Swimming Beneath
the Eclipse

This document constitutes the formal project submitted by the Asociación Civil Open Water Río Negro in support of its application for the creation and international recognition of a new Guinness World Records title: Most people to complete an open water swim during a solar eclipse.

The proposal is not speculative. It is anchored to a fully planned, funded and institutionally supported sporting event — OWeclipse 2027 — to be staged on Saturday 6 February 2027 at Las Grutas, on the shore of the Gulf of San Matías, in the Argentine province of Río Negro. On that morning, an annular solar eclipse will sweep across the southern cone of South America, and its path will pass directly over the venue. At 10:31:40 local time, at the precise instant the Moon makes first contact with the solar disc as observed from Las Grutas, several hundred swimmers will enter the Atlantic to complete a 2,500-metre marked sea course. They will leave the water before the eclipse reaches its annular phase, and will then witness the "ring of fire" from the shore through certified viewing glasses.

The record sought is a people-based, mass-participation record. It measures neither speed nor distance, but the number of individuals who successfully complete an open water crossing inside a temporal window whose boundaries are fixed not by an organiser, a rulebook or a stopwatch, but by celestial mechanics. It is, in this precise sense, unlike any record currently held in the Guinness World Records archive.

The remainder of this document sets out the case for recognition in full: the criteria the proposed title satisfies (Section 3), the demonstrable absence of any precedent (Section 4), the astronomical basis of the challenge (Section 5), the operational and safety architecture of the event (Sections 6–8), the verification and evidentiary system (Section 9), and — critically — the long-term global framework that makes the title a durable and contestable one rather than a one-off curiosity (Section 10).

2.1 The Organising Body

The Asociación Civil Open Water Río Negro is a civil association constituted under Argentine law for the promotion of open water swimming in the province of Río Negro. It is the organising authority for OWeclipse 2027 and the party that will assume full responsibility before Guinness World Records for compliance with all guidelines, measurement criteria and evidentiary requirements attaching to the proposed title.

• Lucas Nogues
• Juan Facundo Albacete Colombo
• Bruno Grun
• Lucas Puyen Lema

2.2 The Event: OWeclipse 2027

OWeclipse 2027 — Open Water Special Edition — is an open water swimming crossing conceived as a single, indivisible convergence of sport, sea and sky. Its identity, its start time, its course and its safety plan all derive from one immovable fact: the annular solar eclipse of 6 February 2027, which will reach 85.97% obscuration directly above Las Grutas.

The event is designed so that sport and astronomical spectacle complement one another without risk. The swimmers set off exactly as the Moon begins to bite into the Sun, and they are out of the water before the sky reaches its deepest darkening — free, then, to watch the maximum of the eclipse from the beach with their certified glasses. It is, quite literally, swimming beneath the eclipse.

Guinness World Records requires that any new title be clearly defined, objectively measurable, verifiable by independent evidence, standardisable for future attempts, and capable of being broken. The proposed title satisfies each of these criteria without qualification. Each is addressed in turn below.

This section addresses the point on which the applicants place the greatest emphasis, and which they submit is decisive: a competition of these characteristics, under these particular conditions, has never taken place.

4.1 What has existed before

Mass-participation open water swims are common and well established. Solar eclipses are observed, filmed, studied and celebrated by millions. Eclipse-adjacent events — festivals, gatherings, viewing parties, running races timed loosely to eclipse day, marathons and cycling events staged in the general vicinity of an eclipse path — have been held. But in every such case, the astronomical event is a backdrop, a marketing frame, or a coincidence of date. It does not govern the competition.

4.2 What has never existed

What has never existed is a sporting competition whose governing clock is the eclipse itself: whose start gun is fired not at a time chosen by a race director, but at the instant an independent astronomer certifies first contact; whose cut-off is not a duration set by regulation, but the arrival of the eclipse's maximum phase; and whose entire validity therefore rests on a temporal window drawn by orbital mechanics.

Any one of these conditions, taken alone, is unremarkable. Their combination has, to the applicants' knowledge and after due search, never been assembled. OWeclipse 2027 will be the first occasion in recorded history on which a mass open water swimming competition is contested inside the temporal window of a solar eclipse under independent international verification.

4.3 Why it has not been done before

The reason is structural rather than accidental. To stage such an event, four independently improbable conditions must coincide: an eclipse of sufficient magnitude; a path of annularity or totality that crosses navigable, swimmable coastal water; a coastline with the tidal, thermal and logistical conditions permitting mass open water participation on that specific morning; and an organising body with the technical, institutional and safety capacity to deliver it. At Las Grutas on 6 February 2027, all four conditions coincide.

