There's another new planet outside our solar system? Yawn...
Since 2010 we found about 100 new exoplanets a year
and as the list grows
these discoveries seem less and less interesting.
To help exoplanets get their groove back,
we looked for the coolest, weirdest and most extreme.
I'm Sophie and welcome to The Countdown.
Our Earth is a blue planet where it rains water.
HD 189773b is a blue planet where it reins glass.
Sideways!
Earlier this year the Hubble space telescope
detected a blue exoplanet 63 light years from our own.
The hue of HD 189773b is darker than Earth's
and the difference don't end there.
The exoplanet is a gas giant like Jupiter
and it's much closer to its sun.
This boosts the average temperature to a scorching 1000 degrees Celsius,
but on the dark side of the planet
it can be hundreds of degrees cooler than the sunny side.
This change in temperature creates enormous turbulence in the atmosphere,
winds up to 7000 Km/h toss around particles of silicate,
the material that makes up sand,
and they may form grains of glass
as they rain sideways through their extreme environement,
reflecting the star light and providing their planet's dark blue colour.
If glass doesn't impress you,
perhaps you prefer more sparkling material
like diamonds!
55 Cancri-e is a rocky world called a Super Earth,
twice as large as our own planet,
with 8 times as much mass
and, according to a 2012 study,
the planet contains a layer of graphite and diamond
just below the surface.
Beneath that mixture, there is an even thicker layer
containing mostly pure diamond.
Altogether these materials make up 1/3 of the exoplanet's mass.
But before you decide to travel 40 light years to the glittery super earth,
check out some more recent research.
A new paper found the ratio of carbon to oxygen
in the host star is lower than expected.
If the planet's makeup resembles its parent star
it won't have the carbon needed to make up diamonds.
So much for my dreams of a celestial jewelry store.
If we travel even farther away from Earth,
things get even more backwards. Literally.
More than 1000 light years away
the planet HAT-P-7b is orbiting its star in the wrong direction.
Most planets orbit in the same direction that their host star spins,
but in 2008 astronomers discovered an exoplanet the size as Jupiter
traveling in the opposite direction.
The backwards motion remained a mystery until last year
when researchers detected a second star and an outer planet
in the same system as HAT-P-7b.
The gravity of these neighbours could be responsible
for the exoplanet's unusual orbit.
According to the study, the companion star
tugs on the newly discovered outer planet
tilting its orbit.
This tilt then affects the orbit of HAT-P-7b.
If the researchers are correct,
their theory could also explain unusual orbits in other systems.
Earth has a hefty 4.5 billion years under its belt
but that's nothing compared to the oldest known exoplanet
PSRB1620-26b, more comfortably known as the Methuselah Planet
is a whopping 13 billion years old
which means that formed less than a billion years after the Big Bang
Methuselah orbits a binary system made up of a pulsar and a white dwarf.
According to a 2003 study, it's probably a gas giant,
two and a half times as massive as Jupiter
But when it was first discovered in 1994
Scientists thought it was a small star.
In the type of ancient star collection when Methuselah lives,
it was considered impossible for planets to form.
This exoplanet is located thousands of light years from Earth
in a so called globular cluster.
Astronomers used to think globular clusters
didn't have enough heavy elements to make planets,
but Methuselah proves planets are hardier than expected,
capable of forming early in the Universe's history from limited materials.
Reflected light makes exoplanets visible
and give Earth its blue hue
but 750 light years from our pale blue dot
there's a pitch black world
that reflects only 1% of the light hitting it.
[Star Wars' Imperial March]
No, it's not the Death Star. It's a real planet.
And as of 2012 is the darkest planet we've ever discovered.
And we're not sure why.
If you saw TrES-2b up close it would be blacker than coal
but with a slight red glow.
It orbits close enough to its star to heat up to a toasty 980º Celsius.
But when it passes in front of that star
it doesn't significantly dim the light.
Computer models suggest Hot Jupiters like TrES-2b
shouldn't be any darker than Mercury
which shines 10 times brighter.
How does this exoplanet manage to stay inky?
A high concentration of chemicals like sodium and titanium oxide
in the atmosphere could be absorbing the light,
but researchers suspect there's another more mysterious phenomenon happening.
Who knows?
These dark worlds may represent a whole new category of planets
(Music)
And that's your Countdown
Links to all of these stories are in the description below.
Also, don't forget to visit the Spacelab channel on youtube and subscribe.
For Scientific American,
I am Sophie Bushwick
and I'm holding up for an exoplanet that comes with aliens,
ideally aliens that look like puppies.
(Laughing)
(Music)