            .-""""""-.
          .'          '.
         /   O    O     \
        :                :
        |                |
        : ',          ,' :
         \  '-......-'  /
          '.          .'
            '-......-'
               ||||
            ___||||___
           |  SIGNAL  |
           |  ══════  |
           |  ▓▓▓▓▓▓  |
           |__________|
          /____________\
    ~·~·~·~·~·~·~·~·~·~·~·~

📡 The Signal

Deep space transmissions decoded and interpreted

Today's Signal Decode Signal Catalog Signal Origins SETI History About

🌌 Signal Origins

Where do these transmissions come from?
A guide to natural and potentially artificial sources.

Natural Sources

Pulsars — Spinning neutron stars emitting lighthouse beams of radio waves
Quasars — Active galactic nuclei powered by supermassive black holes
Magnetars — Neutron stars with incredibly powerful magnetic fields
Masers — Cosmic microwave lasers from gas clouds around stars
Solar flares — Bursts from our own sun and other stars
Lightning — Electromagnetic pulses from planetary atmospheres
Auroras — Radio emissions from magnetic field interactions
Cosmic background — The echo of the Big Bang itself

Potentially Artificial Sources

Narrow-band signals — Nature rarely produces single-frequency transmissions
Modulated carriers — Information-bearing waves suggest intelligence
Mathematical patterns — Prime numbers, constants, or geometric sequences
Doppler shifts — Suggesting a source on a rotating planet
Repeating patterns — Too regular to be random, too complex to be natural
Technosignatures — Waste heat, laser pulses, or megastructure shadows

The Water Hole

Between 1420 MHz (hydrogen) and 1662 MHz (hydroxyl) lies the "water hole" — a quiet region of the spectrum where hydrogen and oxygen, the components of water, whisper. SETI scientists consider this the most likely frequency range for interstellar communication. Any civilization that understands chemistry would recognize this cosmic meeting place.