Back in 2010, this was the clearest image of Pluto ever taken.
It was captured by the Hubble space telescope and as you can see,
reveals very little about the icy dwarf planet. At this point in time, Pluto was just a distant
object that looked like a mottled orange, white and black world with a mysterious bright spot.
But, just 5 years later, the once ninth planet of the solar system, became more than just a smear
of light, because, in 2015, the incredible New Horizons spacecraft silently passed by,
aiming all of its scientific instruments at the icy world, and its five strange moons.
New Horizons could only spend a few hours visiting Pluto, before continuing on its
journey through a region called the Kuiper belt. But during this brief encounter,
it sent back some of the most spectacular images ever captured of an object in space.
Pluto is covered in fascinating features as these amazing images reveal, but the one that
stands out the most, is, of course, its enormous, frozen, heart. A familiar shape on an alien world.
So what is this bizarre feature? And how did it form? Well, to really explore the
heart of Pluto properly, we are going to need a super science fiction space suit,
a suit that will protect us as we explore some of the most devastating places in the solar system,
places that were never meant to be visited by any human being.
Before you embark on this dangerous mission, remember,
this is an extreme environment. The surface temperature can drop to a blisteringly cold -400
degrees Fahrenheit, which is -240 degrees Celsius. There is no oxygen here, just a thin layer
of nitrogen, methane and carbon monoxide gas that creates an atmospheric pressure,
about 100,000 times weaker than on Earth. And not only that, it changes depending on
how close pluto is to the sun, collapsing when it is at its furthest point away.
Between the extreme cold, low atmospheric pressure and constant changes, Pluto's surface is barren.
You are now exploring part of Pluto's famous heart, a feature officially called Tombaugh Regio,
after the astronomer that discovered the dwarf planet, Clyde Tombaugh.
You are walking where no one else has ever walked before,
Across 990 miles or 1593 kilometres of frozen, alien ice that no longer resembles a heart shape,
but instead a vast, desolate region billions of miles away from home.
You are located on the upper edge of the hearts western lobe, a young, crater-less plain called
Sputnik Planitia, that is surrounded by towering, pinkish coloured, rock hard, water ice mountains.
The ice you are standing on, however, is not water ice, but instead, frozen nitrogen
that is slowly shifting and moving below your feet, like a glacier back on Earth.
Scientists think that Sputnik Planitia formed when a large object slammed into Pluto,
creating an enormous impact basin that slowly filled with volatile ices, millions of years ago.
As you have already noticed, the gravity on Pluto is extremely weak, here the average person only
weighs about as much as a newborn baby on Earth, and so rather than walking, you are
actually hopping across this bizarre landscape. Although you are wearing your protective super
science fiction space suit, you may also be able to hear the gentle sound of wind
circulating around you, a natural phenomenon that is likely caused by the nitrogen ice you
are standing on melting during the day and turning into vapour, but then freezing during the night
and falling to the surface. It's almost like Pluto's heart, is slowly beating.
Looking above this frozen landscape, Pluto's largest moon, Charon might just be visible
looming over the horizon. It never rises nor sets,
instead just hovers over the same spot, only ever showing the same face. A phenomenon called
tidal locking. Unfortunately for us, however, Sputnik Planitia is located almost on the opposite
side to where Charon can be fully observed. But you can still see part of its complicated,
cracked and cratered surface. Evidence that the frozen, static moon has been battered in the past.
Scattered across this smooth, frozen ocean of nitrogen, enormous chunks of water ice can also
be seen, As these aerial images reveal. The blocks are likely fragments of larger
formations that have broken apart, but what is strange about them is that they
are slowly floating across the surface. They are drifting along this smooth plane by a
mysterious process that is happening below your feet, deep within Sputnik Planitia.
The strange textures and deep crevasses that separate this region suggest that underneath
the thick layer of nitrogen ice, convection is occurring, which happens when fluid is
warmed unevenly. Meaning that something within Pluto is warmer than the surface,
causing this gigantic sea of frozen nitrogen to slowly shift
and move, possibly even creating a subsurface slushy liquid ocean.
On average Pluto is around 3.7 billion miles away from the sun,
which is 5.9 billion kilometres away, the star that allows life to flourish across our planet,
now looks like a small point in a dark, pinpricked sky. But even at this extreme distance,
it is still fairly bright, around 300 times as bright as a full moon back on Earth.
The comfort and protection of our beautiful blue home is almost a decade away,
towards that shining star. A journey that has been made by only one robotic spacecraft and now you.
So Where shall we explore next? You decide - shall we visit the most volcanically
active world in the solar system, Io, Jupiters third-largest moon........or perhaps the liquid
methane lakes of Titan, Saturn's smog covered moon. Let me know in the comment section below.
Thank you for watching, I hope you enjoyed your journey across Pluto' frozen heart
and I'll see you next time