Today-- well, July 14, 2015, if you're not watching
on the date-- is the last time we will ever explore a new body
that has ever been classified as a planet in our solar system.
Pluto.
Woo!
We are flying a probe by Pluto for the first time.
Up until now, Pluto has been a dot, a smear, a few pixels.
But the New Horizons probe is on its closest approach to Pluto
right now, if you're watching on the date.
As the probe has gotten closer, it's
been sending us new images from views we've never seen
before of the icy dwarf planet.
There's the whale's tail, this complex band of terrain
1,600 kilometers long, and this target in the most recent image
from July 12.
These dark and light regions tell us about Pluto's geology
and, perhaps, a frozen methane, nitrogen, or carbon monoxide
frost.
And as the probe gets closer, we will
get a clearer view of Pluto's heart
and its largest moon, Charon.
This is the view of Pluto we had before New Horizons.
And this is our view now.
This is history in the making.
The probe, which I think looks suspiciously
like a cheese head with a saucer hat,
was launched on January 19, 2006.
This voyage has taken nine years.
Nine years!
The probe, unfortunately, won't be
able to send any of those close flyby images back today.
So, when we do get them, I'll link them in the description.
So, why not?
Well, the probe is completely focused on taking data
right now.
It only gets one shot.
It's like if you see this perfect rendition of Groot,
you're going to put all your effort into getting that photo.
New Horizons will be using its power on Ralph,
the detector with visible and infrared spectrometers,
and Alice, the detector analyzing Pluto's atmosphere
and looking for atmospheres around Pluto's moons.
And the other detector is measuring the solar wind
all the way out there and the atmospheric temperature
and the space dust and more.
There's a lot of detecting to do.
And all those detectors are using less power
than a 30 watt light bulb.
How was New Horizons able to power itself that whole way?
Solar?
No.
There's not enough light from the sun
all the way out near Pluto.
In fact, the intensity of sunlight
is about 1,600 times less than that on Earth.
So, you'd only be able to put out
1 watt of power with a perfect solar panel this big.
That's not even enough power to light a single Christmas light
bulb.
Instead, the probe uses what's called
a radioisotope thermal electric generator, which
uses nuclear energy and can put out
200 watts at this point in the voyage.
So, how many probes have we sent to Pluto?
One.
This one.
This is the first one.
That's what this video is about.
And after Pluto, New Horizons will leave the solar system
after exploring some of the objects in the Kuiper Belt.
That's the doughnut-shaped region full of dwarf
planets and other small bodies.
If it were shown in pictures like this more often,
it would make the solar system look a lot less lonely.
So, is this the first time that a man-made object
will reach interstellar space?
No.
Voyager 1 launched in 1977, crossed the boundary
into interstellar space in 2013, and was the first probe
to ever do so, even though Pioneer 10 and Pioneer 11
were launched earlier.
They, along with Voyager 2 and New Horizons,
will all eventually enter interstellar space.
Which reminds me that the last time
a probe flew by a new planet was the year Taylor Swift
and I were born.
That was when we got these incredible first images
of Neptune, which were taken by Voyager 2 in 1989.
It's about time we explored Pluto, even
if it's just a dwarf planet.
We've explored all of the planets in our solar system.
And when we came upon a new one, or a new moon,
the most common reaction was that we were really
surprised by what we found.
We found auroras on Jupiter's poles, a storm on Neptune that
could swallow Earth, and explosive geysers
on Neptune's moon Triton.
The consensus among the scientists
working on this mission is that we will be surprised
by what we find on Pluto.
So, nine years of travel and we're finally there.
How did we get all that way?
Well, this was the fastest launch of any rocket
ever at 58,000 kilometers per hour.
That was more than enough to escape Earth's gravity.
Then, the probe headed over to Jupiter,
took some incredible images in 2007,
and got a gravitational boost to increase the speed
by 14,000 kilometers.
Thanks, Jupiter.
Then, the rest of the journey took eight years.
Because the solar system is freaking huge.
In the end, New Horizons travel nearly five billion kilometers
to get to Pluto.
Now, we'll probably never see New Horizons again.
But there are a few mementos on board.
Florida and Maryland State quarters,
ashes of Clyde Tombaugh, the man who discovered Pluto in 1931,
and some US flags.
But, right now, there's an opportunity
to get involved in another message being
uploaded to the probe.
If you'd like to send a digital message to the stars,
check out the One Earth project--
link in the description.
So, what's next for space exploration?
Well, we hope for more data from the probes
on the solar tidal waves that reach the probes
in interstellar space.
And NASA has upcoming plans for exploring
Europa, one of Jupiter's most awesome moons.
So, keep an eye out for all of that.
Thanks for watching.
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