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An Asteroid With a ‘Gremlin’ Moon Flew By Earth on Halloween

Trend alert: Halloween asteroids are a thing.
Concept art of asteroids approaching an Earthlike world. Image: NASA/JPL-Caltech

It looks like Earth has been visited by trick-or-treating Halloween asteroids for the second year in a row. New NASA footage reveals that asteroid 2003 YT1, estimated to be 2.63 kilometers (1.6 miles) across, zipped past Earth on Monday at a distance of about 5.3 million kilometers (3.3 million miles). Orbiting the tiny asteroid was an even tinier moon, barely visible in the radar data shown here. NASA dubbed the satellite a "gremlin" in keeping with the season.


Footage of Halloween asteroid 2003 YT1. Image: NASA Jet Propulsion Laboratory/YouTube

On top of that, an asteroid called named 2016 UR36, discovered just last week, also came knocking on Earth's door on Monday. This one made a much closer pass, flying by at only 1.3 times the distance between Earth and the Moon (310,000 miles). It's absolutely tiny, no more than 25 meters across, and it didn't wear a spooky costume or anything. But it has been deemed a Halloween asteroid by some regardless, by virtue of its timing.

READ MORE: Vampire Stars and Franken-Galaxies: The Spookiest Things in Outer Space

These encounters are particularly weird considering the universe served up a skull-shaped dead comet called 2015 TB145 on Halloween last year, which also passed at about 1.3 times the distance between Earth and the Moon.

Animated GIF with resolution of 25 feet (7.5 meters) per pixel. Image: NAIC-Arecibo/NSF

We at Motherboard even speculated about the possibility that this year we might get another Halloween asteroid in a piece published Monday. "Just in case you forgot, a skull-shaped dead comet zipped by Earth last year on Halloween night," I wrote in that article. "Perhaps we'll receive a similar trick-or-treater at our planetary door this year. My money's on a pumpkin-shaped asteroid that sounds like a theremin."

Okay, looks like I was wrong this time around, but who could have predicted space gremlins? The question now is: What will Halloween 2017 deliver up? I'm all in again on a pumpkin-shaped asteroid that sounds like a theremin.

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