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Astronomers Have a Pretty Good Idea of Where Planet Nine Might Be

Using various data from the Cassini space probe, scientists are narrowing their search.

ByTim De ChantNOVA NextNOVA Next
ninth-planet-orbit
The orbit of Planet X (orange) is thought to influence the orbits of five objects seen here in blue.

Well, that didn’t take long.

Just last month, astronomers announced evidence of a ninth planet in our solar system beyond Neptune. The frigid world is thought orbit the sun every 10,000 to 20,000 years, which makes the search for the planet a daunting task.

Now, French astronomers—using data gathered by the Cassini space probe while it has been orbiting around Saturn—think they have identified a probable region of space where the planet might be found. Even better, they have crossed off regions where the probability of discovery is low.

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Here’s Bob King, writing for Universe Today:

In a recent paper appearing in Astronomy and Astrophysics, astronomer Agnes Fienga and colleagues looked at what effect a large Kuiper Belt planet would have on the orbits of other planets in the Solar System, focusing their study on Saturn. Thanks to NASA’s Cassini orbiter, which has been orbiting Saturn since 2004, we can precisely calculate Saturn’s position along its orbit.

Cassini is providing other hints as to where this mysterious planet may be lurking. Though the planet is probably quite cold—and therefore gives off very little radiation that can be sensed by ground-based telescopes—it should still be giving off radio waves that the probe can detect.

While we are still probably many years away from the discovery of Planet Nine— if it exists at all , of course—astronomers seem to be making progress at a remarkable pace.

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Image credit: Caltech AMT