How NASA's 'Big Bang' maneuver saved Voyager 2's interstellar science

The central trick: many of Voyager 2's heaters were designed to keep entire subsystems warm, including non-essential ones. By turning those off and switching to lower-power heater alternatives for only the critical components, engineers freed up enough power to avoid shutting down another science instrument. Without the fix, the mission would have been forced to turn off a third instrument before the end of 2026, leaving just two of three remaining instruments operational .

The result: Voyager 2 can now keep all three of its remaining science instruments running for at least one more year — through roughly mid-2027 or longer — delaying further instrument shutdowns .

Which scientific instruments were preserved

Voyager 2 had already lost several instruments to prior power-saving shutdowns. As of mid-2026, the three instruments preserved by the Big Bang are:

1. Magnetometer (MAG) — measures interstellar magnetic fields
2. Plasma Wave Subsystem (PWS) — detects plasma waves in interstellar space
3. Cosmic Ray Subsystem (CRS) — measures cosmic ray particles from outside the solar system

These three make up humanity's only in-situ sensor network operating in interstellar space. There is no replacement mission currently funded or planned .

The risks involved

This was a high-stakes, single-shot procedure with no take-backs . Key risks included:

• Irreversible commands with a 17-hour light-speed delay. The command signal took about 17 hours to reach Voyager 2, and any confirmation of success took another 17 hours to return. Engineers could not intervene in real time if something went wrong .
• Thermal risk. Turning off heaters on a 49-year-old spacecraft in interstellar space could cause critical components to freeze and fail permanently. If the lower-power replacements did not keep temperatures within safe margins, systems could be lost .
• Fault protection trigger risk. If the spacecraft's onboard fault protection routines detected any anomaly during the reconfiguration, they could have autonomously shut down more systems than intended, accelerating the mission's end .

The team spent months modeling and testing the sequence before sending the final command . The Big Bang fix was implemented on July 9, turning off two dedicated heaters and a digital tape recorder .

Next steps for Voyager 1

Voyager 1 is already on a similar path. On April 17, 2026, JPL engineers shut down Voyager 1's Low-Energy Charged Particle (LECP) instrument to buy about a year of breathing room — reducing the spacecraft to three operating instruments (magnetometer, plasma wave subsystem, and cosmic ray subsystem) .

The Big Bang concept was originally designed as a fix for both Voyagers . Now that the procedure has been proven successful on Voyager 2, NASA plans to execute a similar Big Bang reconfiguration on Voyager 1 . The timeline:

• Voyager 1's LECP shutdown in April 2026 gave engineers roughly one year to finalize and execute the same kind of heater-swap power maneuver .
• The key difference: Voyager 1's reduced power margin has been tighter and more unpredictable than Voyager 2's, so engineers may need to adapt the sequence and do additional modeling .
• No exact date has been announced yet, but NASA has stated the Big Bang fix is designed for both spacecraft, and Voyager 1's reconfiguration is expected to follow .

If successful, Voyager 1 would also keep its three remaining instruments operating for at least another year beyond the current timeline, potentially pushing both missions deeper into the 2030s .