New York City residents recently felt they were living in a sci-fi adventure.

On Nov. 2, one resident spotted a green liquid spilling from sewer grates near the World Trade Center. Dan Pantelo shared his findings onX(formerly known as Twitter) with a photo of the bright green liquid surrounding the sewer grate and pouring into the city streets.

Daniel Pantelo /Storyful

The green “slime”

“So there’s literal green sludge bubbling up from the ground next to World Trade Center right now,” Pantelo wrote.

Pantelo asked other X users if anyone knew what was the cause of the green liquid, and wrote in afollow-up post, “Can anybody explain this or are we just living in full blown Gotham rn.”

According to theNational Park Service, dye tracing is a standard practice used to track water’s movement. The technique “helps scientists visualize how water moves from one place to another,” the National Park Service notes.

The green “slime”.Daniel Pantelo /Storyful

NYC street green ooz

After Pantelo shared the original photo, he returned to the scene the following day and provided an update. “UPDATE: it’s still there, people are walking through it casually, sometimes a small crowd gathers around and stares at it,” wrote Pantelo.

Despite the disclaimer, Pantelo joked that he wasn’t convinced the liquid was just dyed liquid. “Contrary to the community note, I think the sludge is radioactive ooze. Source? Divine intuition,” hewrote.

Oneuseredited the original photo to include theTeenage Mutant Ninja Turtleslogo and one of the Ninja Turtles popping out of the sewer grate, and simply captioned the post, “Love this comic.”

Meanwhile, anotheruserwrote, “Ghostbuster slime was pink. This is Ninja Turtle Ooze.”

Others noted the liquid’s similarities to anepisode ofSpongebob Square Pantsand the movieAlien.

“Are Alien and Predator fighting in the subway again?” wrote oneuser.

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source: people.com