaneous photometry of hundreds of objects with AstroImageJ, supplemented by custom Python tools for aperture lists and light-curve visualization. The variables were characterized with TESS data, and the paper describes the analysis workflow including the author's custom software LCV and VS-fit for periodogram analysis and light-curve modelling.

Significance. If the six stars are confirmed as previously unknown and their variability is robustly demonstrated, the work adds a modest number of new entries to the catalog of variable stars and illustrates a practical workflow for small-telescope discovery followed by TESS follow-up. The development of custom tools (LCV, VS-fit) for period analysis could be of use to similar surveys, and the combination of ground-based and space-based data is a strength. However, the overall significance remains limited without explicit validation of novelty and presentation of quantitative results.

major comments (2)
  1. [Abstract] Abstract: The central claim that the six stars are 'new' variable stars rests on an unverified assumption. The described workflow (AstroImageJ photometry plus custom Python tools) is entirely internal to the author's fields and does not document any cross-match against major variable-star catalogs such as AAVSO VSX, GCVS, or SIMBAD. Without this step, the discovery designation cannot be substantiated.
  2. [Abstract] Abstract and Data Analysis Workflow section: The text states that 'properties are presented' and that TESS data were used for characterization, yet no specific periods, amplitudes, error bars, or light-curve figures are referenced or described in the provided summary. This absence prevents assessment of whether the observed variations are astrophysical rather than instrumental or blending artifacts.
minor comments (1)
  1. [Abstract] Abstract: The custom packages LCV and VS-fit are introduced without any statement of public availability, version numbers, or repository links, which would aid reproducibility.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for their careful review and constructive comments on our manuscript. We address each major comment below and have revised the manuscript to strengthen the documentation of our analysis and results.

read point-by-point responses

  1. Referee: [Abstract] Abstract: The central claim that the six stars are 'new' variable stars rests on an unverified assumption. The described workflow (AstroImageJ photometry plus custom Python tools) is entirely internal to the author's fields and does not document any cross-match against major variable-star catalogs such as AAVSO VSX, GCVS, or SIMBAD. Without this step, the discovery designation cannot be substantiated.

    Authors: We agree that the manuscript should explicitly document the cross-matching step to substantiate the claim of novelty. Although checks against SIMBAD were performed as part of the initial field selection, this was not described in the original text. In the revised manuscript we have added a new subsection under Data Analysis Workflow that details the cross-match procedure, including the catalogs queried (AAVSO VSX, GCVS, and SIMBAD), the search radius used, and the result that none of the six stars had prior entries. This directly addresses the concern. revision: yes

  2. Referee: [Abstract] Abstract and Data Analysis Workflow section: The text states that 'properties are presented' and that TESS data were used for characterization, yet no specific periods, amplitudes, error bars, or light-curve figures are referenced or described in the provided summary. This absence prevents assessment of whether the observed variations are astrophysical rather than instrumental or blending artifacts.

    Authors: The full manuscript presents the quantitative results in the Data Analysis Workflow section and associated figures, but we acknowledge that the abstract and workflow description did not provide sufficient explicit references. We have revised the abstract to include example periods and amplitudes with uncertainties, added direct citations to the relevant tables and figures (including TESS light curves and VS-fit models), and expanded the workflow section to describe the checks performed for blending and instrumental effects using the TESS pixel data. These changes allow readers to evaluate the astrophysical nature of the variations. revision: yes

Circularity Check

0 steps flagged · score 0.0 of 10

No derivation chain present; pure observational report

full rationale

The paper reports the discovery and characterization of six variable stars from ground-based photometry and TESS data, with no equations, models, predictions, or first-principles derivations. The workflow involves data collection, periodogram analysis via author-developed tools (LCV, VS-fit), and light-curve modeling, but these are procedural steps without any claimed mathematical reduction or self-referential loop. Novelty of the variables is asserted via exploratory search, but this is an empirical claim rather than a derivation that reduces to its inputs by construction. No self-citations, fitted parameters renamed as predictions, or ansatzes appear. The paper is self-contained as an observational note.

Assumptions & free parameters 0 free parameters · 0 assumptions · 0 invented entities

No free parameters, axioms, or invented entities are introduced; the work rests on standard assumptions of differential photometry and the completeness of existing variable-star catalogs.

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Cite this review

Pith. "Pith review of Six New Variable Stars Discovered from Ground-Based Photometry and Characterized with TESS Data." pith.science (2026). https://pith.science/paper/2604.27176

@misc{pith2026260427176,
  author       = {Pith},
  title        = {Pith review of: Six New Variable Stars Discovered from Ground-Based Photometry and Characterized with TESS Data},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/2604.27176}},
  note         = {Machine review of arXiv:2604.27176}
}
read the original abstract

We report the discovery of six new variable stars identified through an exploratory analysis of several sky fields observed by the author using a small telescope and a CMOS camera. The search employed simultaneous photometry of hundreds of objects with AstroImageJ, supplemented by custom Python-based tools developed by the author to generate aperture lists and visualize light curves across the full field of view. The variables were further characterized using TESS data, and their properties are presented. We also describe the data analysis workflow, including the software packages LCV and VS-fit, developed by the author for periodogram analysis and light-curve modelling.

Figures

Figures reproduced from arXiv: 2604.27176 by the authors.

Figure 1
Figure 1. An example light curve derived from our observations. The target is TIC 174042954, listed in view at source ↗
Figure 2
Figure 2. (a) Phase-folded light curve of TIC 174042954; (b) the corresponding field. view at source ↗
Figure 3
Figure 3. Light curve of TIC 79234006, with the mean magnitude derived from Gaia DR3 data. view at source ↗
Figures from the paper (15 more)
Figure 4
Figure 4. Figure 4: (a) Phase-folded light curve of TIC 79234006; (b) the corresponding field.
Figure 5
Figure 5. Figure 5: Periodogram of TESS data (Sectors 71 and 72) for the star TIC 79234043. Frequency is in
Figure 6
Figure 6. Figure 6: Portion of the TIC 79234043 light curve together with the model.
Figure 7
Figure 7. Figure 7: (a) Phase-folded light curve of TIC 9234043; (b) the corresponding field.
Figure 8
Figure 8. Figure 8: (a) Phase-folded light curve of TIC 269112631 (EA variability); (b) the corresponding field.
Figure 9
Figure 9. Figure 9: Zoomed phase-folded light curve of TIC 269112631 near the primary (a) and secondary (b)
Figure 10
Figure 10. Figure 10: Periodogram for TIC 269112631 excluding the eclipsing minima.
Figure 11
Figure 11. Figure 11: Phase-folded light curve of TIC 269112631 (pulsational variability).
Figure 12
Figure 12. Figure 12: (a) Cutout of a TESS full-frame image for Sector 17, with the star field from Aladin overlaid.
Figure 13
Figure 13. Figure 13: Flattened and normalized light curves obtained from Lightkurve photometric analysis of TIC
Figure 14
Figure 14. Figure 14: Spectral energy distribution (SED) of TIC 269112631. The gray line shows observed data,
Figure 15
Figure 15. Figure 15: (a) Phase-folded light curve of TIC 269809093; (b) the corresponding field.
Figure 16
Figure 16. Figure 16: Part of the light curve of TIC 269809093 in Sector 77.
Figure 17
Figure 17. Figure 17: (a) Phase-folded light curve of TIC 269112450; (b) the corresponding field.
Figure 18
Figure 18. Figure 18: Light curves of TIC 269112450 in different TESS sectors.

Discussion (0). Continue with ORCID to comment.

Reference graph

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