{ "id": "epgv5vc74y", "slug": "145452-ritona", "title": "145452 Ritona", "updated": "2026-10-25", "topic_path": [ { "id": "places", "label": "Places and geography", "api_url": "https://www.edgepedia.org/api/v1/topics/places" }, { "id": "places.extraterrestrial", "label": "Extraterrestrial places", "api_url": "https://www.edgepedia.org/api/v1/topics/places.extraterrestrial" }, { "id": "places.extraterrestrial.small-bodies", "label": "Small bodies of the Solar System", "api_url": "https://www.edgepedia.org/api/v1/topics/places.extraterrestrial.small-bodies" }, { "id": "places.extraterrestrial.small-bodies.kuiper-belt-and-tnos", "label": "Kuiper belt and trans-Neptunian objects", "api_url": "https://www.edgepedia.org/api/v1/topics/places.extraterrestrial.small-bodies.kuiper-belt-and-tnos" } ], "geo": [ { "id": "geo.nongeo.nodate.places.extraterrestrial.small-bodies", "label": "Non-geographic · Not dated: Small bodies of the Solar System", "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.nodate.places.extraterrestrial.small-bodies", "path": [ { "id": "geo.nongeo", "label": "Non-geographic", "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo" }, { "id": "geo.nongeo.nodate", "label": "Non-geographic · Not dated", "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.nodate" }, { "id": "geo.nongeo.nodate.places", "label": "Places and geography", "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.nodate.places" }, { "id": "geo.nongeo.nodate.places.extraterrestrial", "label": "Extraterrestrial places", "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.nodate.places.extraterrestrial" }, { "id": "geo.nongeo.nodate.places.extraterrestrial.small-bodies", "label": "Small bodies of the Solar System", "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.nodate.places.extraterrestrial.small-bodies" } ] } ], "excerpt": "145452 Ritona is a large classical Kuiper belt object roughly 679 km across, discovered in September 2005 at Apache Point Observatory and described as a possible dwarf planet.", "snippet": "145452 Ritona is a large classical Kuiper belt object roughly 679 km across, discovered in September 2005 at Apache Point Observatory and described as a possible dwarf planet.", "node": "places.extraterrestrial.small-bodies.kuiper-belt-and-tnos", "markdown": "# 145452 Ritona\n\nWith a diameter of roughly 679 km it is large enough that it has been described as a possible dwarf planet[1](https://www.spacereference.org/asteroid/145452-2005-rn43).\n\n| Key fact | Detail |\n|---|---|\n| Discovery | 10 September 2005, Apache Point Observatory, by Andrew C. Becker, Andrew W. Puckett, and Jeremy M. Kubica[2](https://markandrewholmes.com/ritona.html) |\n| Brightness | Absolute magnitude H = 3.70 mag[3](https://planety.astro.cz/planetka-145452) |\n\n## Discovery and naming\n\nRitona was discovered on 10 September 2005 by Andrew C. Becker, Andrew W. Puckett, and Jeremy M. Kubica at [Apache Point Observatory](https://www.edgepedia.org/apache-point-observatory) near Sunspot, New Mexico[2](https://markandrewholmes.com/ritona.html) • [3](https://planety.astro.cz/planetka-145452). The [Minor Planet Center](https://www.edgepedia.org/minor-planet-center) published the discovery in MPEC 2006-O25 on 23 July 2006, together with the neighboring object [145451 Rumina](https://www.edgepedia.org/145451-rumina), found by the same team[4](https://solar-system-and-the-universe.fandom.com/wiki/Solar_System_Discovery_Timeline).\n\nThe name honors a Celtic water goddess. Ritona was a goddess of river fords among the Treveri, a Celtic tribe of the Moselle river valley in France; ancient inscriptions describe her as a protective deity of watercourses and of the ford across the Saar, and she has also been interpreted as a goddess of trade[2](https://markandrewholmes.com/ritona.html). The naming of the asteroid was announced by the International Astronomical Union's Working Group for Small Body Nomenclature on 21 July 2025, and the name appears in WGSBN Bulletin 5, #17[5](https://www.wgsbn-iau.org/files/Bulletins/V005/WGSBNBull_V005_017.pdf).