March 22, 2023

Unexpected Radio Signals From Distant Stars Suggest Hidden Planets

Using the worlds most effective radio antenna, researchers have found stars unexpectedly blasting out radio waves, potentially showing the presence of hidden worlds.
The University of Queenslands Dr. Benjamin Pope and coworkers at the Dutch nationwide observatory ASTRON have actually been browsing for worlds using the worlds most effective radio telescope Radio frequency Array (LOFAR) positioned in the Netherlands.

” Weve discovered signals from 19 distant red dwarf stars, 4 of which are best discussed by the existence of planets orbiting them,” Dr Pope said.
” Weve long known that the planets of our own solar system produce effective radio waves as their electromagnetic fields communicate with the solar wind, but radio signals from planets outside our planetary system had yet to be chosen up.
” This discovery is an essential action for radio astronomy and could possibly cause the discovery of worlds throughout the galaxy.”
Formerly, astronomers were just able to spot the really nearest stars in consistent radio emission, and whatever else in the radio sky was interstellar gas, or exotica such as black holes.
Now, radio astronomers are able to see plain old stars when they make their observations, and with that info, we can look for any planets surrounding those stars.
The team concentrated on red dwarf stars, which are much smaller than the Sun and understood to have extreme magnetic activity that drives outstanding flares and radio emission.
However some old, magnetically inactive stars likewise appeared, challenging traditional understanding.
Dr. Joseph Callingham at Leiden University, ASTRON and lead author of the discovery, said that the group is confident these signals are coming from the magnetic connection of the stars and unseen orbiting planets, similar to the interaction in between Jupiter and its moon, Io.
” Our own Earth has aurorae, frequently acknowledged here as the northern and southern lights, that also produce effective radio waves– this is from the interaction of the worlds electromagnetic field with the solar wind,” he stated.
” But in the case of aurorae from Jupiter, theyre much stronger as its volcanic moon Io is blasting material out into space, filling Jupiters environment with particles that drive uncommonly powerful aurorae.
” Our model for this radio emission from our stars is a scaled-up version of Jupiter and Io, with a world covered in the electromagnetic field of a star, feeding product into huge currents that likewise power bright aurorae.
” Its a spectacle that has actually attracted our attention from lightyears away.”
The research study group now wished to verify the proposed worlds do exist.
” We cant be 100 percent sure that the 4 stars we think have worlds are indeed world hosts, however we can state that a planet-star interaction is the best description for what were seeing,” Dr. Pope said.
” Follow-up observations have actually dismissed worlds more huge than Earth, however theres absolutely nothing to say that a smaller sized world would not do this.”
The discoveries with LOFAR are simply the start, but the telescope only has the capacity to keep an eye on stars that are relatively close by, as much as 165 lightyears away.
With Australia and South Africas Square Kilometer Array radio telescope lastly under building and construction, hopefully switching on in 2029, the group predicts they will have the ability to see numerous appropriate stars out to much higher distances.
This work shows that radio astronomy is on the cusp of transforming our understanding of worlds outside our Solar System.
” The population of M dwarfs observed at low radio frequencies” by J. R. Callingham, H. K. Vedantham, T. W. Shimwell, B. J. S. Pope, I. E. Davis, P. N. Best, M. J. Hardcastle, H. J. A. Röttgering, J. Sabater, C. Tasse, R. J. van Weeren, W. L. Williams, P. Zarka, F. de Gasperin and A. Drabent, 11 October 2021, Nature Astronomy.DOI: 10.1038/ s41550-021-01483-0.
” The TESS View of LOFAR Radio-emitting Stars” by Benjamin J. S. Pope, Joseph R. Callingham, Adina D. Feinstein, Maximilian N. Günther, Harish K. Vedantham, Megan Ansdell and Timothy W. Shimwell, 11 October 2021, The Astrophysical Journal Letters.DOI: 10.3847/ 2041-8213/ ac230c.