NASA has confirmed the discovery of a fast-moving interstellar object called 3I/ATLAS, traveling at about 36 miles per second. Though it’s large—about seven miles wide—it poses no threat to Earth, according to NASA. The closest it will come is 170 million miles away.

The object was first detected on July 1 by the ATLAS asteroid warning system. It’s the third interstellar object ever observed in our solar system, which explains its name: “3I” for third interstellar, and “ATLAS” for the system that found it.

Despite NASA’s reassurances, some scientists—including Avi Loeb—suggest 3I/ATLAS could be an alien spacecraft trying to avoid Earth’s telescopes. They said it may even require “defensive measures” if proven hostile. However, they also admitted it most likely behaves like a natural comet.

NASA scientist Paul Chodas dismissed alien theories. “It’s not artificial,” he said. “It’s a natural object, likely traveling through space for hundreds of millions of years.” So, while it may be a fascinating visitor, it’s not here to attack.