NASA’s Zombie Satellite Sends Shockwaves After Decades of Silence

A NASA satellite, dormant since 1967, has stirred back to life, emitting a perplexing signal that has scientists scrambling for answers. The resurgence of this “zombie satellite” raises critical questions about space junk and the long-term behavior of inactive technology orbiting Earth.

Unexpected Signal Detection

In June 2024, astronomers were startled by an unusually potent radio signal, not from a distant galaxy, but traced back to the Milky Way. Further investigation pinpointed the source as Relay 2, a NASA satellite launched in 1964. It had been out of commission for nearly six decades.

The Australian Square Kilometer Array Pathfinder (Askap) picked up the signal while scanning for Fast Radio Bursts (FRB), typically originating from far-off galaxies. This unexpected discovery presents a novel puzzle for space researchers.

Possible Explanations for the Anomaly

Clancy James, lead author of the study and professor at Curtin University’s Institute of Radio Astronomy in Australia, described the radio pulse as exceptionally strong, “brighter than anything in the sky at that time.” The fleeting 30-nanosecond burst rules out any deliberate transmission.

Researchers propose two primary hypotheses to explain the phenomenon. One involves a micrometeoroid collision, where high-speed cosmic dust impacts the satellite, generating plasma clouds and releasing radio waves. The other suggests an electrostatic discharge (ESD), where accumulated electrical charge on the old satellite is suddenly released, producing a strong radio pulse.

Relay 2’s Historical Significance

Despite its period of inactivity, Relay 2 was an important component of NASA’s early communication efforts. However, transponder damage only three years after launch curtailed its ability to transmit signals. Now, its brief reemergence has reignited interest in its legacy and potential insights it can offer.

Zombie Satellites: A Growing Concern

The term “Zombie Satellite” refers to satellites that unexpectedly reactivate after years of dormancy due to orbit loss, power failure, or technical issues. These satellites, once considered defunct, can suddenly transmit signals or even become partially functional again.

One notable instance involved Galaxy 15, an Intelsat telecommunications satellite that experienced a slide in 2005. It lost contact in April 2010, but its system remained active. In December 2010, Galaxy 15 automatically rebooted, and Intelsat eventually restored it to its original position.

Amsat-Oscar 7: A Record-Breaking Revival

Amsat-Oscar 7, an amateur radio satellite, holds the record for the longest period of dormancy before reactivation. It ceased operations in 1981 due to battery failure but resurfaced on June 21, 2002, after 21 years, resuming active communication.

Future Implications and Protection Strategies

Even though Relay 2 isn’t fully operational, this discovery is invaluable for future satellite protection. Understanding the causes behind the signal could mitigate similar disturbances and enhance satellite safety. Space debris, including inactive satellites, poses a significant threat to active spacecraft. As of early 2024, the European Space Agency (ESA) estimates there are over 36,500 objects larger than 10 cm in orbit (ESA), underscoring the urgency of addressing space debris and satellite anomalies.

Ultimately, the case of the NASA zombie satellite highlights the unpredictable nature of space and the importance of ongoing research to safeguard our orbital infrastructure.