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Have you ever wondered what Earth would be like if it had a big, gorgeous ring like Saturn's?
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Well, in the 1960s, we did almost put a ring on Earth.
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Starting in 1961, the US military tried to launch hundreds of millions of tiny copper
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needles into space to create a reliable boost for their communications systems.
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They called it Project West Ford.
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At the time, if the US wanted to send long-range messages to their allies on the other side
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of the Atlantic, they had two main options:
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They could send them through undersea cables, or by bouncing radio signals off of the ionosphere,
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a layer of the upper atmosphere that stretches from about 50-1000 kilometers up.
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The ionosphere is full of charged particles like ions and electrons, which means you can
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sometimes use it as a kind of long-range, signal-boosting antenna.
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When radio waves hit electrons in the ionosphere, they vibrate at the same frequency as the radio wave.
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And as they vibrate, they emit radio waves of their own, bouncing the signal back down to Earth.
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The problem was that neither of these approaches are fool-proof.
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Undersea cables can be sabotaged, and since this was the Cold War, sabotage was business as usual.
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And the ionosphere is really unpredictable.
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The number of electrons available to carry a signal changes with the seasons, solar weather,
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and plenty of other factors that we still don't understand.
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So, the US military wanted a system that was reliable and beyond sabotage.
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They decided that if the ionosphere wasn't reliable for sending messages, well, they'd
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just make something that was.
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And so Project West Ford was born.
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The idea was to launch 480 million copper needles into space where they would fill the
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orbit they were placed into, creating a ring.
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The needles were each 1.28 centimeters long, and about as thin as a human hair.
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During the testing phase, each of these copper needles would help boost the signal for a
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receiver dish in the town of Westford, Massachusetts.
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But eventually, other sites would be able to use the communications ring, too.
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The needles would work by acting as little dipole antennas.
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At its simplest, a dipole antenna is basically a wire that's exactly the right length to
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boost signals with a specific frequency.
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When you carefully match the signal to the antenna this way, it creates a standing wave,
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where the vibrations of the electrons in the needle bolster one another to produce a strong radio wave.
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That stronger radio wave can then be picked up by other needles, or by stations on the ground.
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The first batch of needles was launched on October 21, 1961.
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The needles were in a cylinder, embedded in naphthalene, otherwise known as mothballs.
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But they didn't choose that compound because they wanted the needles to smell like your
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grandmother's closet; naphthalene was convenient because it would evaporate in the near-vacuum of space.
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The idea was that when the cylinder was released, it would spin, creating a force on the needles
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that would push them out into space.
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That force, combined with the evaporation of the naphthalene, would disperse the needles.
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And… it didn't work.
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The test failed because even though the needles were pushed out of the cylinder, there were
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so many crammed into such a tight space that they clumped together into about a half dozen big clusters.
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But in May of 1963, the military tried again, putting 350 million more needles into 5 smaller
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cylinders instead of one big one.
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And that launch was successful.
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The needles transmitted radio signals much more reliably than our natural ionosphere,
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and it would've been pretty tough for the Soviet Union to go up there and destroy the ring.
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So if the test was successful, and the idea worked, why aren't we constantly bragging
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about our awesome metal space ring?
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Well, the main reason is that satellites became a thing pretty soon after that.
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And they were a way better solution than Project West Ford.
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Satellites are easier to put into orbit, can transmit and relay a much wider range of microwave
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and radio wave signals, and can be actively controlled and pointed at different things.
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Plus, it's a lot easier to fit a camera on a satellite than on a tiny copper needle.
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The other reason we don't use a giant ring of needles anymore is that there was a lot
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of protest from other scientists.
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Interference from the needles would've messed with sensitive telescopes, and there were
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a lot of people accusing the U.S. of “dirtying space”.
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So the military shelved Project West Ford, and Earth doesn't have a ring of tiny needles.
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But some leftovers from the project are still out there.
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The needles they launched were meant to fall to Earth within a few years, but dozens of
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batches of them are still being tracked by NASA, including plenty of clumps from that
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first failed test.
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Which is a lot of debris from just a couple of early tests.
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If nothing else, Project West Ford helped to shape how we treat the space around our
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planet, and made us much more aware of the debris we put up there.
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Today, the project stands as a both ridiculous and wonderful testament to our capacity to
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think beyond the obvious.
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And as the time humanity tried to turn Earth into a mini-Saturn.
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Thanks for watching this episode of SciShow Space, brought to you by our patrons on Patreon.
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