Proplyds

“Tadpoles” swim through the Orion Nebula, a giant stellar nursery more than 1300 light-years from Earth. Like tadpoles, they’re not yet fully mature. Also like tadpoles, not all of them will survive their hostile environment.

The tadpoles are known as protoplanetary disks – proplyds for short. They’re giant “cocoons” of gas and dust. Each one envelops a central star that’s still being born. And some of them may give birth to planets.

The proplyds look like tadpoles because they’re being sculpted by the radiation of nearby stars. The stars are exceptionally hot and bright. They produce a lot of ultraviolet radiation. The UV acts like a blowtorch, blasting the proplyds. The side of a proplyd that faces the stars is hot and bright, so it forms the “head” of the tadpole. The “tail” is formed by gas flowing away from it.

The proplyds are quite young – no more than a couple of million years old. Their central stars are still taking shape. Many of them shoot out “jets” of hot gas from their poles that are billions of miles long.

A disk of cooler gas and dust may surround the infant star. If it survives the blowtorch, the disk may give birth to planets – worlds born from the remains of stellar tadpoles.

The Orion Nebula is visible to the unaided eye. It looks like a wide, fuzzy star in Orion’s Sword. Orion is in the east and southeast at nightfall, with the sword to the right of its three-star belt. 

Script by Damond Benningfield

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