Update
THE LATEST INTELLIGENCE
Planetary scientists Konstantin Batygin and
Mike Brown of Caltech think there could be a
ninth planet in the Solar System. How did they
make this discovery?
I wouldn’t say it’s a discovery yet. They’ve found
strong evidence of gravitational disturbances on
some of the furthest objects in the Solar System.
The disturbances may be caused by an object with
around 10 times the mass of Earth – more or less
the size and mass of Neptune. Large bodies
beyond Neptune have been hypothesised since
the 1980s. There were suspicions of somethingthere but it was never confirmed. Positive
confirmation would be to take a picture of Planet
Nine, and that would be extremely difficult.Why would it be so difficult?
Because it’s so far away. Neptune is the furthest
proper planet and is 30 times further away from
the Sun than Earth [from the Sun to Earth is one
astronomical unit (AU)]. From there up to 100 AU is
the Kuiper Belt containing Pluto and the other
‘trans-Neptunian objects’. Their orbits are
extremely tilted and elliptical – they go very far
away, come a bit closer and then go far away
again. This is the main reason why they’re not
considered proper planets, because their orbits
are different to the orbits of the other planets.
‘Planet Nine’ is expected to be at a mean distance
of 700 AU, in a region between the Kuiper Belt and
the Oort Cloud, which extends for thousands of
AUs and is where most comets originate.How could it be done?
There are plans to use the largest telescopes in
the world, like the Keck or Subaru, on top of the
Mauna Kea volcano in Hawaii. But even takingRIGHT: Mike Brown (left) and
Konstantin Batygin believe
there could be a ninth planet
in the Solar System PHOTOS: CALTECH/ R HURT/ IPAC, GETTY, SCIENCE PHOTO LIBRARYCOULD THERE BE A HUGE NINTH PLANET IN THE SOLAR SYSTEM?
WE ASKED DR FRANCISCO DIEGO, SENIOR TEACHING FELLOW IN
UCL’S DEPARTMENT OF PHYSICS AND ASTRONOMY, WHETHER
THERE IS SOMETHING OUT THERE...?
PLANET NINEBEHIND THE HEADLINES“I WOULDN’T SAY IT’S A DISCOVERY YET.
THEY’VE FOUND STRONG EVIDENCE OF
GRAVITATIONAL DISTURBANCES ON
SOME OF THE FURTHEST OBJECTS IN
THE SOLAR SYSTEM”