On 6 February 2027 the band of annularity of the eclipse crosses the south of South America and traverses Argentine Patagonia, passing directly over the region of Las Grutas. There the Moon will cover 85.97% of the solar disc, leaving a brilliant "ring of fire" visible in the sky. It is an event that will not recur in the region for decades.

5.1 Eclipse data at Las Grutas (40°45′S, 64°59′W)

5.2 The precision of the trigger

First contact at Las Grutas occurs at 10:31:39. The competition starts at 10:31:40 — one second later, the first full second of the eclipse. This is not an approximation and not a symbolic gesture. The start time is derived from official data published by international astronomical bodies and will be confirmed, on the morning itself, by direct instrumental observation.

The distinction matters for the integrity of the record. A predicted time is a computation; a certified time is an observation. The record requires the second. The CONICET astronomer acting as independent technical authority will verify the exact instant at which the partial eclipse becomes visible from the site, will officially certify that moment, and only then will authorise the start of the crossing.

6.1 The crossing

The crossing takes place entirely at sea, over a buoyed circuit of 2,500 metres in front of the beach at Las Grutas. The route takes advantage of the morning's rising tide, which assists the swimmers' progress and improves safety conditions. The event is designed to be completed in approximately one hour, with the start at 10:31:40 — at the very onset of the eclipse — and all swimmers out of the water before 11:30.

6.2 Course profile

• Distance: 2,500 metres (circuit measured at 2,508 m).
• Setting: the Argentine Sea — Gulf of San Matías, waters of great clarity and wide tidal range.
• Tidal condition: start on a rising tide; high water occurs at 12:10, coinciding with the maximum of the eclipse.
• Swimmer profile: open water swimmers, triathletes and experienced amateurs accustomed to swell and current.

6.3 Conditions of validity for the record

For a participant to be counted towards the record, all of the following must hold:

The official result of the record will be determined solely by the number of participants who satisfy all four conditions. No other factor — position, time, category or age — bears upon the count.

The schedule below is the operational heart of the project. Every element of the event is subordinated to it, and it is this schedule that makes the record both possible and safe. The swimmers set off exactly as the eclipse begins; they are out of the water before the sky reaches its greatest darkening; they then watch the maximum from the shore.

7.1 Accreditation

Accreditation of participants takes place on Friday 5 February, from 14:00 to 19:00. Individual registration, unique identification and the issue of timing devices are completed at this stage, so that the count of eligible starters is fixed and documented before the morning of the attempt.

Safety in maritime waters is the absolute priority of OWeclipse. The event operates under a specific Operational Safety Plan (Plan de Seguridad Operacional) for sea swimming, with particular attention to tides, swell and visibility conditions during the development of the eclipse.

The applicants draw the attention of Guinness World Records to a point of substance: the safety architecture is not an adjunct to the record attempt but a constitutive part of it. The record measures how many people can be brought safely across open sea inside a fixed astronomical window. A safety failure is therefore not merely an operational failure — it is a failure of the achievement itself.

8.1 Measures in force

• Official lifeguards: the lifeguard corps of the Las Grutas beach, together with personnel of the Argentine Naval Prefecture (Prefectura Naval Argentina).
• Assistance flotilla: fast rescue craft, jet skis and support kayakers deployed along the length of the buoyed circuit.
• Signage and marking: the route marked with high-visibility buoys and reference vessels.
• Medical assistance: ambulance and medical team stationed on the beach, at both start and finish.
• Tidal control: permanent monitoring of the rising tide; exit from the water scheduled before the maximum of the eclipse.
• Post-race services: hydration, healthy lunch, and distribution of certified glasses for safe observation of the eclipse.

8.2 The eclipse and in-water visibility

A specific and, so far as the applicants are aware, entirely novel operational question arises in this event: the progressive reduction of ambient light while several hundred swimmers are at sea. The schedule resolves it. During the record window — from 10:31:40 to approximately 11:30 — the eclipse remains in its early partial phase, and the reduction in illumination is modest. The deep darkening associated with annularity occurs from 12:05 onwards, by which time every swimmer is on the beach. The record window is thus deliberately positioned in the interval in which the astronomical condition is real but the light conditions remain fully safe for mass open water participation.

The Asociación Civil Open Water Río Negro undertakes to comply in full with any and all guidelines established by Guinness World Records for this attempt. The verification system set out below is offered as the applicants' proposed framework and will be adjusted in whatever manner Guinness World Records may direct.

