Random Daily App

An interactive reconstruction of GW170817

The sky arrived
at three times.

A ripple passed through Earth. Livingston, Hanford, and Virgo heard it—each clock preserving a slightly different arrival.

Slide each pale chirp onto its fixed reference tick. The sky will answer only when all three clocks agree.

Detector records

Correct the clocks

window ±24 ms

L1

Livingston

Louisiana, USA

−13.0 ms

The chirp is early

H1

Hanford

Washington, USA

+15.0 ms

The chirp is late

V1

Virgo

Cascina, Italy

−4.0 ms

The chirp is early

Focus a trace and use arrow keys for half-millisecond steps.

Southern sky projection

Where did it come from?

0% 0%
A simplified sky-localization map Three broad uncertainty bands cross a star field. Aligning all detector traces narrows them to the host galaxy NGC 4993.

The clocks agree

NGC 4993
Hydra · 130 million light-years

0 of 3 clocks centered. The wide bands are places the source could still be.

The last milliseconds were ours.
The previous 130 million years were the journey.

12:41:04 UTC
spacetime reaches Earth

+1.7 seconds
gamma rays follow

This is a simplified visual reconstruction—not the real parameter-estimation pipeline.