Zoozve, Weirdo in the Solar System

We think we know our solar system. Obviously not every single object and rock, but at least the categories of objects in it. Sun, planets, moons, comets, asteroids, asteroid belt, meteorites, we’ve covered everything, right?

 

Not entirely, as Latif Nasser found out. His discovery started off from a kiddish solar system poster on his 2 yo son’s wall. As per that poster:

“Venus had a moon called Zoozve.”

What, he thought? Among the rocky planets (Mercury, Venus, Earth, Mars), wasn’t Earth the only one with a moon?

 

The NASA site said Venus had no moons. He googled up Zoozve. No results, at least not in English. That could have been the end of it – an error in a kid’s poster. But Nasser didn’t stop. He called up the illustrator of the poster – the man said he didn’t cook it up, that he found Zoozve on some online list of moons.

 

And then Nasser’s friend at NASA called him back. It wasn’t Zoozve, it was 2002-VE, an actual object near Venus. That fit – the “2” may have been changed into a “Z” at the time of printing the poster.

“But the weirder and harder question: is Zoozve (gonna just keep calling it Zoozve) a moon of Venus or not?”

 

Nasser tracked down the person who discovered Zoozve. The man couldn’t remember it all. He’d worked on the LONOS project which the US government had funded in the 90’s to identify asteroids. Once they knew it wasn’t a threat to hitting Earth, NASA stopped caring about it.

 

But two other astronomers continued to look into it. Was it a moon or not? The answer they came up with – Yes and No. It goes back to definitions!

“Turns out basically everything in our solar system orbits ONE thing. Earth orbits the Sun. The Moon orbits the Earth. Etc. If you are a body in the solar system, you hula hoop one bigger thing. That’s what you do … Except for Zoozve.”

 

Zoozve orbits the sun. But Venus has enough of a gravitational pull on Zoozve that it “also orbits Venus at the same time”.

“It’s a whole new category of thing. Something that orbits a star and a planet at once. Something that is not a moon, but also not not a moon. They call it … a quasi-moon.”

Even Earth has 7 quasi-moons, the latest one was discovered in 2023!

 

We’ve found many quasi-moons across the solar system. And they have different paths wrt their planets – some stay at a fixed spot wrt the planet (Trojans); others go in one direction around a planet but then flip and go the other way (horseshoes); and the rest wiggle back and forth (tadpoles).

 

Quasi-moons can even switch planets. Earth probably “flung” Zoozve to Venus about 7,000 years back. Zoozve will leave Venus in a few millennia, but where it will go is anybody’s guess.

“Anyway, I think this is so cool because everything else on the solar system map is so regular and orderly, but not quasi-moons! It's like we discovered a bunch of new weirdos who seem to be dancing to the beat of their own drum.”

And:

“We are just discovering this new class of paradoxical and promiscuous rock stars like Zoozve that remind us how weird and temporary and connected everything in the universe is. And how much we still don’t know.”