NEW YORK (CBSNewYork) -- The New York City Council held a hearing Monday on what caused December's "Astoria Borealis."
A malfunction at a Con Edison substation in Queens sent out a blue light that could be seen for miles, CBS2's Jenna DeAngelis reported.
When the city skyline lit up that night, it was a moment that was hard to believe and impossible to forget.
And if you just so happened to be on social media at the time, you likely saw the supernova shades spark some interesting theories.
"I thought aliens were landing. It was all kinds of noise. You think nuclear war, maybe. You think North Korea or something. You really don't know what's going on," Astoria resident David Brown said.
"It looked apocalyptic. It was crazy," another man added.
WATCH: Chopper 2's Dan Rice Over the Scene in Queens
But there were no aliens. It was just an electrical flash after voltage-monitoring equipment failed at a Con Ed substation in Astoria. It was similar to how a circuit breaker works in your home. Con Ed said the systems that should have just stopped it immediately didn't, which is why the event lasted about four minutes.
Fortunately, there were no major injuries, but there were temporary power outages, among other community concerns.
"Families' homes shook. There was air quality concerns. There was safety concerns," council member Costa Constantinides said. "We're gonna get some hard answers from Con Ed as to what happened."
WATCH: Gov. Andrew Cuomo Discusses Con Ed Explosion
The council's Environmental Protection Committee, which Constantinides chairs, heard more from the utility at a meeting on Monday.
"We replaced the faulty equipment, installed a redundant system, and are working directly with the manufacturer to minimize the chance of this happening again," said Milovan Blair, Con Ed's senior VP for central operations.
Monday's meeting also focusing on how that blue night could result in a more green future here.
"We need to think about how with solar, wind, renewable energy, battery storage, that we replace these gas-powered power plants in New York City and take us to a greener renewable future," Constantinides said.
Constantinides also said he hopes pass legislation that would require the city to study making this transition. Con Ed said its on board with cleaner energies but wants to be clear about what happened in December.
"What happened in Astoria was in a substation, which you would need for a solar farm, wind farm, any kind of green power that you might set up. It still could have happened regardless of what type of power we use," spokesman Michael Clendenin said.
Monday was really about starting the conversation for a greener future. Constantinides is hoping it will result in passing legislation that says the city has until the end of 2019 to come up with a plan.
At the meeting, the parties involved also discussed how to better inform the community if an issue like this arises again in the future.
for more features.