The Last Arecibo Message: A Modern Interstellar Note Inviting Collaboration to Teegarden’s Star

The Last Arecibo Message: A Modern Interstellar Note Inviting Collaboration to Teegarden’s Star

Boriken Voyagers team members Kelby D. Palencia-Torres, César F. Quiñones-Martínez, Javier A. García Sepúlveda, Luis R. Rivera Gabriel, Lizmarie Mateo Roubert, Germán Vázquez Pérez, and Abel Méndez reframe the 1974 Arecibo broadcast as a modern interstellar note inviting collaboration, select Teegarden’s Star with Teegarden b and c as proximity- and habitability-enhanced targets (Earth Similarity Index around 0.90 and 0.88), propose an S-band beacon at 2370–2390 MHz with 20 Hz modulations delivering a 5,402-bit main message in about 4.5 minutes (plus prephase and endphase for ~5.5 minutes total) and up to 27 repeats in a 2.5-hour window, estimate energy use of roughly 11 gallons per repetition and ~298 gallons for 27 repeats, encode a three-part message and a seven-section main body (numbers 1–10, arithmetic, constants, Milky Way scale, Solar System and major elements, Earth–Moon, and a more detailed human representation) for universal decoding with minimal biology, acknowledge SETI/METI debates and risks while urging caution and sufficiently capable receivers, note Teegarden b’s habitability could be challenged by M-dwarf activity, and, though not transmitted due to the Arecibo collapse, honor the mission’s legacy and envision future interstellar dialogue beginning with “we are ready to explore the universe together.”