Astronomers have been making something of a habit of discovering exoplanets as of late. Spotting the telltale signs of a planet orbiting a far-away star is still pretty difficult, but powerful telescopes are making it a bit easier, and new planets are being found and documented with impressive regularity. NGTS-1b is one such planet, and scientists just revealed its discovery today, but there’s just one problem: it shouldn’t even exist.

“In theory, it is impossible,” researchers from the DLR Institute of Planetary Research say of the discovery that the tiny dwarf star NGTS-1 is hosting a massive gas giant that rivals Jupiter for size. It’s an incredible find that could dramatically alter the current understanding of how planets form.

The planet and its tiny star are the very first discoveries by the brand new Next-Generation Transit Survey (NGTS) installed in Chile, and it sure is a doozy. The system uses a total of 12 telescopes to gaze into space and spot the faint dips in star brightness that serve as hints of orbiting planets.

The gas giant orbits a star that is only about half the size of our own sun, and that’s where scientists fail at explaining their relationship. Up until now, dwarf stars like NGTS-1 were thought to be able to host smaller rocky worlds, but nothing remotely as large as NGTS-1b appears to be. It had always been assumed that such tiny stars wouldn’t have had the excess material orbiting them to form such massive worlds.

“The discovery of NGTS-1b was a complete surprise to us — such massive planets were not thought to exist around such small stars,” Daniel Bayliss, lead author of the research, explains. “The planet is about 25 percent the radius its host star. This makes is very large compared to its host star! For comparison, Jupiter is only about 10 percent the radius of our sun.”

NGTS-1b is orbiting its star at a very close distance, and its orbit causes it to experience a full “year” in the equivalent of fewer than three Earth days.

Going forward, the researchers hope to be able to support their findings by discovering other gas giants orbiting dwarf stars, at which point they’ll be forced to come up with an explanation as to how they can even exist in the first place.