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First close-up image of Pluto's moon Hydra reveals its awkward shape


One of Pluto's elusive moons is finally coming into view. NASA released the very first up-close image of Pluto's known outermost moon Hydra, giving us our first taste of the space rock's shape. And it's an awkward one.

Up until now, images of Hydra have been very small and blurry. This latest image was taken on Monday July 13th at 7:16PM ET from about 400,000 miles away. Its resolution is about 2 miles per pixel, and the image is the first really clear photograph we've received yet of Hydra. NASA will release an even better-resolution Hydra pic Friday July 17th.

It’s about a third larger on one side than the other

The photo reveals that Hydra is 28 miles wide by 19 miles long; also, it’s about a third larger on one side than the other. The surface shows variation in brightness, which suggests that Hydra’s outer layer is composed primarily of water ice, according to New Horizons team member Hal Weaver.

Researchers know very little about Hydra's size and composition. A recent study in Nature based on Hubble data suggested that Hydra tumbles about Pluto and its larger moon Charon like a football. These upcoming images should give us a better idea of what Hydra is made of, unraveling the mystery around this faraway moon.