Voyager 1 reaches one light day from Earth on 18 November 2026, the first spacecraft ever to get that far. How do we still hear a 49-year-old probe with a transmitter of about 22 watts, almost 26 billion km away?
We follow one message home: the narrow beam, the nearly day-long trip at light speed, the giant Deep Space Network dishes that catch it, the two-day round trips behind every repair, and the power that runs down a little more each year.
0:00 One message home
0:49 Where is it right now?
1:53 How does 22 watts reach us?
2:50 What keeps it pointed at us?
3:40 What's left when it arrives?
4:50 Who's listening?
6:06 What if something breaks?
7:38 Where is the power going?
9:05 How long until it goes quiet?
What this film does and does not claim: the on-screen signal clock follows one representative message on 22 Oct 2026 (23 h 56 min one way, JPL Horizons); it is an estimate, not a tracked transmission. Voyager 1 reaches one light-day of DISTANCE on 18 Nov 2026 (NASA); the signal's own travel time passes 24 hours a few hours later. NASA's "20 billion times" watch comparison dates from Voyager 2's Neptune encounter in 1989; today's signal is fainter. The beam diagrams are illustrations, not to scale. The spacecraft photos show the 1976-77 proof test model, which did not fly. NASA gives no date for when Voyager 1 will fall silent.
Sources
- NASA, "Voyager 1: What Is a Light-Day" (2026) and Voyager mission status pages (instrument table, updated 17 Apr 2026)
- NASA Voyager blog: 15 Mar 2024 (memory readout decoded), 22 Apr 2024 (engineering data returns), 10 Sep 2024 (thruster swap), 28 Oct and 26 Nov 2024 (backup S-band transmitter), 5 Mar 2025, 14 May 2025 (thrusters revived; DSS-43), 17 Apr 2026 (power, LECP off), 4 Aug 2026
- NASA/JPL PIA17047 (22-watt transmitter, refrigerator-bulb comparison); PIA26147 (Madrid six-antenna array, 20 Apr 2024)
- Ludwig & Taylor, "Voyager Telecommunications", JPL DESCANSO (2002)
- NASA Radioisotope Power Systems: MHW-RTG, 158 W at launch
- JPL Horizons ephemeris for Voyager 1 (distance and light time, 22 Oct and 18 Nov 2026)
Visuals: NASA/JPL-Caltech (Voyager proof test model and build photos 1975-77, Goldstone, DSS-43 upgrade, the Voyager team 2024, RTG, illustrations PIA22915/PIA22921, artist's concept PIA26353), NASA/Canberra Deep Space Communication Complex (DSS-43), MDSCC/INTA Francisco "Paco" Moreno (Madrid array). Music is original. Data cards and the signal clock are original graphics.
Narration is a synthetic voice. Independent production, not affiliated with or endorsed by NASA or JPL.
If you could send Voyager 1 one last message, what would you say?
