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FOUND: The Largest Solar System Ever Discovered

An artist’s impression of one very lonely planet (Image: University of Hertfordshire/Neil James Cook)

Imagine if a year lasted 328,725,000 days.

On the gas giant planet 2MASS J2126−8140, one year—that is, one orbit of the planet around a star—lasts about 900,000 times longer than an Earth year. Which makes this gas giant planet the far edge of the largest solar system ever discovered

It’s so large that the planet is one trillion kilometers, or 6900 astronomical units (AU), away from its star, a distance about three times larger than the separation of any previous far-flung star-planet pair. Though both the star and the planet had been discovered in the past decade, astronomers had not thought that they were connected in any way.

The planet is somewhere between 10 and 45 million years old, which, as points out, means that it has completed, at most, 50 orbits so far.

From that planet, it’d be hard to distinguish which star was the one keeping you in orbit; it’d appear just like any other twinkling star in the sky, perhaps a bit brighter than the others, but not much.

All this makes the possible Planet Nine in our own solar system, which would be 200 AU from the sun and take 15,000 Earth years to make one orbit, seem like a rather close neighbor.

Bonus finds: A cuddly kinkajou, mammoth bones, $70,000 worth of stolen cheeseEichmann’s pardon plea

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