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Here's Why New York City's Blue-Sky Electrical Explosion Was So Big

Thursday night, an explosion at a Con Edison electrical facility lit up the entire New York City Sky an unsettling shade of aqua.
The New York City sky in a shade of aqua.

At around 10PM last night, an explosion at a Con Edison facility in Astoria, Queens in New York sent an aqua-blue pulsating light across the entire New York sky for a few hours.

LaGuardia Airport promptly lost power, and an unknown number of Queens residents also lost power, according to a tweet from Con Edison.

Con Ed, the New York Police Department, and the New York Fire Department did not immediately respond to Motherboard’s request for comment. But the NYPD confirmed in a tweet that the light was caused by an incident involving Con Edison, and a tweet from NYPD Chief Terence Monahan claimed that there were no injuries, and the fire was under control as of 11:13 PM on Thursday. It’s not yet known how much monetary damage was caused by the explosion.

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According to tweets from Con Edison, the light was caused by an electrical fire involving transformers at the company's Astoria substation at around 20th Ave. and 31st St. For the most part, people rejoiced at the prospect that—yes, thank god—the aliens are here, the apocalypse has come, we are all finally going to die. Others attributed the event to Jeff Bezos: either he was arriving, or he was being warned to stay far away from the city.

Motherboard is sorry to confirm that the beautiful light can be attributed to neither of those two things. Here’s what’s actually going on:

Transformer explosions often result from an insulation failure (in the case of a transformer, the insulator keeps the transformer cool.) Depending on what type of insulator is used, mechanical stress on the transformer, environmental effects like temperature, ice, and pollution could all cause damage over time, or age could damage it.

Transformers are basically traffic directors of energy flowing through an electricity generation system, like the one in Astoria. So damage that makes the transformer unable to regulate its temperature makes those transformers more vulnerable to exploding or catching fire.

Picture a hot chamber full of electric circuits, getting sparked with electricity from the massive energy plant surrounding it. Now consider this: when the chamber gets hot enough, the insulating oil (often made from petroleum) becomes electrically conductive. This is a recipe for disaster.

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The heat, electricity, circuits, and insulating oil is a perfect cocktail for an uncontrolled flame. Transformers are designed to shut themselves off before they catch fire, but that doesn’t always work. According to Cassie Rodenberg of Popular Mechanics, that amount of time could be as little as 60 milliseconds—the transformer catches fire.

Once the fire starts, it quickly gets out of control. The oil in the transformer burns up into a gas, which puts pressure on the transformer before it completely explodes. Because of how quickly pressure builds up inside the transformer, this explosion can occur as a fireball.

When this fireball enters a high-temperature, high-energy plasma state, electrons are literally ripped from the atoms that make up the gases in the area. When these electrons recombine with other gases, we see visual light (or, colors.)

But the color we see doesn’t solely depend on which gas it combines with; it also depends on factors like the pressure on and density of these electrons (both of these factors are influenced by heat.) For instance, oxygen-fueled flames can appear blue simply if the temperature is hot enough.

There’s also a number of gases that could emit blue-green light in a plasma state. For instance, carbon dioxide burns blue, copper burns green, various compounds burn blue-green.

So altogether, with all of the factors that could have affected the color of the sky, we don’t have a definitive answer as to why the sky was that jarring shade of turquoise.

Here’s the strange thing: this is not the first time that a transformer explosion has lit up the sky blue. Over the past several years, YouTube users from Vancouver, Canada and Fort Worth, Texas allege to have captured the event in their respective hometowns

So what can we take away from this? If the public reaction to explosion is any indication, we’re fucked if something very serious and also life threatening happens in a major metropolitan center.