The space telescope Hubble captured stunning images of a phenomenon scientists call a “stellar volcano”. Photos capture what happens in the star R Aquarii with violent explosions ejecting matter around the star. The term stellar volcano was coined because the phenomenon appears to cause matter to be ejected in a manner similar to the way lava is ejected from the Earth’s interior.
R Aquarii is not a single star, but a symbiotic variable star consisting of a red giant and a white dwarf orbiting each other in an eternal cosmic dance. The red giant pulses, with temperature and brightness changing over a period of 390 days. This intersects with the white dwarf’s 44-year orbital period. As the white dwarf begins to approach the red giant, it sucks in some of its gas through gravity and piles the disk around it until it collapses and explodes, expelling jets of material. Then the cycle starts again.
“This explosion ejects powerful jets that appear as filaments ejected from the binary system, forming loops and trails as the plasma emerges in the form of streamers. The plasma is twisted by the force of the explosion and channeled upward and outward by strong magnetic fields. The flow appears to curve in on itself in a spiral pattern. The filaments glow in visible light because they are activated by bubbling radiation from the twin star R Aquarii,” report the scientists overseeing Hubble’s operation.
The nebula surrounding the binary star is known as Cederblad 211 and may be the remnant of a stellar supernova explosion.
Naftemporiki.gr