BIG, STRONG AND ALL ALONE: Researchers find solitary 'rogue planet' larger than Jupiter, wandering just 20 light-years away
A strange rogue giant planet has been spotted roaming around our galaxy just 20 light-years away from our solar system. A rogue planet is one that does not orbit a star.
A study published recently stated that this rogue giant has an extremely strong magnetic field more than four million times stronger than that of Earth. The planet is also able to generate brilliant auroras that would shame the ones at the Earth's poles. These observations were made using the National Science Foundation's Karl G. Jansky Very Large Array (VLA), and are the first radio observations of a body outside of our solar system; it is also the first time that researchers have been able to measure the magnetic field of a celestial body like this.
The object was named SIMP J01365663+0933473, or SIMP for short, when it was first discovered in 2016. Scientists at the time presumed the object was a brown dwarf, which is a celestial body too big to be a planet, but too small to be a star. A study conducted in 2017, however, showed that the body just about reached the specifications required for it to be termed a planet, even though it is 12.7 times the mass and 1.2 times the radius of Jupiter, reported Astronomy.com.
Arizona State University's Melodie Kao, who led the new study on SIMP, said in a press release: "This object is right at the boundary between a planet and a brown dwarf, or ‘failed star,’ and is giving us some surprises that can potentially help us understand magnetic processes on both stars and planets."
Unlike most planets, however, SIMP is very hot. The surface temperature on the planet is over 1,500 F (825 C), comparable to Venus in our own solar system, where the average temperature on the surface is around 875 F (470 C).
SIMP does not orbit a star and so the high temperatures on its surface are probably from its formation, about 200 million years ago. The massive planet will lose most of this heat over time.
The planet's magnetic field is millions of times stronger than that of Earth. SIMP is also able to produce dazzling aurora displays that are not generated the same way they are on our planet.
In our solar system, Jupiter has the strongest magnetic field, which is almost 20,000 times stronger than Earth's. This is why the gas giant is able to produce auroras that are extremely bright and spectacular to watch. The light shows happen when particles charged by electricity are accelerated along the magnetic field lines of the planet before they crash into the upper atmosphere of Jupiter at around 3,000 miles (5,000 kilometers) per second.
We have a similar process that takes place on Earth creating what we call Northern and Southern Lights or Aurora Borealis and Aurora Australis. On Earth, the charged particles that create auroras come from the Sun in the form of solar winds, but on Jupiter, the particles come mainly from its moon Io. Because SIMP is a planet that does not have a star, scientists believe its auroras are produced in a similar manner to Jupiter's. This means that SIMP probably has a moon creating the auroras.
Kao said: "This particular object is exciting because studying its magnetic dynamo mechanisms can give us new insights on how the same type of mechanisms can operate in extrasolar planets. We think these mechanisms can work not only in brown dwarves, but also in both gas giant and terrestrial planets."
Even though this new planet will help researchers gain a better understanding of how magnetic fields are created on exoplanets, that is not all they are researching. Co-author of the study, Gregg Hallinan of Caltech, said: "Detecting SIMP J01365663+0933473 with the VLA through its auroral radio emission also means that we may have a new way of detecting exoplanets, including the elusive rogue ones not orbiting a parent star."