Stellar jets like
What happens here ? The physics is quite different. Electrons are emitted from the whole surface of the sphere as in all other cases. But since the gas is dense, so that the electrons are slowed down through collisions after a few centimetres. They are then trapped by the local magnetic tube and driven to northern or southern ovals : they come back toward the star from which they were ejected. Close to magnetic poles, their density becomes high enough so that emissions due to collisions become visible, looking like stellar jets : the star feeds itself with its own stellar wind.
The discovery of stellar jets dates from the late twentieth century, and their physical condition is still uncertain. There are very few photographs of stellar jets : the stars that produce them are too far away to be seen with good accuracy. However, a NASA satellite, Chandra proposes some pictures. It is assumed that an intense magnetic field (a Magnetar) could produce high currents (larger than a thousand amperes) and generate jets. But nothing has been established yet ...
Updated on 17 septembre 2021