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I don’t know what you’ve been doing with your first full week of 2019,
but the space community has been knocking it out of the park.
It’s been 11 days, and this year is already a great one for space exploration.
First, as we were all celebrating the start of the new year, NASA’s New Horizons was
zipping past the farthest object ever visited by a spacecraft.
Then, only days later, China accomplished something just as remarkable: For the first
time ever, they safely put a lander on the far side of the Moon!
Meanwhile, I had a hard time getting out of bed, multiple days in a row.
It’ll be a while before we have all of the data we’re gonna get from these two missions,
but they’re already proving that our solar system
is way more fascinating than it has any right to be.
The object New Horizons flew by is named 2014 MU69, but the mission team sometimes calls
it Ultima Thule, after the ancient Latin term for distant, unexplored lands.
And it is definitely distant.
MU69 is what planetary scientists call a Kuiper belt object, or KBO,
meaning it orbits in a region of space beyond Neptune.
The most famous Kuiper belt object is the dwarf planet Pluto,
which also happened to be New Horizons’ first target.
And while it’s turned out to be an amazing place, tiny MU69, which is only around 30
kilometers long, is probably more representative of what most KBOs are like.
So far, New Horizons has only sent back the first few pictures it snapped during the flyby,
but they’ve already revealed that this place is a weird, weird world.
Like, it looks like maybe a peanut, or a little snowman.
Between that and Pluto’s heart, New Horizons studies all the coolest looking places!
Astronomers call objects like MU69 contact binaries.
Binary because there are two objects, and contact because they’re touching.
The two parts probably formed out of the same cloud of material and then drifted together
really slowly because of their shared gravitational pull.
Today, they spin as one object, rotating about once every fifteen hours.
Scientists couldn’t figure that out before because MU69 keeps the same
pole pointing towards Earth all the time.
But now that we know what this object looks like, we have even more questions,
like what is going on with all the color variation.
Both parts of MU69 have the same reddish color, which is similar to the north pole of Pluto’s
moon Charon and seems to be pretty common for KBOs.
But the “neck” region appears to be much brighter, as do a few spots along the surface.
Of course, “bright” is relative here.
Overall, MU69 is about the brightness of nice, dark potting soil.
Even the lightest spots have just 13% reflectivity.
Regardless, mission scientists say that those bright spots seem to correspond with surface
depressions, but we will have to wait for better images to be sure.
Unfortunately, it will take a long time to get that data.
Like you might guess, there’s not exactly a 4G network at the edge of the solar system.
Download speeds are really, really slow, so it will take about twenty months to retrieve
data that was collected in just a few hours. It reminds me of the 90’s.
Mission controllers expect the very best pictures to arrive in February, but images are just
one piece of the treasure-trove New Horizons has gathered.
It took plenty of other measurements as well,
so, stay tuned for much more about the Kuiper belt this year.
Speaking of much more news, last week we told you 2019 would be a groundbreaking year for
exploring the Moon, and it already is!
On January 3rd, local time, China’s Chang’e-4 lander touched down on the far side of the Moon.
Then, just hours later, it deployed its Yutu-2 rover.
This mission is really exciting for a few reasons, but mainly,
because the Moon’s far side has long puzzled planetary scientists.
It’s covered by more craters and fewer lava flows than the parts of the Moon visible from Earth.
And because all of NASA’s Apollo missions landed on the near side,
we know dramatically less about what might be going on.
Chang’e-4 has landed in the massive South Pole-Aitken basin,
one of the solar system’s largest impact craters.
Seriously, this crater is half the size of the continental United States.
The impact that formed it may have been so violent that it excavated some of the Moon’s
inner material, called the mantle.
So if Chang’e-4 or its rover can locate any mantle material, it would help scientists
understand early lunar history, and we wouldn’t even have to dig for it.
What’s also cool about this mission is the engineering that was required to pull it off.
Landing on the far side of the Moon is especially difficult because it’s
always out of view from the Earth.
That means it’s impossible to directly communicate with anything that lands there,
a situation that’s basically unique in the solar system.
Even NASA’s Mars rovers can communicate directly with Earth in an emergency.
To stay in touch with the lander, China had to place the first-ever communication satellite
in Earth-Moon L2, a point of gravitational equilibrium just beyond the Moon.
It launched last May, and can now relay signals between Chang’e-4 and Earth.
And while it did require some extra engineering, the trade-off was worth it.
As a bonus, Chang’e-4 can also make use of this silence of the far side of the moon
to conduct radio experiments that would be impossible anywhere else in Earth orbit.
So, from the mission design to its results, this is a big moment for the Chinese space program.
With the original Yutu rover in 2013, China had already joined the U.S. and Russia as
the only nations to have operated rovers on another world.
Now, for the first time, they’re doing something no other country has done.
And that’s really great news for science.
Thanks for watching this episode of SciShow Space News!
From new missions to groundbreaking new papers, we’re here covering the latest news from
around the universe every Friday.
If you want to keep learning with us, you can go to youtube.com/scishowspace and subscribe.
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