Here in the Milky Way galaxy, all of our planets rest on the same flat plane, circling around the equator of the sun; for argument's sake, let's say we're all on about the same horizontal alignment. This matches up with our outstanding of gravity and poles, and it's something that scientists have seen repeated in other galaxies, too.
Until now, at least. The New York Times reports:
What's unusual is the inclinations of the outer two planets, HD 3167 c and d. Whereas in our solar system all the planets orbit in the same flat plane around the sun, these two are in polar orbits. That is, they go above and below their star's poles, rather than around the equator as Earth and the other planets in our system do.
Now scientists have discovered the system is even weirder than they thought. Researchers measured the orbit of the innermost planet, HD 3167 b, for the first time — and it doesn't match the other two. It instead orbits in the star's flat plane, like planets in our solar system, and perpendicular to HD 3167 c and d. This star system is the first one known to act like this.
If you're having trouble wrapping your head around this, Vincent Bourrier of the University of Geneva in Switzerland, who lead the new study on this system that was published last month, explained the view if you were standing on one of these planets: "If you had a telescope and you were looking at the trajectory of the other planets in the system, they would be going vertically in the sky."
In other words, it's a vertical stack of planets, rather than a horizontal one (relatively speaking).
There are different theories as to why this galaxy seems tilted at a right-angle; there may be a Jupiter-sized planet nearby affecting the gravity, for example. For now, they're still figuring that out. In the meantime: it's just another weird cool space thing!
Star System With Right-Angled Planets Surprises Astronomers [Jonathan O'Callaghan / The New York Times]
Full Disclosure: I also write for Wirecutter, which is owned by the New York Times company, which publishes the New York Times