A study published this Wednesday found the location from which one radio burst seen in 2012 came from. The source is a surprise for the scientists as it originates from a dwarf galaxy that is 2.5 billion light years away from Earth.
The Fast Radio Burst (FRB) is one of the most mysterious astronomical phenomena for the scientific community. In fact, this particular radio burst helped the investigation discover its origin because is the only FRB registered that has repeated itself.
Three different studies proved the origin of this radio burst dubbed FRB 121102. The results show how the galaxy that emitted the burst is located almost 3 billion light years from Earth and is very humble when comparing to most known galaxies. This one possesses a body of stars considerably smaller than larger galaxies like the Milky Way.
The great news regarding this discovery is that scientists are closer to understanding how this phenomenon occurs and why because now there is knowledge about the source of the burst.
According to Cees Bassa, an astronomer at the Netherlands Institute for Radio Astronomy (ASTRON) and a co-author of one of the three new studies, the fact that the source is a dwarf galaxy is unexpected and could explain the origin of the burst.
Postdoctoral researcher, Shriharsh Tendulkar, explained a bit what they were hoping to find and also the relation between this event and neutron stars.
“One would generally expect most FRBs to come from large galaxies which have the largest numbers of stars and neutron stars. This dwarf galaxy has fewer stars but is forming stars at a high rate, which may suggest that FRBs are linked to young neutron stars,” Tendulkar said in an official statement from the McGill University in Montreal released this Wednesday.
Neutron stars are stellar objects that measure about 1.4 times the size of the sun. These solid structures are formed from the explosion of large stars, and as the gravity pressures the body of the object, both protons and electrons combine to make neutrons, hence the name “neutron star.”
About the ‘Fast Radio Bursts’
John Mulchaey, acting director at Carnegie Observatories, describes this phenomenon as “one of the biggest mysteries of the universe.” According to NASA, there has been 18 FRB registered since its discovery in 2007, and only one of those bursts have been seen live, when in May 2014, astronomers using the Parkes Radio Telescope in Australia were able to identify the event.
These cosmic flashes only last about a fraction of a 1 second, but in that time, they can release the total amount of energy that our Sun will irradiate in the next 10,000 years. Although only 18 of these phenomena have been registered by astronomers worldwide, specialists say that these bursts happen in the sky every 10 seconds.
For scientists to detect one of these FRBs, one telescope must be observing the region in which the appearance takes place at the same exact moment of the event. Also, the astronomers can’t alert other telescopes for them to see the mentioned event. These complications make tough for scientists to analyze their observations and determine the distance and location of the source.
How did scientists manage to observe FRB 121102 twice?
Shami Chatterjee, Senior Research Associate at Cornell and one of the astronomers that helped with the discovery of the origin of the mysterious phenomenon, explained that the FRB 121102 was capable of repetition as a cataclysmic event didn’t produce it.
Even when the FRB 121102 didn’t present a particular pattern, the investigation team knew that the burst had great possibilities of reappearing at the same region. This allowed the researchers to observe if the burst appeared again, but with several and more capacitated telescopes.
After the discovery of the burst back in 2012, by the Arecibo Observatory in Puerto Rico, scientists took the task of performing hours and hours of observation. Chatterjee and his research team used the Very Large Array Observatory in New Mexico for a six-month period. In that time, they added up 83 hours of observations.
They were able to watch the radio wave burst up to nine times, before defining the particular location of the source. This definition was made after the analysis made by the astronomers from Hawaii’s research center where there is the 8-feet Gemini North Telescope. After all the investigations, the studies showed that the source galaxy was both a dwarf one and also one that is very far from Earth.
“Before we knew the distance to any FRBs, several proposed explanations for their origins said they could be coming from within or near our own Milky Way galaxy. We now have ruled out those explanations, at least for this FRB,” Tendulkar said in an official statement regarding the FRB source.
According to Sarah Burke-Spolaor, an astronomer at West Virginia University, this phenomenon could help to explain Einstein’s theory of relativity, as it shows how an FRB can cross enormous distances in such large cosmological time spans.