Stille

{A radio observatory
inside a 40 km quiet zone}

{Tuned to/}
81.500 MHz · Stille

{Sound}

CP 1919

Pulsar
PSR B1919+21

The first pulsar anyone ever heard. For a few weeks in 1967 it was filed as LGM-1: little green men.

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← All stations {Each line = one pulse}
Catalogue
PSR B1919+21
Type
Pulsar
We listen at
81.500 MHz
Period
1.3373 s
Distance
≈ 2,300 light-years
Discovered
28 Nov 1967
By
Jocelyn Bell Burnell & Antony Hewish, Cambridge
Position
19h 21m 44.8s
+21° 53′ 02″
From Stilledal
Circumpolar. Never sets over Stilledal.

Jocelyn Bell Burnell found it as a quarter inch of scruff on a chart recorder: a signal that came back every 1.3373 seconds, more regular than any clock in the building.

It is a neutron star, a city-sized cinder of a dead sun, spinning. Each turn sweeps a beam across the Earth. We catch one click per turn, the way a ship catches a lighthouse.

Look closely at the stack and you will see the pulses wander inside their window, drifting left in small steps. Nobody has fully explained why.

{What it sounds like}

A slow knock, like someone patient at a door.

{Headphones help. The sound is synthesized from the real period and profile.}