FM Signal From Jupiter's Moon Ganymede Discovered By NASA

Summary

January 13 2021: NASA's Juno space probe detected an FM Radio-band emission coming from Ganymede, the largest moon orbiting Jupiter.

Sadly, the broadcast is almost certainly just garbage caused by fluctuations in the magnetic field of Jupiter, not some sort of alien message.

Source

Bibliography

1. Original Article

Game and Story Use

• But it could be aliens if that's what fits your story! Von Neumann Probes scuttling about on the ice, or a crashed spaceship buried a few icy layers deep. Don't let realism get in the way of a good tale.
  • Could not be so much aliens as ancient astronauts - something left over from the last time we had a space programme…
• Ganymede's surface has grooves that run thousands of miles long, and may be places where tidal pressures crack the ice or cause water from below to vent. That makes them the likely place for anything interesting to be exposed, or buried.
• Below the ice is a sub-surface ocean, or possibly even multiple stacked oceans between layers of ice. If there's some sort of energy source down there, like geothermal vents or the like, then it's possible some sort of underwater biosphere could be there.
  • There could be some sort of extremophile microbe down there.
  • Less likely would be something akin to complex deep sea animal / aquatic animal life here on earth.
    • Crocodile Icefish may suggest biology that could theoretically live down there, without even having to dip into Hypothetical Types of Biochemistry if you'd rather not.
    • Creepy critters like Deep sea hatchetfish, wolf trap anglerfish, and starfish aliens may give you some crazy imagery ideas.
    • Some sort of spacewhale that communicates by Electro-Magnetic Frequency Modulation could be fun as well.