Astrocyte

Splashery stretches a drumhead over this Splash's outline, twelve inches across, and finds the ways it can ring. Its lowest is 923.3 Hz, 83 cents sharp of A5, the nearest tine on the comb. The next fifteen are its overtones, and each one draws its own figure: sand gathers on the lines that stay still.

Tap it to send a calcium wave out along its arms.

An astrocyte is a star-shaped cell in the brain and spinal cord; its name means "star cell." Astrocytes look after the neurons around them, and the ends of their arms, called end-feet, wrap around tiny blood vessels and help control how much blood flows by.

Astrocytes pass messages to each other with waves of calcium, which scientists can watch with dyes that glow. Tap it to send one: a front of green light spreads from the middle out along every arm to the end-feet, and the blood vessel they hold widens for a moment. Faint waves pass by themselves now and then.

Made in Splashery. Its code is MIT.

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