Southern delta-Aquariids from Sydney in 2026

Southern delta-Aquariids from Sydney: the short answer

The Southern delta-Aquariids peaks at 23:23 local time on 31 July 2026 over Sydney, New South Wales. Culmination is 02:03 at 72.1° — 95% of the rate a zenith radiant would give — so the ceiling here is 0.5 an hour, not worth the sleep.

That ranks it 8th of twelve from Sydney this year, behind the Geminids (9.0/h) and the Orionids (1.9/h).

The radiant track over this city

At 33.9°S a declination-−16.1° radiant traces an arc from 19:19 to 08:47, topping out at 72.1° at 02:03 bearing 0°. Inside the dark window it only manages 72.1°, and that lower figure is the one the rates are built from. The radiant currently lies in Aquarius.

When it gets dark here

The dark hours here run 18:40 to 05:21 — 10 h 41 min of astronomical night, bracketed by sunset at 17:14 and sunrise at 06:47. Civil twilight ends at 17:41; anything earlier than that is wasted effort.

Local solar midnight, the true middle of the night, falls at 00:01 here rather than at 00:00: Australia/Sydney runs 5 minutes behind mean solar time at 151.21°E. 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

Moonlight is the limiting factor on this night from Sydney. The Moon is 96% lit and only 1 of 13 sampled hours are moon-free. Moonrise 18:47. Moonset 08:08. At the best hour it stands 37.5° above the horizon, 9° from the radiant, pulling the limiting magnitude down to 3.34.

Why 1 an hour and not 25

The published ZHR of 25 assumes the radiant overhead and a sky at limiting magnitude 6.5. Here the radiant reaches 72.1° inside the dark window and the limiting magnitude at the best hour is 3.34, which with r = 3.2 gives 0.5 an hour. Entry speed is 40.6 km/s.

Hour by hour the modelled rate runs from 0.0 at 18:00 (radiant -14.9°) to 0.0 at 06:00 (radiant 34.2°), peaking at 0.5. That spread across 13 hours is why a "what time" answer beats a "how many" answer.

The stream comes from Comet 96P/Machholz and is listed as active 12 July to 23 August, so 31 July 2026 is the best night from Sydney rather than the only one.

Watching from around Sydney

Sydney, New South Wales is the 48th largest of the 300 cities covered here, with a population of 5.64 million at 58 m above sea level. The nearest other cities on the site are Melbourne (713 km SW), Brisbane (733 km NNE), Adelaide (1162 km W) — 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.