Lost Moon Found: The Satellite That Came Back to Life


The late 1950s and early 1960s were a tumultuous time in world history. The Cold War between the East and the West was in full-swing, driving the new fields of nuclear weapons and space exploration and giving the period its dual monikers of “Atomic Age” and “Space Age.”

Changes in these fields often went hand in glove, with developments in one requiring responses in the other. In 1958, the US conducted nuclear tests in the Pacific that effectively destroyed the ionosphere over the test site and shut down high-frequency communications to places like Hawaii and New Zealand. The strategic implications of this were clear, and the US began looking for ways for the military to reduce its reliance on HF communications and ionospheric skip by using space-based assets to communicate at much higher frequencies.

Millions of Satellites: Project West Ford needles. Source: Gunter's Space Page
Millions of Satellites: Project West Ford’s needles. Source: Gunter’s Space Page

MIT’s Lincoln Laboratory was given the job of exploring space communications in the super-high frequency (SHF) band. The first idea borne of Project West Ford was to disperse half a billion 1.8 cm long #53 AWG copper needles in orbit to act as an artificial ionosphere capable of reflecting SHF signals. It worked well enough to allow voice communications between Massachusetts and California on 8 GHz, but the idea was shelved in a nod to space hygiene. Most of the needles had deorbited by 1966, but today there are still 38 clumps of needles in orbit that failed to properly disperse.

LES 1 mounted on its failed kicker motor. Source: Lincoln Laboratoiy
LES 1 mounted on its failed kicker motor. Source: Lincoln Laboratory

Lincoln scientists turned their attention to active SHF satellite communications and designed the “LES” series, for Lincoln Experimental Satellites. LES 1 was a tiny, 31 kg package that was designed to use Project West Ford’s SHF ground stations. It and its twin LES 2 each carried an X-band transponder and an 8-horn antenna along with a 237 MHz downlink, solar panels, and batteries, and were designed to study not only space communications but also to practice launching and maneuvering satellites.

LES 1 was launched from Cape Canaveral in February of 1965, but never achieved its intended orbit due to a wiring error which prevented the kicker engine from firing. LES 1 was crippled, languishing unused in a nearly circular orbit while its twin and siblings LES 3 through 9 went on to complete successful missions the contributed to satellite communications and control technology. Its 237 MHz signal stayed active, though, and continued transmitting until 1967 when something finally gave out.

LES 1 tumbled silently in orbit for the next 46 years as the Space Age roared around it. Men went to the moon and back, probes set off to explore the solar system and beyond, and bigger, more sophisticated satellites crowded into orbit with it. LES 1 would have joined the ranks of orbital flotsam if not for a strange confluence of factors that led to its signal being reacquired in 2013. Cornish amateur radio astronomer [Phil Williams (G3YPQ)] detected a faint but repeatable signal on 237 MHz. After a little sleuthing he identified it as the long-lost LES 1; other radio hobbyists have since eavesdropped on the signal from LES 1 and confirmed his findings. The working theory is that at some point in the last four decades, the satellite’s battery degraded in such a way that the solar panels were able to power the transmitter directly. The evidence for this is based on the slow warble in the signal as the satellite tumbles, exposing the solar panels to the sun at four-second intervals.

Of course there’s no way to know what happened to LES 1 for sure, but the fact that it was built robustly enough to still be operating after nearly half a century in space is a testament to the engineering team that designed and built it. LES 1 may have been a failed mission, but it was certainly built for the long haul.

[via The Vintage News]



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