Are they something like coronal mass ejections from the Sun? At https://phys.org/news/2021-06-classical-nova-explosions-involve-jets.html … we learn that researchers at Oxford University have discovered that nova explosions are accompanied by ejections of jets of oppositely charged hot gas and plasma. This persists for years in the aftermath of such cosmic explosions. Previously, such jets had been encountered emmitted from black holes and collapsing stars. What is the connection with CMEs?
Nova's are explosive events – and supernovas are the brightest. When they erupt the star, or cosmic object, suddenly brightens – by many orders of magnitude. However, the mainstream theory is still kicking and the researchers are currently unable to remove themselves from this stricture – as the main body of the article seems to show. They invoke thermonuclear explosion as the source of the plasma.
At https://phys.org/news/2021-06-variable-emission-milky-supermassive-black… … the supermassive black hole at the heart of the Milky Way is the subject of discussion [and research]. These radiate energy across the electromagnetic spectrum. The black hole in our galaxy, we are told, often flares. The mainstream theory is that this occurs when black holes are accreting material – gobbling up stars, dust and gases.
At https://phys.org/news/2021-06-astronomers-giant-center-galaxy.html … astronomers spot a 'blinking giant' near the centre of the Milky Way – a star displaying brightness that sometimes dims. Is it pulsating or is it simply another cosmic body orbiting the star and obscuring on a temporary basis its light.