Brisbane, Australia – Surprising radio waves from distant stars could reveal the presence of undiscovered planets in these solar systems, according to Australian researchers. A team from the University of Queensland used the world’s most powerful radio antenna to make the discovery, which opens the door to a new method of detecting new worlds in space.
“We have discovered signals from 19 distant red dwarf stars, four of which are best explained by the existence of planets orbiting them,” Dr Benjamin Pope said in a report. university outing.
“We have known for a long time that the planets in our own solar system emit powerful radio waves when their magnetic fields interact with the solar wind, but the radio signals from planets outside our solar system had not yet been picked up,” he adds. Dr Pope. “This discovery is an important step for radio astronomy and could potentially lead to the discovery of planets throughout the galaxy.”
Radio signals can bounce off hidden plants
In the past, astronomers could only detect nearby stars by radio broadcasts from space. Everything else from the sky was either interstellar gas or signals from alien phenomena like black holes.
Now, however, radio astronomers can see distant stars (like the Sun) and use their observations to determine if there are planets orbiting them. Dr Pope’s team focused on a cluster of red dwarf stars, which are generally smaller than our sun and have intense magnetic activity. This can lead to stellar flares and detectable radio emissions.
So what is it that makes these radio signals so important? Lead author of the study, Dr Joseph Callingham of the University of Leiden, says the team is confident that the signals they are detecting come from the interaction between red dwarfs and orbiting planets. These signals are similar to the interactions that astronomers see between Jupiter and its moon, Io.
âOur own Earth has auroras, commonly recognized here as the Northern and Southern Lights, which also emit powerful radio waves – this comes from the interaction of the planet’s magnetic field with the solar wind,â says Dr Callingham. “But in the case of Jupiter’s auroras, they are much stronger because its volcanic moon Io projects matter into space, filling Jupiter’s environment with particles that result in exceptionally powerful auroras.”
“Our model for this radio show of our stars is a magnified version of Jupiter and Io, with a planet enveloped in a star’s magnetic field, feeding matter into vast currents that also feed bright auroras,” the continued. searcher. âIt’s a show that has caught our attention light years away.
Scientists hope to discover more worlds in the next decade
While the signals don’t fully confirm the existence of planets in these solar systems, the researchers say this is the most likely conclusion. Additionally, Dr. Pope notes that these worlds appear to be smaller than ours.
“We cannot be 100% sure that the four stars that we think planets have are indeed host planets, but we can say that a planet-star interaction is the best explanation for what we are seeing,” explains Dr Pope. “Follow-up observations have ruled out planets more massive than Earth, but there is nothing to say that a smaller planet wouldn’t.”
Currently, the Low Frequency Network (LOFAR) in the Netherlands can only monitor stars up to 165 light years from Earth. However, by 2029, scientists hope the Square Kilometer Array radio telescope from Australia and South Africa will be online and able to see the stars even further away.
Pope and Callingham add that radio astronomy is about to revolutionize the study of planets outside our own solar system.
Results appear in the journal Nature astronomy.