NASA Hubble Jellyfish Nebula
You’re not looking at a specimen placed under a microscope, but rather NGC 2022, a jellyfish-like planetary nebula. How do these form? When stars like the Sun grow advanced in age, they expand before glowing red, and then these red giants begin to lose their outer layers of material into space. Since over half of a star’s mass can be shed in this manner, a shell of surrounding gas is formed, while causing the star’s core shrinks and grows hotter, thus emitting ultraviolet light. Read more for a video on nebulae and additional information.

Most planetary nebulae are of vast size, and one that is nearly invisible to the human eye from Earth would appear larger, but no brighter, from close by. However, the Orion Nebula, the brightest nebula in the sky and occupying an area twice the diameter of the full Moon, can be seen with the naked eye, but believe it or not, was missed by early astronomers.