A massive object in the vicinity of the Solar System has intrigued researchers
Astronomers using the VLA (Very Large Array) radio astronomy observatory have made a detection of a planetary-mass object, ktory podroChews through space without the company of any parent star. It is located about 20 light years from Earth and has a surprisingly strong magnetic field. Researchers believe it may pomoc to better understand magnetic processes in stars and planets.
– This object is located exactly at the boundary between a planet and a brown dwarf, that is "failed star". Studying this object could potentially help usoc in understanding the processoin magnetic zaroBoth in the stars and on the planets – said study leader Melodie Kao of Arizona State University.
Brown dwarfs are too massive objects to be considered planets, but not massive enough to sustain the nuclear fusion of hydrogen in their nuclei – a process whichory drives stars. Theorists suggested in the 1960s that such objects would exist, but the first detection did not occur until 1995. Originally thought not to emit radio waves, but in 2001, strong magnetic activity was revealed thanks to the VLA.
Subsequent observations have shown that someore brown dwarfs have strong auroras, similar to those observed on the giant planets of our solar system. Auroras observed on Earth are caused by the interaction of our planet’s magnetic field with the solar wind. However, lone brown dwarfs do not have solar wind from a nearby star, with ktorym could interact.
How auroras are formed on brown dwarfs? This is currently unknown, but scientists think one possibility is a planet or moon interacting with the brown dwarf’s magnetic field, as happens between Jupiter and its moon Io.
The strange object, about whichorego was published in „The Astrophysical Journal Supplement Series” has been named SIMP J01365663+0933473. Has a magnetic field more than 200 times stronger than Jupiter. The object was originally detected in 2016, as one of five brown dwarfsoin whichore scientists have studied with the VLA to gain new knowledge about pol magnetic and mechanismow, thanks to ktorym someore of the most interesting objectsow can produce strong radio emissions. The masses of brown dwarfsow are difficult to measure, and woAt the time, the object was thought to be an old and much more massive brown dwarf.
Last year, an independent team ofoł scientistow discovered that SIMP J01365663+0933473 was part of a very young group of stars. Its young age means that it is actually much less massive and mohead to be a free-floating planet 12.7 times more massive and 1.22 times larger than Jupiter.
Having about 200 millionow years the object has a surface temperature of about 825 degrees Celsius. For leekoThe Sun’s surface temperature is about 5500 degrees Celsius. RoThe difference between the planets – gas giants – and brown dwarfs remains hotly debated among theod astronomeroin, but one of the principles thatoThe method used by scientists is mass, below whichorej ends deuterium fusion – about 13 Jupiter masses.
Teamoteam of scientistsoin from Caltech, ktory originally detected the radio emission in 2016, observed it again at even higher radio frequencies, and confirmed that the object’s magnetic field was even stronger than originally measured.
– Such a strong magnetic field poses a huge challenge to our understanding of the dynamo mechanism (Magnetohydrodynamic Dynamo Theory – przyp. red.), whichore produce magnetic fields in brown dwarfs and extrasolar planets and help drive observed auroras – said Gregg Hallinan of Caltech.
– Detection of SIMP J01365663+0933473 by radio emission of aurora means roalso that we may have a new wayob detection of exoplanets, including those thatore not circling aroundoł of the parent star – Hallinan pointed out.