Why Use a Comet at All?
Strategically, a comet offers several advantages to a civilization that wants to communicate without revealing its location:
- Stealth and deniability: Appears as a natural body.
- Durability: Can travel for eons through interstellar space.
- Universality: Any intelligent species with astronomy will study comets.
- Self-powering: Solar energy triggers emissions automatically near stars.
- Symbolism: A comet is a literal messenger — its name derives from “long-haired star,” and its periodic return makes it ideal for time-coded communication.
It’s the ultimate low-energy, high-longevity interstellar post card.
Meanwhile, back here on Earth, the SETI Institute and other facilities are calibrating receivers around the 1420–1720 MHz window to search for repeatable patterns or mathematical sequences.
Researchers expect to collect the next round of spectra in mid-December as 3I/ATLAS makes its closest approach to Earth on December 19, 2025. Any repetition of narrow-band activity at the same frequencies could confirm a non-random source. Juno’s March 2026 flyby will then offer an independent space-based check. Results from both campaigns are expected by mid-2026.
