Wonder of ScienceA mesmerizing timelapse of the Sun in ultraviolet light, captured by the SDO spacecraft over the course of a month.
Credit: NASA/SDO
#sun #nasa #space #astronomy
Michael Gemar@wonderofscience @katedaley It’s extremely weird and almost disturbing to me that the Sun has such detailed, non-homogenous structure. It’s supposed to be just a big ball of flamey gas!
Martin Vermeer FCD@michaelgemar @wonderofscience @katedaley It is, but not when you're looking at it in the hard ultraviolet, like here. The solar 'surface' or photosphere at a temp of ~6000K shines in the visible light and cuts off towards the UV. This image shows rarefied, much hotter gases (+ magnetic fields) well above the photosphere, making up the chromosphere and corona. This is where solar activity plays out.
@martinvermeer @wonderofscience @katedaley Isn’t it also the case that stars the size of the sun have convection currents that contribute to its non-homogenous nature?
@michaelgemar @wonderofscience @katedaley Precisely. It is the convection in the outer layers (together with differential rotation) that maintains the magnetic field inside the gas by a natural dynamo process. The wound-up magnetic field lines then rise to the surface in sunspots (which always consist of a N and a S pole), forming the 'arcs' in space you can see in the imagery, made visible by the hot plasma inside them.