• Rogue planets, pink planets and planets made of diamond - that’s only some of the
15 Strangest Planets that exist today.
15 – Planet 9 • In 2016 scientists introduced the idea
that another planet may have entered our solar system.
• Called “planet 9” it is likely a ‘rogue planet’, this is any planet that isn’t
tied to a star, but roams the galaxy on its own.
• It could have been caught by the gravitational forces of the Milky Way and may be orbiting
somewhere beyond Pluto.
• If Planet 9 does exist it could be 10 times the mass of Earth and take 15,000 years
to orbit the sun.
14 – Gliese 581C • Originally thought to have the potential
for possessing water, Gliese 581c is now considered outside this ‘habitable zone’.
It is much too close to its star to support life.
• 581c is also ‘tidally locked’ so it doesn’t have a regular day/night cycle.
This means that as the planet orbits its star, only one side faces star.
So the other side is always in darkness and likely freezing.
• As part of a competition a digital time capsule was selected and sent to Gliese 581c.
It will probably reach there in the year 2029.
13 – TrES-2b • The darkest planet yet discovered is known
as TrES-2b.
• This is because it only reflects up to 1 per cent of the light from its nearby star.
This is makes it darker than the blackest coal.
• About the size of Jupiter, Tres-2b doesn’t have the reflective clouds that Jupiter does.
• It is thought the planet may emit a faint red glow, from the intense heat of its atmosphere,
since it orbits very close to its star.
12 – Methuselah 1620-26 b • The official name of the oldest planet
yet discovered is 1620-26 b but it goes by the nickname “Methuselah”.
• It is thought to have formed around 13 billion years ago - only 1 billion years after
the universe was formed, which isn’t a long time by space standards.
• Methuselah, which is located in the Scorpius constellation, was also the first planet found
orbiting two stars, one of which is a pulsar star.
• Pulsar stars are what remain after a star explodes.
11 – J1407 b • Described as a “Super Saturn”, J1407
b is bigger than Jupiter and its rings are 200 times the size of Saturn’s.
• It has over 30 rings and each of them are millions of miles apart, making the rings
120 million miles across in total.
• The rings are so large that if they replaced Saturn’s rings they would appear bigger
than the moon in the night sky.
• The planet itself is big enough to possibly posses a moon the size of Earth or Mars.
10 – Osiris – HD 209458b • HD 209458b, takes it nickname from the
Egyptian God of the Underworld, Osiris.
This is appropriate since it orbits so close to its star that it has a surface temperature
of 1000C.
• Osiris’s orbit is so close in fact that a year only lasts 3.5 Earth days.
The radiation from the star is also causing its atmosphere to evaporate.
• Apart from its close orbit, Osiris was also the first exoplanet discovered using
the transit method in 1999.
• Since it is so far away scientists can observe its atmosphere when it passes in front
of its star.
9 – 55 Cancri e • 55 Cancri e was discovered in 2004 and
considered a ‘super-Earth’ – it’s about twice the width of our home planet.
• This doesn’t mean that it’s anything like earth, or that it can support life.
In fact it orbits closer to its star than Mercury does to the sun.
• One of it’s sides is always facing it’s star, while on the other side it’s always
night.
• After observations in 2012 scientists thought the crust of the planet might be made
of carbon in the form of diamond.
8 – HD 18977 3b • Back in 2005 the planet HD 18977 became
the first extra solar planet that we knew the colour of.
Through study it was found to be a deep blue colour.
• This colour doesn’t come from any oceans but from the clouds in its atmosphere.
• The planet’s weather is extreme, with winds that blow faster than the speed of sound
and rain that is made of molten glass.
• HD 18977 is considered a ‘hot Jupiter’ with a mass even larger than Jupiter.
7 – WASP-17b • WASP-17b is the puffiest planet that we
know of.
What makes it puffy?
It’s the second largest exoplanet discovered, but it’s only half the mass of Jupiter.
• It’s twice the size of Jupiter but nowhere near the same density; so it’s basically
like a Styrofoam planet.
• As well as being puffy, WASP-17b also orbits its star backwards.
Usually planets travel in the same direction that the sun spins – but not this planet.
• This could have happened when it collided with another planet, which could also be the
cause of its ‘puffiness’. 6 – PSR J1719-1438 b
• PSR J1719-1438 b is the companion of a neutron star, which goes by the same name
– minus the b.
• The amazing thing about these two is that it only takes a little over 2 hours for the
planet to orbit its star.
• This is because it orbits a neutron star, which is extremely dense: it has a greater
mass than our sun yet it is only 20km wide.
That means a teaspoon of this star would weigh a billion tons.
• Its companion planet is also very dense.
A little bigger than Jupiter, it has 20 times the density.
5 – Kepler-10c • Some have called Kepler 10c the ‘Godzilla’
planet, and at more than twice the size of Earth it is large.
• But that’s not what makes this planet special; normally a planet that large would
be gaseous like Neptune.
• However scientists confirmed that this massive planet was actually made of rock.
It was so unusual that it gained the title of “mega-Earth”.
• Although it couldn’t support life, Kepler 10c is older than scientists thought rocky
planets could be, which means there are more habitable possibilities out there!
4 – Kepler 10b • Kepler 10b was the first rocky world discovered
by the Kepler Spacecraft, which was sent in to space to monitor the Milky Way Galaxy and
hopefully find other planets in the habitable zone.
• Even though Kepler 10b is not in that zone it was still an interesting discovery.
This planet is far from hospitable – it lies 20 times closer to its star than Mercury
does to the Sun.
• It reaches temperatures of 2500 degrees Fahrenheit.
That’s hotter than lava.
• Kepler 10b takes less than a day to orbit its star and is 1.4 times the size of Earth,
making it the smallest exoplanet discovered at the time.
3 – Epsilon Eridani b • Epsilon Eridani is the 10th closest star
to Earth, but the closest star with a planet orbiting it.
The star is visible in the night sky, and is only 10.5 light years away.
• The orbiting planet, known as Epsilon Eridani b, is larger than Jupiter and takes
7 years to complete its orbit.
• First discovered back in the year 2000, Epsilon has been used as a science fiction
setting, including as the home to the Babylon 5 space station.
• The planet was recently given the name Aegir.
2 – GJ-504b • GJ-504b has been called the ‘pink planet’
since it still glows from its formation around 150 million years ago, which is young by astronomical
standards.
• It is likely more a magenta than the colour of bubble gum, but this planet is a mystery
to scientists in other ways.
• For a gas giant, it is much further from its star than previously thought possible.
The planet was also the smallest to have its image captured, when the Subaru Telescope
in Hawaii observed it.
• Its parent star is visible in the sky and was discovered in 1598 by a Danish nobleman
and astronomer.
1 –16 Cygni Bb • 16 Cygni Bb is a ‘Tatooine’-like planet
since it is part of a system with three stars.
• Discovered in 1996 in the constellation Cygnus, meaning swan, the planet was found
to have one of the strangest orbits.
• Instead of orbiting in a circular shape around the central star, Cygni Bb gets to
within 25 million miles then swings out to 200 miles away from its star.
• When it’s closest to the star, the temperature reaches 1400 degrees Fahrenheit, then drop
to minus 430 degrees at its furthest.