Australasian Science Magazine

By David Reneke

Fast radio bursts have been detected near Canberra, and now you can join the hunt for a ninth planet in our solar system.

The search for extraterrestrial intelligence has looked for many different signs of alien life, from radio broadcasts to laser flashes, without success. However, new speculative research suggests that the mysterious phenomena called “fast radio bursts” could be evidence of advanced alien technology. A big call? You bet!

Specifically, they say these FRBs might be leakage from planet-sized transmitters powering interstellar probes in distant galaxies. Pretty much like a solar sail I guess. Either way, FRBs present one of modern astronomy’s greatest mysteries.

Manisha Caleb, a PhD candidate at the Australian National University, Swinburne University of Technology and the ARC Centre of Excellence for All-sky Astrophysics (CAASTRO) has now confirmed that these signals really do exist, having worked with Swinburne and University of Sydney colleagues to detect three FRBs with the Molonglo radio telescope 40 km from Canberra.

Discovered almost 10 years ago at CSIRO’s Parkes radio telescope, FRBs are millisecond-duration intense pulses of radio light that appear to be coming from vast distances. They are about a billion times more luminous than anything we have ever seen in our own Milky Way galaxy.

So, what or who in the universe is transmitting short bursts of radio energy across the cosmos, seemingly in our direction? One potential answer to the mystery is that they weren’t really coming from outer space, but were some form of local interference tricking astronomers into searching for new theories of their radio energy. “Conventional single dish radio telescopes have difficulty establishing that transmissions originate beyond the Earth’s atmosphere,” says Swinburne’s Dr Chris Flynn.

The Molonglo telescope has a huge collecting area of 18,000 m2 and a large field of view, which makes it excellent for hunting for FRBs. Caleb’s project was to develop software to sift through the 1000 TB of data produced each day. Her work paid off with the three new FRB discoveries.

Public Search for Ninth Planet
NASA is inviting the public to help search for possible undiscovered worlds in the outer reaches of our solar system and in neighbouring interstellar space. A new website called Backyard Worlds: Planet 9 (http://backyardworlds.org) lets everyone participate in the search by viewing images captured by NASA’s Wide-field Infrared Survey Explorer (WISE) mission.

WISE scanned the entire sky between 2010 and 2011, producing the most comprehensive survey at mid-infrared wavelengths currently available. In 2013 it was given a new mission assisting NASA’s efforts to identify potentially hazardous near-Earth objects, which are asteroids and comets on orbits that bring them into the vicinity of the Earth’s orbit.

The new website uses the data to search for unknown objects in and beyond our own solar system. In 2016, astronomers at Caltech in California believed an as-yet undetected “Planet Nine” could be so bright it would show up in WISE data. Planet Nine would likely be two to four times the Earth’s diameter, and ten times its mass, orbiting the Sun every 15,000 Earth years, or about 800 times the distance between Earth and the Sun.

The search also may discover more distant objects like brown dwarfs, sometimes called failed stars, in nearby interstellar space. By using Backyard Worlds: Planet 9, the public can help astronomers discover more of these strange rogue worlds by using their own computer. If you find it you may have naming rights!

Backyard Worlds: Planet 9 relies on human eyes because we easily recognise the important moving objects while ignoring the artefacts. It’s a 21st century version of the technique astronomer Clyde Tombaugh used to find Pluto in 1930.

On the website, people around the world can work their way through millions of “flipbooks” – brief animations showing how small patches of the sky changed over several years. Moving objects flagged by participants will be prioritised by the science team for follow-up observations by professional astronomers.

Backyard Worlds: Planet 9 has the potential to unlock once-in-a-century discoveries, and it’s exciting to think they could be spotted first by a citizen scientist. The tantalising thing is it may be found by a reader of this magazine – someone like you!