This is what plasma looks like – gas that has been zapped hard enough that it’s now an electrical conductor. Thomas Crooke called it “radiant matter” when he first observed it in the earliest cathode tubes. Astronomers later deduced that this stuff is the most common form of matter in the universe. There are vast clouds of plasma drifting between the stars, glowing eerily in the blackness.
A photo from Wikimedia Commons contributor Blaise Frazier, aka PiccoloNamek.
