Geminids from Rio de Janeiro in 2026

Geminids from Rio de Janeiro: the short answer

Rio de Janeiro is at 22.9°S and 12 m, which puts the Geminids radiant 34.8° up at culmination (01:55 local time) on the night of maximum, 14 December 2026. Peak activity is 10:41, the rate on this city's own measured sky tops out at 7.8 an hour, and 23:00–04:00 is the stretch to be outside.

That makes the Geminids the strongest of the twelve annual showers from Rio de Janeiro in 2026, ahead of the Perseids at 2.1 an hour.

The radiant track over this city

Gemini carries the radiant. From Rio de Janeiro it clears the horizon at 20:57 on a bearing of 54° (NE), reaches 34.8° at 01:55 in the north, and drops back below the horizon at 06:54. Within the observing window it peaks at 34.8°.

When it gets dark here

The dark hours here run 19:59 to 03:34 — 7 h 35 min of astronomical night, bracketed by sunset at 18:32 and sunrise at 05:01. Civil twilight ends at 18:57; anything earlier than that is wasted effort.

Local solar midnight, the true middle of the night, falls at 23:47 here rather than at 00:00: America/Sao_Paulo runs 7 minutes behind mean solar time at 43.18°W. That offset is why the best hour on this page is not the hour you would guess from the clock.

What the Moon does here

The Moon is 22% lit and out of the way for 6 of the 10 sampled dark hours. Moonrise 09:33. Moonset 22:05. At the best hour it is 44.4° below the horizon, and the limiting magnitude works out at 4.00.

Why 8 an hour and not 150

The published ZHR of 150 assumes the radiant overhead and a sky at limiting magnitude 6.5. Here the radiant reaches 34.8° inside the dark window and the limiting magnitude at the best hour is 4.00, which with r = 2.6 gives 7.8 an hour. Entry speed is 33.8 km/s.

Hour by hour the modelled rate runs from 0.0 at 19:00 (radiant -23.3°) to 1.4 at 04:00 (radiant 27.3°), peaking at 7.8. That spread across 10 hours is why a "what time" answer beats a "how many" answer.

The stream comes from Minor planet (3200) Phaethon and is listed as active 4 December to 20 December, so 14 December 2026 is the best night from Rio de Janeiro rather than the only one.

Watching from around Rio de Janeiro

Rio de Janeiro is the 44th largest of the 300 cities covered here, with a population of 6.75 million at 12 m above sea level. The nearest other cities on the site are Belo Horizonte (341 km NNW), São Paulo (360 km WSW), Curitiba (678 km WSW) — close enough that the radiant altitudes barely change, far enough that sunset and moonrise do.

What this page does not know

Rates on this page are computed against this city's own measured sky brightness, derived from satellite night-lights data. That is a calculated brightness for the point directly overhead, not a survey of your street: a park on the edge of town and a lit car park in the centre share the same figure here and will not look the same. It is also zenith-only, while the Bortle scale describes the whole sky from horizon to horizon.

Cloud cover is a forecast, not a constant, so it is resolved when you load the tonight card and is deliberately absent from this prerendered page — the hourly table shows "unavailable" rather than assuming clear skies. Meteor outbursts, local terrain and building horizons are not modelled.

A single observer with an unobstructed horizon typically records 30–50% below the ideal-sky figure. Give your eyes twenty minutes to adapt, keep bright screens away, look about halfway up the sky rather than straight at the radiant, and count for a full hour before judging a shower.