When magnetic fields of opposite polarity collide and merge, they unleash a torrent of energy. The process, known as magnetic reconnection, can cause flares on the Sun and magnetic storms and shimmering auroras on magnetized planets with substantial atmospheres, such as Earth, Jupiter and Saturn. Now scientists have discovered that magnetic reconnection also happens on Venus, a planet with no intrinsic magnetic field. The finding, reported today in Science1, suggests that magnetic reconnection may generate auroras on Venus, and could have contributed to the loss of a thick, water-rich atmosphere that scientists believe surrounded the planet during its early history, some 4 billion years ago.
Via Dr. Stefan Gruenwald