Two scientists claim that they have found
the best evidence yet that a huge ninth planet
exists at the outer limits of the Solar System.
It’s called Planet X, and it’s about 10
times the mass of Earth, or roughly the size
of Neptune.
The planet supposedly orbits far out from
the Sun on a highly elliptical path, which
takes 10- to 20,000 years to make one full
circuit.
And it's way out there too — somewhere between
200 and 1,200 times the distance from the
Sun to Earth.
But don't get too excited yet — no one has
actually seen this planet.
The entire argument about its existence is
theoretical.
It's based on the observations of six objects
in the Kuiper Belt, the cloud of icy bodies
at the edge of the Solar System.
The way these objects move around the Sun
seems to indicate that they're being affected
by something big.
AKA Planet X.
That's about all the evidence we have though.
Some experts think that six objects is a small
sample for such a big claim.
Also, the researchers say the chances of this
all being a coincidence are 1 in 150,000.
Those are pretty good odds but usually scientists
like to have a way lower probability of failure
— around 1 in 1.7 million.
Still, experts agree that the models supporting
Planet X are strong.
And we've used this indirect method to find
planets before.
Neptune was originally detected by observing
anomalies in the movement of Uranus.
Plus, having a huge planet like this so far
out from the Sun isn't exactly out of the
ordinary.
Planets of this size are very common in the
Universe, so Planet X would make our Solar
System much more normal than strange.
Now all we need to do is find it.
The Large Synoptic Survey Telescope in Chile
or the Subaru telescope in Hawaii may be sensitive
enough to pick up it up.
But until this long lost world is actually
found, Planet X is only an exciting theory.
