After scientists reported to have pinpointed the home galaxy of a fast radio burst (FRB) last week, other theories shed doubt on the accuracy of the findings, including one claiming that the detected afterglow was actually from another galaxy that happened to overlap with the galaxy reported in the initial findings.

Now, for the first time ever, a new study has discovered FRBs that keep repeating, and the team claims that this conflicts with both of the previous explanations and points to a source other than a massive star collision.

Until now, FRBs, bright radio flashes that last just a few milliseconds, have never been known to repeat themselves. Although scientists believe that they may occur thousands of time a day, to date they have detected less than 20 of them.

In the first study, the age of the galaxy named as the source of an FRB, along with the strength of the radio burst, suggested that the source was a collision between massive stars. However, the new findings reveal that FRBs can repeat themselves - something that massive collisions never do.

"I don't think the final nail is in the coffin on that," Jason Hessels, corresponding author of the latest study, said. "There are more observations that need to be done, but it seems less convincing than it did last week," although he entertained the idea that there is more than one type of FRB.

Edo Berger, a scientist from Harvard University who is working on a currently unpublished paper that also refutes the first study's theory on the FRB origin, believes that the signal analyzed in the paper lasted far too long to be an FRB, instead pointing to another intergalactic space phenomenon as the source.

"Essentially I would say that the whole rationale behind the paper has gone away within about two or three days of when it was published," he said.

So if FRBs don't originate from colliding stars, where do they come from? Hessels and his team plans to explore this question in future experiments using the powerful Arecibo telescope along with other telescopes in Europe in order to accurately identify the origins of the mysterious repeating FRBs.

The findings were published in the Mar. 2 issue of Nature.