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Meteor Showers

Why will you see fewer meteors than the forecast promises?

Why a shower's meteors all fly from one point, why the count is never the brochure's, and how to watch one — on the Geminids' peak night.

You’ll be able to find a shower’s radiant and set out to watch it at the right hour.

8 steps · about 6 min

Where and which night

Working out when this is best placed from where you are…

Where

Which night

Date

Time

Kept for this guide only, until you change it here — your map settings, and every other guide, stay as they are.

Print, play outside or present

Present on a big screen

Scan with a phone's camera, or open

Sources

International Meteor Organization — Meteor Shower Calendar and working list: the Geminids' peak, ZHR, radiant and 35 km/s entry speed
IMO — the zenithal hourly rate and its correction for radiant height and limiting magnitude, which this page's chart inverts
NASA Science: Geminids — debris of the asteroid 3200 Phaethon
NASA Science: Meteors and Meteorites — grains, most smaller than sand, burning up high in the atmosphere
Hecht, Haig & Chase, J. Gen. Physiol. 20, 831 (1937) — the rods' dark adaptation over twenty to thirty minutes

← GUIDES

More below ↓

With a keyboard, focus the sky, aim it with the up and down arrow keys, and press Enter to drop the pin at the centre of the view; or press Show me.

You are here

Settings

Screen

Night mode Turns every page red, to keep your eyes adjusted to the dark.

High contrast Bolder constellation lines, larger and brighter names on the sky, and stronger text and edges everywhere. Starts on if your device asks for more contrast.

Reduce motion The camera cuts to where it is going instead of flying there, and panels and sheets appear without sliding. Starts on if your device asks for less motion.

Battery saver Draws the sky thirty times a second at most: smoothness traded for battery.

Night brightness Dims the screen below your phone’s lowest setting, down to a fifth, while night mode is on.

Clock and voice

Clock How every time is written. Until you choose, your language’s own clock decides.

D describes What D says about the view on the sky: one sentence, or in full with the field, the constellation and five names.

Sounds Quiet tones as you use the map: a tick as you drag the clock past a mark or dusk, a chime for the star you pick — higher for hotter stars — and a low swell while a figure is out of the dome. Made in your browser, and off until you turn them on.

All settings and your progress

A meteor is a grain of dust, most smaller than sand, burning up about 100 km overhead at 35 km/s. Tonight, 14 December, is the Geminids' peak. The arrows are streaks like theirs. Trace them back before you guess.

Out here every long streak points back the same way. Follow the dashed lines to where they meet: the shower's , beside Castor and Pollux in Gemini, which names the shower.

Why one point? The grains share one orbit, so they hit the air on parallel tracks, which fan out from one vanishing point, like rails. They are shed by 3200 Phaethon — an asteroid, the exception to Comets' rule that showers are old comets' trails.

Run the night; watch the radiant's height.

The night as a graph. The rule is the ZHR, 150 an hour: a perfect sky, radiant overhead. Dashed: a perfect sky, radiant where it is. Solid: a suburb, 5, with the Moon. Dotted: a city, where most of us watch.

How to watch: lie back and look about 40°, two spread hands, from the radiant, not at it. Meteors near the ring come head-on and are short; out here they are long. No telescope — they are everywhere, and a dark site beats any gear.

Then wait an hour: eyes take twenty to thirty minutes to adapt, so use a red light. Wear layers, bring a reclining chair. Next: the Quadrantids (4 January), Perseids (12 August) and Orionids (21 October), Halley's dust.

The whole shower on one sky: where the streaks come from, and where to look.

Streaks trace back to one point, the radiant
The higher it climbs, the more you count
Look 40° from it, and give it an hour