Aurora is the light emitted by ionized particles in the upper atmosphere of the earth. This phenomenon exists in the atmosphere of other planets except mercury in the solar system, even the satellites of Jupiter, Ganymede and Europa. However, scientists have never detected the comet Aurora before, but the latest observation data analysis of Rosetta detector shows that far ultraviolet Aurora radiation is emitted around comet 67p. “I’ve been studying the aurora for 50 years, and it’s amazing and fascinating to find the aurora near comet 67p, which has no magnetic field,” said Jim birch, a physicist at the Southwest Research Institute Aurora are produced by the stimulation of charged particles in the atmosphere. On earth, the solar wind blows into the magnetosphere and interacts with the charged particles in the magnetosphere. These charged particles drop like raindrops into the upper atmosphere and travel along magnetic lines to the poles, where they form a ripple like light curtain. However, the aurora of Ganymede and Europa are produced by the interaction of Jupiter’s magnetic field. So far, scientists have not found that Venus itself cannot form a magnetic field, but its interaction with the solar wind produces a magnetic field strong enough to form aurora. The atmosphere of Mars is very thin, but its weak magnetic field can produce aurora. Jupiter’s permanent aurora is not caused by solar wind, but from some mysterious mechanism that needs to be discovered urgently. < / P > < p > although the auroral rings of Saturn seem to be generated by the solar wind, the formation of some aurora is unpredictable, which is still an unsolved mystery. Comet 67p doesn’t even have a “borrowed” magnetic field, but this comet has an atmosphere, a gas shell called a coma, which sublimates ice when an active comet is close enough to the sun. < p > < p > < p > < p > < p > the far ultraviolet spectrometer of the Rosetta detector Alice instrument detected the far ultraviolet glow in the comet 67p, and the ion and electronic sensors (ies) of the Alice instrument detected a greater surprise discovery – electrons from the solar wind. At first, we thought that the ultraviolet radiation emitted by comet 67p was a phenomenon called “daylight”, which was the result of the interaction between solar photons and comet gas, said Joel Parker, an astronomer at Southwest Research Institute. We were surprised to find that ultraviolet radiation is Aurora, but not driven by photons, but by electrons in the solar wind. The solar wind breaks down water and other molecules in the coma and accelerates in the environment near the comet. < / P > < p > the team simulated a comet with a faint escaping gas and found that the interplanetary magnetic field surrounding the comet was enough to provide a path for accelerating solar wind electrons to enter the potential well generated by the electric field around the comet core. However, because comet 67p has no magnetic field, its aurora are diffuse, which is in sharp contrast to the “closed Aurora” formed by solar wind stimulation on earth and Mars. The acceleration and excitation of comet 67p’s aurora makes the phenomenon unique to the solar system, the researchers said. < / P > < p > the discovery may provide new clues for understanding how aurora are generated in the entire solar system, but comet aurora can be used as a tool for understanding space meteorology. By detecting the glow of the sun at different distances, astronomers can learn a lot about the changes of electrons in the solar wind. At present, the latest research report is published in the recently published journal of natural astronomy. Global Tech

By ibmwl