6 February 2027: a seven-minute ring of fire over Argentina and Uruguay

On 26 February 2017, more than 2,000 people lined the seafront in Camarones, a small fishing town on the coast of Chubut. Above them, the Moon left only a thin bright ring of the Sun, for 54 seconds. “Fue un espectáculo precioso,” Adriana, who had driven down from Trelew, told a reporter: it was a beautiful show.

Ten years later, Patagonia gets a ring that lasts about eight times as long. On Saturday 6 February 2027, an annular eclipse crosses southern Chile, Argentina and Uruguay around midday, and on the Río Negro coast and at Mar del Plata the ring holds for about seven and a half minutes.

Why this ring lasts so long

An annular eclipse happens when the Moon passes straight in front of the Sun but looks slightly too small to cover it. A bright ring of sunlight stays visible all around its edge, which is why people call it a ring of fire.

How long the ring lasts depends on two distances. On 6 February 2027 the Moon is close to its farthest point from the Earth, so it looks smaller than usual. The Earth passed its closest point to the Sun only a month earlier, which makes the Sun look slightly bigger. A bigger gap between the two sizes means a longer ring, and at sea it lasts up to 7 minutes and 51 seconds.

The Moon covers about 86% of the Sun at the peak. Sunlight dims and shadows sharpen, but the sky never turns dark, and the corona never appears. For those you need a total eclipse, like the one on 2 August 2027.

From the Andes to the Atlantic

The ring first reaches land on Chiloé and the Chilean mainland around Chaitén and Futaleufú, shortly before noon. It crosses the Andes into Argentina near Esquel and Trevelin, where the ring lasts about seven and a half minutes. From the mountains the path runs east across the Patagonian steppe and reaches the sea at Las Grutas, on the San Matías Gulf.

From Viedma the path heads north-east along the coast of Buenos Aires province. Bahía Blanca lies close to its northern edge, with less than four minutes. Mar del Plata, Argentina’s main beach city, is near the centre line, with about seven and a half minutes at 12:24 pm.

Across the River Plate estuary, the path covers the Atlantic coast of Uruguay. Punta del Este gets more than five minutes, and La Paloma and Cabo Polonio, farther east, a little over six. The ring just catches the southern tip of Brazil around Chuí, then heads out over the South Atlantic.

Carnival weekend

The eclipse falls on the first day of Carnival in Brazil, and Monday 8 and Tuesday 9 February are public holidays in Uruguay. It is also the height of the southern summer holidays, when Argentine, Uruguayan and Brazilian families crowd the beaches from Mar del Plata to Punta del Este. Accommodation on the coast is scarce every February, and eclipse visitors will add to the crowds in 2027.

Where to see the ring of fire on 6 February 2027

Weather figures below are for early February. They come from Jay Anderson, a Canadian meteorologist who has written the weather forecasts for NASA’s eclipse bulletins for decades, and are based on satellite cloud records.

• The Río Negro coast, around Las Grutas and San Antonio Oeste More than seven minutes near the centre line, and the best odds in South America: about 72% of possible sunshine, with a clear view in 20 of the last 23 years.
• Esquel and Trevelin About seven and a half minutes in the Andes foothills, with around 64% sunshine and the Sun about 52 degrees up. The town has an airport and sits on Ruta 40.
• Bahía Blanca Less than four minutes near the edge of the path, but a large city with an airport and 68% sunshine. Anderson calls it the best choice for anyone who wants to watch from the edge of the path.
• Mar del Plata About seven and a half minutes in a big resort city, with sunshine around 60% of the time.
• The Uruguayan coast Five to six minutes at Punta del Este, La Paloma and Cabo Polonio, with cloud about half the time.
• Coastal Ghana and Togo More than five minutes at Cape Coast and Accra, with the Sun only 4 to 5 degrees above the sea. Cloud spoiled the view in only one year out of 23, but moderate or heavy Saharan dust hit 10 years out of 24 and can hide a Sun that low.

Sunset in West Africa

After crossing the South Atlantic, the shadow reaches the Gulf of Guinea in the late afternoon. The ring forms over Cape Coast and Accra at about 5:49 pm, with the Sun low over the water, about 20 minutes before sunset. Ghana last saw the Moon’s shadow on 29 March 2006, when a total eclipse crossed the same coast.

Six months later, on 2 August 2027, a total eclipse with up to 6 minutes and 23 seconds of totality crosses southern Spain, North Africa and Egypt.