Unexplained radio signals are ‘from space, not Earth’

LONDON: Scientists have confirmed that the most mysterious signal in the universe is coming from space. Fast Radio Bursts — the strange signals that are occasionally sent down to Earth — have been pinned down to everything from aliens to a measuring mistake. But researchers have now ruled out the most down-to-earth explanation, that the signals aren’t actually coming from space but from interference on Earth.

New work confirms that the mysterious bursts of radio waves, tracked over 10 years, are actually coming from somewhere else in the universe. Fast Radio Burst (FRBs) were first noticed 10 years ago. They last for only a fraction of a second but seem to be coming from vast distances away and are a billion times brighter than anything seen in the Milky Way.

The bizarre signals — and the fact that they appear to line up in a peculiar arrangement and come from one specific place — have led some to suggest they might even be messages from aliens. But others explained them by suggesting they could be local interference, tricking astronomers into thinking they had found the unusual messages. In 2015, for instance, it emerged researchers had actually detected their own microwave in one experiment, rather than the mysterious message from aliens they thought they found.

But the new work proves that the messages do in fact originate outside the Earth’s atmosphere. The scientists came to the conclusion after detecting three of the FRBs using the Molonglo radio telescope that sits outside Canberra, in Australia.

That telescope has a huge focal length that allows it to look at large parts of the sky. That makes it excellent for catching Fast Radio Bursts, which come only intermittently.

Manisha Caleb, a PhD candidate at Australian National University, Swinburne University of Technology and the ARC Centre of Excellence for All-sky Astrophysics, confirmed the messages were extraterrestrial by re-engineering that telescope and sifting through the 1000 TB of data it provides each day — finding three new Fast Radio Bursts, all of which definitely came from space.

Scientists will now work to further understand where those messages are coming from. One of the bursts has already been pinned down to a specific galaxy but far more remain mysterious.

The Molonglo telescope is expected to find the source of more bursts in the future.