The Cat's Eye Nebula or NGC 6543, is a planetary nebula in the constellation of Draco. Structurally, it is one of the most complex nebulae known, with high-resolution Hubble Space Telescope observations revealing remarkable structures such as knots, jets, bubbles and sinewy arc-like features. In the center of the Cat's Eye there is a bright and hot star; around 1000 years ago this star lost its outer envelope, producing the nebula.---Wikipedia
Synapse in Brain Deep inside the brain, a neuron prepares to transmit a signal to its target. To capture that expectant, fleeting moment with painstaking detail, science illustrator Graham Johnson based his elegant, highly accurate drawing on ultra-thin micrographs of sequential brain slices. The brain contains billions of neurons, whose network of chemical messages form the basis of all thought, movement and behavior. Johnson's illustration tells the story of one such millisecond signal.
"Right and left coronary arteries, emerging from the origin of the aorta, veins of the heart and coronary sinus." illustration by J. M. Bourgery from Atlas of Human Anatomy and Surgery / Atlas d'antomie Humaine et de Chirurgie