\n\n## Orbit and classification\n\nBecause it lies in the classical [Kuiper belt](https://www.edgepedia.org/kuiper-belt) at 39 to 48 AU, Ritona is classified as a classical Kuiper belt object, sometimes called a cubewano.\n\nPublished orbit solutions disagree on the timing of the perihelion passages. One account states that Ritona last passed perihelion in November 1760 and will next pass it on 15 April 2029, while a computation from Minor Planet Center elements places the passages at 28 December 1766 and 12 November 2034[3](https://planety.astro.cz/planetka-145452). The same Czech computation finds the object's closest approach to Earth in the coming decades at 39.56 AU on 28 September 2034, when it should also be near its brightest from Earth at magnitude 19.7[3](https://planety.astro.cz/planetka-145452). Orbital simulations by NASA JPL's CNEOS show no close approaches to Earth[1](https://www.spacereference.org/asteroid/145452-2005-rn43).\n\n## Physical properties\n\nThe surface is red.\n\nA 2017 photometric study of nine trans-Neptunian objects and centaurs improved the precision of the previously reported rotation period for 2005 RN43 using both new and literature data[6](https://arxiv.org/abs/1712.04284).\n\n## Observation record\n\nRitona is unusually well observed for a distant object. As of a May 2026 reference date, 1,250 observations across 31 oppositions spanning 1954 to 2025 had been used in the orbit solution, with the most recent observation on 6 December 2025[3](https://planety.astro.cz/planetka-145452). This long observational arc is what allows a secure orbit for an object whose revolution period exceeds two and a half centuries.\n\n## References\n\n1. [Asteroid 145452 (2005 RN43), Space Reference](https://www.spacereference.org/asteroid/145452-2005-rn43)\n2. [Ritona, Mark Andrew Holmes](https://markandrewholmes.com/ritona.html)\n3. [Planetka Ritona (145452), Planety sluneční soustavy](https://planety.astro.cz/planetka-145452)\n4. [Solar System Discovery Timeline, Solar System and the Universe Wiki](https://solar-system-and-the-universe.fandom.com/wiki/Solar_System_Discovery_Timeline)\n5. [WGSBN Bulletin 5, #17, IAU Working Group for Small Body Nomenclature](https://www.wgsbn-iau.org/files/Bulletins/V005/WGSBNBull_V005_017.pdf)\n6. [Photometric observations of nine Transneptunian objects and Centaurs, arXiv:1712.04284](https://arxiv.org/abs/1712.04284)\n\n---\n*Topic: Encyclopedia › Places and geography › Extraterrestrial places › Small bodies of the Solar System › Kuiper belt and trans-Neptunian objects*\n\n*Initially written Oct 21, 2026 · Edited: Oct 25, 2026*\n\n*Copyright 2026 EdgeChat AI, a subsidiary of Biostate AI.*\n\nLicense: Edgepedia Community License 1.0, https://www.edgepedia.org/edgepedia/license\n", "same_as": [], "url": "https://www.edgepedia.org/145452-ritona", "markdown_url": "https://www.edgepedia.org/145452-ritona.md", "license": { "name": "Edgepedia Community License 1.0", "url": "https://www.edgepedia.org/edgepedia/license", "summary": "Free with credit, commercial use included. AI training is open to everyone. For other uses, organizations over USD 100M in revenue or 100M monthly users license separately.", "spdx": "LicenseRef-Edgepedia-Community-1.0" }, "credit": "\"145452 Ritona\", Edgepedia (EdgeChat), https://www.edgepedia.org/145452-ritona. Edgepedia Community License 1.0.", "credit_md": "\"[145452 Ritona](https://www.edgepedia.org/145452-ritona)\", Edgepedia (EdgeChat), [https://www.edgepedia.org/145452-ritona](https://www.edgepedia.org/145452-ritona). [Edgepedia Community License 1.0](https://www.edgepedia.org/edgepedia/license).", "credit_html": "\"145452 Ritona\", Edgepedia (EdgeChat), https://www.edgepedia.org/145452-ritona. Edgepedia Community License 1.0.", "speakable": "145452 Ritona is a large classical Kuiper belt object roughly 679 km across, discovered in September 2005 at Apache Point Observatory and described as a possible dwarf planet." }