“Our sun is now a pretty mild middle-aged star, but many other stars produce enormous flares that can threaten the habitability of any planets that may orbit them”, Hallinan said in the email. “If you are working in brown dwarves, it matters whether you think of them as small stars or big planets”, Littlefair opined. They theorized the same thing was happening on this brown dwarf. This makes them give off light.
Advertisement
Brown dwarfs are relatively cool, dim objects that are difficult to detect and hard to classify.
These substellar objects possess varieties in masses and temperatures. Io is “plowing” through Jupiter’s magnetosphere, generating voltages that spur on the planet’s aurora, Hallinan said.
The auroras were found in the atmospheres of several failed stars called brown dwarfs. So the question you might ask: “is a brown dwarf more like a planet or more like a star?” “We already known from observations of brown dwarves that they have clouds in the atmosphere”. It was initially thought that the waves were produced in much the same way as signals from other stars – in an extremely hot upper atmosphere or “corona” that is heated via magnetic activity occurring in the lower atmosphere. Based on their various measurements, the authors estimate that the magnetic field strength in the region is at least 1,500 Gauss, and could be double that (for comparison, the Earth’s magnetic field is about half a Gauss). It is possible, scientists say, that the brown dwarf strips itself of materials and charged particles necessary for auroras.
To figure this out, Hallinan and his research team analyzed one brown dwarf in particular – LSRJ 1835+3259.
While in graduate school, in 2006, Hallinan discovered that brown dwarfs can actually pulse at radio frequencies.
“Seeing auroral signature in a strongly magnetized object outside of our solar system is groundbreaking, but not too surprising”, Hampton said. Previously, the auroras of Jupiter had been the brightest ones observed.
Astronomers made the discovery after combining radio and optical observations of the object, which is 18 light years from Earth.
According to BBC, the aurora was found around a brown dwarf that scientists called LSR J1835.
The spectacular light show is the first confirmed aurora on a body outside the solar system, and the most powerful ever recorded. Earth is not an exception, with its northern and southern lights. “Well this brown dwarf has aurorae that are at least 10,000 times more powerful than Jupiter’s aurora”. That discovery led him to speculate that those radio emissions could be caused by auroras.
In our solar system, only Mars and Venus do not have magnetic fields, therefore no aurora.
Exoplanet hunters often speak of “Goldilocks” planets, positioned just the right distance from their stars to have liquid water on their surface to harbor life.
Advertisement
[NASA estimates 1 billion “Earths” in our galaxy alone].
