Some of science’s biggest mysteries are in outer space. The identity of dark matter and dark energy involve fundamental questions about how the Universe is constructed. If you instead are interested in mysteries about what the Universe is doing, then fast radio burst may be at the top of the enigma list.

They are, as their name suggests, fast, lasting for only a handful if milliseconds. And they also involve huge quantities of energy at radio wavelengths, just as promised. But beyond that, we know almost nothing about them, and we have only observed about 35 of them as of last count. Their rarity and transient nature have helped keep them from being better understood.

But this week’s edition of Nature includes a collection of 20 new observations, all occurring since the start of 2017. Unfortunately, the new burst don’t tell us much about how they’re generated. And, to make matters worse, they suggest that our best bet for figuring it out—the only repeating burst source we know about—is probably unlike all the other sources we’re seeing.