There’s too much gold in the universe. No one knows where it came from.

Something is raining gold across the universe. But no one knows what it is.

Here’s the problem: Gold is an element, which means you can’t make it through ordinary chemical reactions — though alchemists tried for centuries. To make the sparkly metal, you have to bind 79 protons and 118 neutrons together to form a single atomic nucleus. That’s an intense nuclear fusion reaction. But such intense fusion doesn’t happen frequently enough, at least not nearby, to make the giant trove of gold we find on  Earth and elsewhere in the solar system. And a new study has found the most commonly-theorized origin of gold — collisions between neutron stars — can’t explain gold’s abundance either. So where’s the gold coming from? There are some other possibilities, including supernovas so intense they turn a star inside out. Unfortunately, even such strange phenomena can’t explain how blinged out the local universe is, the new study finds

what about those odder, star-flipping supernovas? This type of star explosion, a so-called magneto-rotational supernova, is “a very rare supernova, spinning very fast,” Kobayashi told Live Science.

During a magneto-rotational supernova, a dying star spins so fast and is wracked by such strong magnetic fields that it turns itself inside out as it explodes. As it dies, the star shoots white-hot jets of matter into space. And because the star has been turned inside out, its jets are chock full of gold nuclei. Stars that fuse gold at all are rare. Stars that fuse gold then spew it into space like this are even rarer.

But even neutron stars plus magneto-rotational supernovas together can’t explain Earth’s bonanza of gold, Kobayashi and her colleagues found.

“There’s two stages to this question,” she said. “Number one is: neutron star mergers are not enough. Number two: Even with the second source, we still can’t explain the observed amount of gold.”