{"about":{"site":"https://codewithpapers.app","non_affiliation":"Code with Papers and Syntology are not affiliated with, endorsed by, or sponsored by Papers with Code, Meta, or the pwc-archive mirror.","licence":"CC BY-SA 4.0","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","attribution":"https://codewithpapers.app/attribution","modified":"archive material modified by Syntology; see the attribution page"},"url":"/paper/transit-origami-a-method-to-coherently-fold","title":"Transit Origami: A Method to Coherently Fold Exomoon Transits in Time Series Photometry","arxiv_id":"2108.02903","date":"2021-08-06","proceeding":null,"authors":["David Kipping"],"abstract":"One of the simplest ways to identify an exoplanetary transit is to phase fold a photometric time series upon a trial period - leading to a coherent stack when using the correct value. Such phase-folded transits have become a standard data visualisation in modern transit discovery papers. There is no analogous folding mechanism for exomoons, which would have to represent some kind of double-fold; once for the planet and then another for the moon. Folding with the planet term only, a moon imparts a small decrease in the surrounding out-of-transit averaged intensity, but its incoherent nature makes it far less convincing than the crisp stacks familiar to exoplanet hunters. Here, a new approach is introduced that can be used to achieve the transit origami needed to double fold an exomoon, in the case where a planet exhibits TTVs. This double fold has just one unknown parameter, the satellite-to-planet mass ratio, and thus a simple one-dimensional grid search can be used to rapidly identify power associated with candidate exomoons. The technique is demonstrated on simulated light curves, exploring the breakdown limits of close-in and/or inclined satellites. As an example, the method is deployed on Kepler-973b, a warm mini-Neptune exhibiting an 8 minute TTV, where the possibility that the TTVs are caused by a single exomoon is broadly excluded, with upper limits probing down to a Ganymede-sized moon.","url_abs":"https://arxiv.org/abs/2108.02903v1","url_pdf":"https://arxiv.org/pdf/2108.02903v1.pdf","source":{"archive":"pwc-archive (Hugging Face), CC BY-SA 4.0","snapshot":"2025-07-28","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","row_kind":"links_only","authors_date_abstract":"arXiv metadata, CC0 1.0 (https://info.arxiv.org/help/license), from the Kaggle arXiv metadata snapshot of 2026-09-12"},"code_links":[{"paper_slug":"transit-origami-a-method-to-coherently-fold","repo_url":"https://github.com/CoolWorlds/TransitOrigamiBits","is_official":1,"mentioned_in_paper":1,"mentioned_in_github":0,"framework":"none","reach":null}],"tasks":[],"methods":[],"datasets_introduced":[],"methods_introduced":[],"results":[],"syntology":{"atlas_url":null,"mcp":null,"developers":"https://syntology.ai/developers"},"arxiv_metadata":null,"syntology_extracted_results":null}