NASA’s New Horizons spacecraft has awakened from a 321-day hibernation period, resuming active operations at a distance of about 9.5 billion kilometers from Earth. Flight controllers at the Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland, confirmed the successful wake-up on June 23, 2026, after executing stored commands sent to the probe’s main computer last July. Due to the immense distance, the radio signals carrying the confirmation took approximately 8 hours and 52 minutes to reach the Mission Operations Center via NASA’s Deep Space Network station near Madrid, Spain.
The hibernation period began on August 7, 2025, as part of standard mission procedures to conserve resources during long stretches of interplanetary cruising. While in this low-power state, the spacecraft continued to collect and store data around the clock using three instruments: the Solar Wind at Pluto (SWAP) and Pluto Energetic Particle Spectrometer Science Investigation (PEPSSI) plasma sensors, and the Venetia Burney Student Dust Counter (SDC). During hibernation, New Horizons sent weekly status reports to Earth. Mission Operations Manager Alice Bowman noted that every report during this period was marked “green,” indicating that all systems were functioning optimally week after week.
Now that New Horizons has returned to active mode, the mission team will begin downloading health and safety data from the spacecraft, followed by the scientific data collected by the three instruments during hibernation. Over the next three weeks, the Alice ultraviolet spectrograph will analyze the distribution of hydrogen gas in the outer heliosphere, while SWAP, PEPSSI, and SDC will continue their real-time measurements. Engineers are also completing software updates to the ground system to streamline operations, with tests already underway and expected to continue throughout the year.
New Horizons launched in January 2006 on the fastest trajectory ever recorded for a spacecraft at that time. It flew by Jupiter in February 2007, providing stunning views of the gas giant and its moons. The probe made history in July 2015 with the first exploration of the Pluto system, followed by a flyby of the Kuiper Belt object Arrokoth in January 2019. Since then, it has conducted unique studies of the Sun’s outer heliosphere and dozens of other objects in that remote region. The spacecraft is now navigating autonomously using updated software designed to operate at ever-greater distances from the Sun, optimizing power reduction and managing the increasing travel time of radio signals.
The wake-up marks a new phase for the mission, which continues to push the boundaries of deep-space exploration. With its instruments operational and data flowing back to Earth, New Horizons is poised to provide further insights into the environment at the edge of the solar system. The mission team remains focused on maximizing the scientific return from this distant outpost, as the spacecraft travels farther into the unknown.