In 1965, MIT's LES-1 failed to reach its planned orbit and fell silent in 1967; 45 years later, the zombie satellite unexpectedly began transmitting again

An artifact from the JFK-era space program has been contacting Earth for a decade now, without any clear reason known to anyone. Phil Williams, a British amateur radio enthusiast, was tuning in on a frequency outside the VHF band while listening to ham radio in his North Cornwall home in December 2012 when he detected something strange: an intermittent, ghostly pulse which repeated every four seconds on 237 MHz. He worked backwards and found it was being broadcast by one of the satellites the US Air Force and MIT had previously deemed space junk in 1967.

According to a 2024 MIT Lincoln Laboratory report, the LES-1 satellite had been turned off at the end of its planned mission almost 50 years ago, and no one, not even its designers, was expecting any signals from it now. This isn't found footage from a horror film. Not only is it a true, documented story of one of the earliest experimental satellites in America refusing to remain dead, but it's also a tale of the trash that humans have left orbiting above us.

The confusing satellite story


The first in a series of satellites built by MIT's Lincoln Laboratory for military communications technology was LES-1. It was launched from Cape Canaveral on Feb. 11, 1965, designed to be used for high-frequency radio transmission for the Pentagon's satellite network. However, it got stuck in the wrong orbit at the time of its launch, taking a circular path rather than the higher ellipse initially planned by the engineers. Its near-identical twin, LES-2, made its way to the correct orbit in the next few months, but LES-1 got little chance to do its job well. Its mission ended by 1967; the transmitter went silent, and it was hoped that it would ‘drift mute' in space for millennia.

This is what made December 2012 so strange. Other amateur radio operators in Brazil and Germany confirmed Williams' discovery in just a few days, and ever since, the signal has been coming and going every 4 seconds as the satellite tumbles end over end. The most plausible theory, according to the team at MIT's Lincoln Laboratory, is pretty plain: the degradation of batteries and circuitry over the years probably led to a short circuit that lets power from the solar panels of LES-1 leak directly into the old transmitter, effectively shorting it out to life every time sunlight hits the panels. No ghost in the machine, only corroded hardware acting in an unusual manner that no one expected.

Why a dead satellite still matters

The craft has been included as one of a small but growing group of "zombie satellites," meaning spacecraft whose operators have declared dead but are subsequently found to be still alive or "still drifting/transmitting.” According to a 2017 NOAA article, these whimsical resurrections, of course, are a quirky footnote now, but they highlight a true problem: after launching, it's hard to tell what a satellite is doing after it launches, even for decades, and the number of satellites in the sky rises with as many as we stop actively managing.

The key takeaways

It's the people who discovered this that makes the story really interesting: a guy, with a radio in his house, not a government tracking station, not a room full of engineers. Spaceflight-history studies from Drew Ex Machina, based on the 1967 engineering paper titled “Lincoln experimental satellite program - LES-1, -2, -3, -4,” describing the LES project in the Journal of Spacecraft and Rockets, explain just how forgotten LES-1 was until Williams found it. In an age when multi-billion dollar organizations dominate all headlines related to space, there's a nice irony in the fact that all that technology was beaten out by a backyard antenna.

LES-1 is not sending hidden signals or planning its return. It's just an old and damaged device malfunctioning due to solar energy 60 years after launch. At the same time, it's a good example of how the concept of being "dead" in space might be rather vague, and how the objects we put there do not necessarily stay silent.