VERDICT: TRUE The viral claim about Taam Ja' is substantively accurate. Every material assertion — the Mayan name meaning, the >420 m depth with no bottom reached, the instrument/cable limit reached before hitting bottom, the deepest-blue-hole status, and the deep-water temperature/salinity matching Caribbean rather than bay water — is confirmed by the primary scientific literature and the institution that made the discovery. Two caveats (timing of the probe drop and the "ran out of cable" phrasing) are noted below, but they don't change the verdict. **Primary sources used (both opened and read):** 1. Alcérreca-Huerta et al., "Recent records of thermohaline profiles and water depth in the Taam ja' Blue Hole (Chetumal Bay, Mexico)," *Frontiers in Marine Science* (peer-reviewed), 29 April 2024 — https://www.frontiersin.org/journals/marine-science/articles/10.3389/fmars.2024.1387235/full 2. El Colegio de la Frontera Sur (ECOSUR)–CONAHCYT official release (the discoverers' own institution, a public Mexican research center): "Agujero azul de Taam ja' en la bahía de Chetumal, México, es el más profundo del mundo" — https://www.ecosur.mx/agujero-azul-de-taam-ja-en-la-bahia-de-chetumal-mexico-es-el-mas-profundo-del-mundo-ecosur-conahcyt/ 3. Supporting (original discovery paper): Alcérreca-Huerta et al., *Frontiers in Marine Science*, 23 Feb 2023 — https://www.frontiersin.org/journals/marine-science/articles/10.3389/fmars.2023.1141160/full **Claim-linked findings:** - **Depth >420 m, no bottom, deepest known blue hole:** The 2024 peer-reviewed paper reports CTD casts on 6 and 13 December 2023 that "recorded 416.0 and 423.6 mbsl," stating: "these new findings unequivocally establish the Taam Ja' Blue Hole (TJBH) as the world's deepest known blue hole, with its bottom still not reached." The ECOSUR–CONAHCYT release independently states measurements "superan los 420 metros por debajo del nivel del mar, sin que se haya determinado la profundidad exacta del fondo" (>420 m below sea level, exact bottom depth undetermined), making it "el más profundo en el mundo hasta ahora conocido." - **Probe on a cable that ran out before the bottom (with caveats):** The paper says the team lowered a Valeport SWiFT CTD profiler "utilizing ~500 m of cable down to the bottom, adhering to the maximum depth supported by the instrument," and no bottom was reached. Caveats: (1) the fieldwork was done on Dec 6 & 13, **2023**, and reported/published in **April 2024** — so "in 2024, scientists lowered a probe" reflects the announcement year, not the deployment; (2) the paper technically notes the CTD's 423.6 m reading was less than the full ~500 m of cable because the instrument descended obliquely (~32–34° from vertical), so "ran out of cable" is a loose paraphrase of "the instrument/cable reached its deployment limit without finding the bottom." - **Deep water matches Caribbean, not the shallow bay above:** The paper shows that below ~400 mbsl, temperature rises sharply (≈19.8 → 23.9 °C) and salinity climbs to 37.5 PSU (avg. 36.0 ± 0.74 PSU), values that "gradually converge with those of the Caribbean Sea" (Caribbean surface water reaches up to 36.9 PSU at 115–150 m) — in contrast to the estuarine Chetumal Bay surface water above the hole (salinity <17 PSU, temp >25 °C). The authors conclude "this data alignment suggests a potential subterranean connection between these water bodies and the TJBH." The ECOSUR release says the same: deep water properties resembled the Caribbean Sea at 0–150 m, "lo que sugiere la probable existencia de conexiones subterráneas entre la bahía de Chetumal y el mar Caribe." - **Name = "deep water" in Mayan; location:** The 2023 discovery paper states the feature "is the now named Taam ja' Blue Hole (i.e., deep water in Mayan)," located in Chetumal Bay on the southeastern coast of the Yucatán Peninsula, Mexico. ECOSUR likewise translates it as "agua profunda" in reference to Mayan culture. **Minor framing notes (don't change the verdict):** The hole sits inside Chetumal Bay — a coastal estuary, not the open ocean — rather than literally "off the coast"; "no known bottom" is accurate in that no expedition has reached or confirmed it; and the Caribbean link is presented in the paper as a strong hypothesis ("hints"), exactly as the TikTok describes it, not as proven fact.