New Horizons begins record hibernation in Kuiper Belt
by Clarence Oxford
Los Angeles CA (SPX) Aug 22, 2025
At 4:12 a.m. EDT on Aug. 7, mission controllers at Johns Hopkins Applied Physics Laboratory confirmed that New Horizons had safely entered hibernation mode. The spacecraft, operating more than 5.7 billion miles (9.2 billion kilometers) from Earth in the Kuiper Belt, acted on commands uploaded July 23. The confirmation signal required 8 hours and 31 minutes to reach Earth, traveling at light speed via NASA's Goldstone Deep Space Network station in California.

This marks the start of the longest hibernation in the spacecraft's history, expected to last until late June 2026, pending budget approval. The period will surpass the previous record of 273 days set between June 2022 and March 2023.

Although in hibernation, New Horizons will continue to collect science data around the clock using three instruments to monitor charged particles in the outer heliosphere and dust in the Kuiper Belt. These measurements will be stored and sent back once the spacecraft reactivates.

"Even when our spacecraft sleeps, round-the-clock science data collection never stops," said Alan Stern, New Horizons Principal Investigator at the Southwest Research Institute in Boulder, Colorado.

Hibernation reduces operating costs and extends spacecraft life. While in this mode, New Horizons spins in a stable configuration with most systems powered down. Its onboard computer oversees health checks and transmits a weekly beacon tone through the Deep Space Network to confirm operational status.

Since its launch in 2006, the spacecraft has entered hibernation 23 times, ranging from a few days to many months.

Related Links
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