9.1 Sporting verification

• Individual registration of all participants.
• Unique identification of each swimmer.
• Start and finish control at fixed, monitored points.
• Official synchronised timing, chip-based, referenced to the certified start instant.
• Continuous high-definition filming from the shore, from vessels and by drone.
• Supplementary photographic records.
• Qualified independent witnesses.
• Complete documentation of the event.
• Any further evidence Guinness World Records may deem necessary.

9.2 Astronomical verification — certification of the eclipse

While the start time of the solar eclipse is established beforehand using official data published by international astronomical bodies, the effective commencement of the record attempt will be certified in real time by an astronomer from Argentina's National Scientific and Technical Research Council (CONICET), who will act as an independent technical authority throughout the event.

This professional will verify, by direct observation and with the appropriate scientific instruments, the exact instant at which the partial solar eclipse becomes visible from the site of the event. Once the effective onset of the astronomical phenomenon has been confirmed, the astronomer will officially certify that moment and authorise the start of the swim.

Their technical certification, together with the audiovisual records, the official timing and the remaining documentation of the event, will form part of the evidence submitted to Guinness World Records to attest that the attempt began precisely with the onset of the solar eclipse as observed from the venue.

9.3 The evidence chain

The applicants wish to make clear that they are not seeking a commemorative entry attaching to a single event in a single country. They are seeking a title that will outlive the event that inaugurates it.

10.1 Predictability as the foundation of comparability

Solar eclipses are astronomical phenomena of perfect predictability, recurring at intervals in different regions of the planet, and computed decades ahead with a precision unmatched by any other natural event that could serve as a boundary condition for a sporting record. This is what makes the proposed title standardisable in a way that records dependent on weather, tide alone, or seasonal conditions can never be.

Every future organiser knows, today, exactly when and where the next opportunities will fall. The eclipse calendar is, in effect, the fixture list of this record.

10.2 The structure of a future series

Because the trigger is astronomical rather than local, the record can be contested wherever the shadow of the Moon crosses swimmable coastal water. The applicants anticipate, and actively wish to encourage, a succession of attempts by other organisations in other countries, each seeking to bring a greater number of swimmers safely across a course inside the same astronomically-defined window.

This structure is deliberate. The elements that must be identical between attempts, in order that the counts be comparable, are fixed by the title. The elements that must vary, in order that the record be safely attemptable in different seas and climates, are left to the organiser under the same body of open water guidance that already governs mass-participation swimming worldwide.

10.3 Value beyond sport

The title further carries considerable value for scientific outreach and education. It promotes a sporting event intimately bound to an astronomical phenomenon of international significance, and fosters a genuine meeting of science, sport, tourism and community. Each participant receives certified viewing glasses; each is briefed on the phenomenon; each leaves the beach having experienced an eclipse not as a distant spectacle but as the governing condition of their own physical effort. Few sporting formats carry so direct an educational dividend.

OWeclipse 2027 enjoys the backing of public institutions and leading companies of the region, which accompany an event of international projection combining sport, astrotourism and the promotion of Patagonia. The authorities and government bodies of the province are further called upon to join the project in the following areas:

• Safety and traffic: coordination with the Naval Prefecture, lifeguard services and local security forces.
• Health logistics: provision of medical personnel and ambulances on the beach.
• Official dissemination: inclusion of the event in the official calendars of tourism, sport and astrotourism.

11.1 Prizes, categories and the swimmer's kit

The competitive structure of the event is set out below. It is recorded here for completeness; it does not bear upon the record count, which is a simple tally of valid finishers.

• Official OWeclipse event shirt.
• Certified glasses for safe observation of the eclipse.
• Finisher medal for all who complete the crossing.

We respectfully request that Guinness World Records assess this project and determine whether the proposed title — Most people to complete an open water swim during a solar eclipse — meets the conditions necessary to be incorporated as a new official title, recognised internationally and open to attempt by organisations anywhere in the world.

Should it be deemed suitable, we should be grateful to receive the specific guidelines, measurement criteria, evidence requirements and any other rules necessary to organise the attempt of 6 February 2027 in accordance with the standards established by your organisation. The applicants undertake, without reservation, to adapt every aspect of the event — course, timing, verification, documentation — to whatever form Guinness World Records may specify.

We thank you sincerely for the time devoted to considering this project and remain at your disposal to provide any further information, documentation or clarification that may be required.