Discovered: A massive super-planet 13 times larger than Jupiter

Say hello to Kappa Adromedae b, a world so big it defies conventional classification

An artist's rendering shows "super-Jupiter," formally known as Kappa Andromedae b.
(Image credit: NASA's Goddard Space Flight Center/S. Wiessinger)

Scientists have snapped a photo of a rare alien exoplanet that's 13 times bigger than Jupiter and 170 light-years away. Officially named Kappa Adromedae b ("Kappa And b," for short), the massive world blurs distinctions between planets and small stars, spurring scientists to simply dub it a "super-Jupiter." Here's what you should know about the gigantic world:

What is Kappa And b exactly?

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Why is it so difficult to classify the exoplanet?

Because the unique planet is so large and hot. "According to conventional models of planetary formation, Kappa And b falls just shy of being able to generate energy by fusion, at which point it would be considered a brown dwarf rather than a planet," said NASA's Michael McElwain through an official release. "But this isn't definitive, and other considerations could nudge the object across the line into brown dwarf territory."

How did scientists capture photos of Kappa And b?

Taking photographs of far-off planets isn't easy. Of the 850 known planets, fewer than a dozen have ever been photographed, says Joanna Carver at New Scientist. Part of the difficulty is that the glare from host stars can conceal the light given off by a nearby planet. "It's kind of like seeing a firefly next to a lighthouse," says Joseph Carson, an assistant professor of astronomy at the College of Charleston in South Carolina. In this case, researchers had to remove the light from Kappa And b's parent star with digital software, which revealed the big, bright super-Jupiter orbiting around it.

What does it mean for our understanding of the galaxy?

The discovery of Kappa And b shows that "large stars are capable of producing exceptionally large planets," says George Dvorsky at io9. Plus it indicates that these planets can anchor a parent star at greater distances than our own solar system. "This planetary system is very different form our own," says Thayne Currie of the University of Toronto, who co-authored the study.

Sources: io9, NASA, New Scientist, The Register