ASTRONOMERS are confused about an unusual radio signal from a distant star 16,000 light-years away.
The mysterious intermittent radio signal was found purely by chance.
The odd signal from across the galaxy "isn’t like anything astronomers have seen before," according to two space experts based in Australia.
The team chanced upon the signal while researching space using the Commonwealth Scientific and Industrial Research Organisation's (CSIRO) radio telescope in Australia's outback.
"It can survey large volumes of the universe very quickly. This makes it very well suited for detecting new and exotic phenomena," said Manisha Caleb, a lecturer at the University of Sydney, and Emil Lenc
research scientist, Space and Astronomy, CSIRO.
Cruise passengers stranded on New Year 'trip from hell' after fungus outbreak
BURSTS OF RADIO WAVES
"We sometimes detect sporadic bursts of radio waves originating from across the vast expanse of the universe," they wrote on research based website The Conversation.
"We call them radio transients: some erupt only once, never to be seen again, and others flicker on and off in predictable patterns.
"We think most radio transients come from rotating neutron stars known as pulsars, which emit regular flashes of radio waves, like cosmic lighthouses."
Neutron stars are the remnants of the cores of huge stars that have reached the end of their lives.
"Recently, we discovered a radio transient that isn’t like anything astronomers have seen before," the experts added.
STRANGE FLASHES
"Not only does it have a cycle almost an hour-long - the longest ever seen - but over several observations we saw it sometimes emitting long, bright flashes, sometimes fast, weak pulses – and sometimes nothing at all.
"We can’t quite explain what’s going on here. It’s most likely a very unusual neutron star, but we can’t rule out other possibilities."
The suspected neutron star has been named ASKAP J1935+2148.
The mystery object is located in the plane of the Milky Way, some 15,820 light-years from Earth, according to Science Alert.
"The signals themselves are like none ever seen before - the star goes through periods of strong pulses, periods of weak pulses, and periods of no pulses at all," the website added.
We grew up devout Christians with no sex…now we're swingers in open marriage
Further observations were undertaken at a more sensitive radio telescope in South Africa.
But the astronomers remain baffled.
Radio waves from ASKAP J1935+2148 were coming out like a "corkscrew" as the signal traveled through space.
"The origin of a signal with such a long period remains a profound mystery, with a slow-spinning neutron star the prime suspect," said Caleb and Lenc.
OLD STAR
"We cannot rule out the possibility the object is a white dwarf – the Earth-sized cinder of a burnt-out star that has exhausted its fuel.
"White dwarfs often have slow rotation periods, but we don’t know of any way one could produce the radio signals we are seeing here.
"What’s more, there are no other highly magnetic white dwarfs nearby, which makes the neutron star explanation more plausible.
"One explanation might be that the object is part of a binary system [where two stars orbit around a common centre of mass] in which a neutron star or white dwarf orbits another unseen star."
They stressed that further research was needed to establish what the mystery object is.
It’s likely there are many other objects like it elsewhere in our galaxy, waiting to be discovered.
Researchers, Australia
The intriguing findings should prompt a further look at decades-old research into neutron stars or white dwarfs, and how they emit radio waves, the experts suggested.
"We don’t know how long ASKAP J1935+2148 has been emitting radio signals," the pair added.
"We were quite fortunate we happened to catch sight of ASKAP J1935+2148. It’s quite likely there are many other objects like it elsewhere in our galaxy, waiting to be discovered."
The team's research is published in Nature Astronomy.
LUNAR LANDER
It comes amid an update about the lunar lander named Odysseus which touched down near the moon’s South Pole in February.
Astrophysicist Jack Burns, of a public research university in Boulder, Colorado, hailed it as the “dawn of radio astronomy from the moon.”
Burns is co-investigator on the radio experiment that flew aboard Odysseus called Radio wave Observations at the Lunar Surface of the photo Electron Sheath (ROLSES).
Antennas will take data and send that back to Earth, he told the University of Colorado today.
“We viewed Earth as an exoplanet, or a planet orbiting another star,” Burns said in an update.
“That enables us to ask: What would our radio emissions from Earth look like if they came from an extraterrestrial civilization on a nearby exoplanet?”
NASA has given the green light to a second ROLSES experiment, which will fly on another lander, most likely in 2026.
