Citizen science project to find galactic bursts using selfie-taking pocket radio receivers
Artist’s impression of a fast radio burst (Photo credit: Jingchuan Yu, Beijing Planetarium / NRAO)
Friends, take out your mobiles in the name of science! Astronomers from the Harvard-Smithsonian Center for Astrophysics are trying to look for fast radio bursts in the Milky Way galaxy with “low-cost radio receivers.” And by that, they mean, your smartphones.
Galactic fast radio bursts (FRBs) have left astronomers scratching their heads. The high-energy radio flashes last about a millisecond and have only been spotted in distant galaxies, making them difficult to study with radio telescopes.
Researchers hoping to understand the origin of these radio flares are looking closer to home. Professors Dan Maoz and Avi Loeb, from Tel Aviv University and Harvard University, believe an active FRB might be right under our noses.
“If fast radio bursts originate from galaxies at cosmological distances, then their all-sky rate implies that the Milky Way may host an FRB on average once every 30 to 1,500 years. If many FRBs persistently repeat for decades or for centuries, a local giant FRB could even be active now,” Maoz and Loeb wrote in a paper accepted for the Monthly Notices of the Royal Astronomical Society.
Its signal would be approximately 1GHz and would have a flux density of 3 × 1010 Jansky – large enough to be detected by mobile phones, Wi‑Fi or GPS. The idea is to create a “Citizens-Science” app that would continuously listen for and record radio signals. Sound files would be periodically uploaded to a website, where all the data can be correlated to identify the position of possible FRBs.
“An FRB in the Milky Way, essentially in our own back yard, would wash over the entire planet at once. If thousands of cell phones picked up a radio blip at nearly the same time, that would be a good sign that we’ve found a real event,” said Dan Maoz, lead author of the study.
“[Since] the size of the Milky Way is a million times smaller than the size of the Universe, a local [FRB] event would be a trillion times brighter than the most distant events. Because an FRB from the Milky Way should be so much brighter, it can be detected with a cell phone or a small electronic device that costs tens of dollars instead of a giant radio dish,” Loeb told The Register.
Another option is to employ a network of software defined radio (SDR) kits – popular among radio tinkerers – that can be purchased for as little as $10. The devices can be plugged into the USB port of a laptop or desktop, and data can be uploaded to a website.
But it may not be as straightforward as that, the researchers admitted. Cell phones and SDRs will also detect random noises that could potentially swamp the FRB signals. Little is known about these galactic flares, and if they aren’t repeated then nobody can say how common the events might be.
“A reasonable expectation is then that FRB numbers increase at decreasing luminosities. If so, lower-luminosity FRBs should be detected more frequently by the global cellular network,” the paper said.
“FRBs are extremely bright and their nature is not understood. They require coherent emission by many electrons, of the type that you get in a radio antenna or a laser,” Loeb explained.
He also said their origin was “so puzzling” that it led him to write a paper that examined if the blazes could be linked to “advanced civilizations” living far away in the cosmos. ®