low frequency radio waves

How Humans Change Space Itself

It’s no surprise that humans influence the surface of our planet, but our reach can go farther than that. Humans affect space, too.

We know storms from the sun can naturally change the space environment around Earth, which can have an impact on satellites and power grids.

Scientists now know that Cold War era nuclear tests in the 1950s caused similar effects.

Particles around Earth are organized into layers known as radiation belts. These 1950s tests created a temporary extra layer of radiation closer to Earth. 

The effects of this could be seen all around the world. Aurora appeared at the equator instead of the poles, utility grids in Hawaii were strained, and in some cases, satellites above test sites were affected. 

Some types of communications signals can also affect Earth’s radiation belts

Very low-frequency waves, or VLFs, are used for radio communications. They are often used to communicate with submarines, because these waves can penetrate deep into the ocean. 

The waves can also travel far into the space environment around Earth. When these waves are in space, they affect how high-energy particles move, creating a barrier against natural radiation.

The outer edge of this radio-wave barrier corresponds almost exactly the inner edge of Earth’s natural radiation belts – meaning it could be human activity that at least partly shapes this natural radiation around Earth.  

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Humans Accidentally Created a Protective Bubble Around Earth
The interaction between radio transmissions and high-energy particles in space sometimes forms a shield around the planet, protecting it from dangerous cosmic phenomena.
By Marina Koren

A pair of NASA space probes have detected an artificial bubble around Earth that forms when radio communications from the ground interact with high-energy radiation particles in space, the agency announced this week. The bubble forms a protective barrier around Earth, shielding the planet from potentially dangerous space weather, like solar flares and other ejections from the sun.

Earth already has its own protective bubble, a magnetosphere stretched by powerful solar winds. The artificial bubble that NASA found is an accident, an unintended result of the interplay between human technology and nature. When humans want to communicate with submarines near the surface of the ocean, they use a type of radio communication known as very low frequency waves, or VLF, transmitted from stations on the ground. Some of the waves can stretch all the way out into Earth’s atmosphere and beyond, where they affect the movement of the radiation particles bouncing around in the region. Sometimes, the interaction between VLF and these particles creates a barrier that can be seen by spacecraft orbiting the planet.

This scale that compares the length of different electromagnetic radiation waves to marine creatures and objects might be helpful to people studying or teaching basic physics. 

A high-energy gamma ray’s wavelength is shorter than an atom’s width. A high-frequency, lower energy radio wavelength, meanwhile, can fit three blue whales lined up from snout to fluke. At the longest end of the spectrum sit extremely low frequency radio waves, which can have a wavelength more than 6,000 miles long and are naturally produced by lightning and stars. These can penetrate ocean water and have been used to communicate with submarines.

See a larger version of this graphic here. Courtesy of brookhavenlab, which uses high-energy X-rays to explore materials at the nanoscale.

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What’s Killing People in Day 5? (spoilers through Episode 5)

I don’t think it was the TV signal. Partially because that would leave the finale to be mostly denouement (and there needs to be something else), but mostly because the TV signal explanation doesn’t really line up with the observed effects.

Here’s what I have inferred so far:

1. People are dying once they reach slow-wave sleep, in which brain activity is predominated by delta waves, which are brain-wide oscillations that range in frequency from .1 to 4 Hz. This is the stage of sleep you reach shortly after you doze off, and you generally pass through a cycle of going into and then back out of this stage before you begin dreaming (REM).

This conclusion is supported by the fact that people beginning to doze off don’t die (they can be awakened just fine), people experiencing microsleeps or waking dreams don’t die (see Jake in just about every episode), and people who are thrown directly into REM (dreaming) sleep don’t die. It’s also supported by the fact that birds and mammals have died (both experience slow-wave sleep) but sharks (which do not experience slow-wave sleep) have not.

It may also be supported by the fact that Lex mentioned brains needing to reach a certain “frequency” in order to be killed by the phenomenon, because that suggests that a certain pattern of brain oscillations is what’s being interfered with.

2. There is a safe (or relatively safe) zone near the antipodes of the general area of Texas. The man at the broadcast station in Dallas mentioned that there were rumors of “safe sleep zones” in places like Malaysia and Australia. These landmasses are about as close as one can get to being on the opposite side of the world from Texas (the actual antipodes of which lie in the Indian Ocean). It appears that whatever is being transmitted from Texas and killing people is weakened enough by going all the way around or through the Earth that it has a lower chance of killing people in these areas.

3. People don’t appear to have been saved by bad TV reception. I’d expect that in some apocalyptic scenario, there’d be at least a fraction of government personnel and homespun crackpots who’d have fallout-hardened bunkers to hide in. And yet, we haven’t heard from any people who napped safely behind six feet of concrete. We also haven’t seen any locals who were protected from a majority of the signal by terrain features that block TV reception, like the various mountain ranges and “uplifts” dotted across Texas.

So, what I expect here is that it’s not the TV signal that was killing people. If it were, then people would be surviving in places with bad TV reception (even if it’s being bounced to every TV tower in the world, there are always spots) and not just at the antipodes of Texas. Furthermore, I think it’s unlikely that a signal in the MHz frequency range (as TV signals are) would interfere with a brain phenomenon on the order of single-digit Hz.

I do think it’s suspicious that the warning broadcast began around the time the phenomenon did, but I think that could be explained by the fact that someone out there, whom we haven’t met yet, knew this phenomenon was about to occur and called Jen Brown’s character to wake her up. That alone makes me suspect that whatever happened here was the result of a secret project, potentially one with unintended side effects—like killing people.

This also means that Ellis’s group is under the mistaken impression that it’s safe to go to sleep, which is bad. I’ll get back to that later, though.

I hear a hypothetical person asking, “But what do you think has been killing people then, if not the TV broadcast?”

I’m glad you asked, hypothetical person. My idea is below the cut for length.

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