Origin of strange cosmic flashes identified after 10 years of mystery

LONDON, Jan. 4 (UPI) -- Scientists believe they have solved part of a cosmic mystery that's baffled them for a decade without any real answers -- only speculation -- until now.

Researchers in London have concluded that the source of some strange and very quick flashes of light, first detected in 2007 and were for years too elusive to accurately track, originate from a place they didn't expect -- a small galaxy beyond the borders of the Milky Way.

The conclusions are outlined in studies chronicled by the journal Nature and a paper by the Institute of Physics.

The results of the research are quite surprising to scientists, because most believed such powerful flashes, called Fast Radio Bursts (FRBs), must have been coming from a very bright galaxy, an exploding supernova or a supermassive black hole.

Not so.

"We now know that this particular burst comes from a dwarf galaxy more than three billion light-years from Earth," study author Shami Chatterjee told the BBC. "That simple fact is a huge advance in our understanding of these events."

A composite image of the field around FRB 121102 and its dwarf host galaxy, by the Gemini Multi-Object Spectrograph (GMOS) on the Gemini North telescope on Maunakea in Hawai'i. Scientists say the mysterious cosmic flash was detected in 2012 and ultimately traced to the dwarf galaxy. Image courtesy Gemini Observatory/AURA/NSF/NRC

For years, sky-watchers couldn't pinpoint the source of the bursts -- even with the help of long-range telescopes -- because they were too quick to map. Scientists would need to focus on an exact location in space at the very moment a flash occurred to get an idea.

In 2012, researchers recorded the 18th FRB at an observatory in New Mexico. Unlike the others, though, this flash repeated -- allowing the scientists to know where to look for the veritable needle in the haystack.

The recurrence of that particular burst, labeled FRB 121102, nine times over six months last year led scientists to the dwarf galaxy.

Much is still unknown about the FRBs, but astronomers are now at least confident they have an idea where they come from. The reports say tracing other FRBs will be difficult, and some scientists say a full understanding may never be known.

The research team has presented the findings at the 229th American Astronomical Society meeting in Texas, which concludes Saturday.