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From its incredible launch on the 5th May 2018,
to the present day as it reached its ultimate
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powering down, Insight has been an incredible
lander. It has peeled back the surface of Mars,
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and listened to the planet’s slow heartbeat
to gain knowledge unseen by any mission that
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has gone on before it. It has faced adversity;
from day one, Mars fought back with an unending
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assault to wear it down, or catch it off guard.
But ultimately, its contributions to our planetary
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understanding are irrefutable. And it did so
with a surprising tool – the planet’s quakes.
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I’m Alex McColgan, and you’re watching
Astrum. Come with me and discover
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how Insight did what it did, as well as
exactly what it learned. In this supercut,
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we will explore the mission
of Insight, as it happened.
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In the early hours of the morning of the 5th of
May, 2018, at Vandenberg Air Force Base, Space
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Launch Complex 3-E in California, NASA scientists
waited in nervous anticipation at their computers.
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Outside in the darkness stood an Atlas V rocket,
a nearly 60m tall, 2-stage behemoth capable of
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lifting nearly 9000kg into geostationary orbit.
Atlas V rockets like this one have launched dozens
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of times, but it’s impossible not to feel a
degree of nervousness with each new attempt.
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Last time this launch was scheduled, it had to
be pushed by several months because of a vacuum
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leak involving the SEIS instruments in its
cargo. Over half the missions to Mars to this
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date had either never left the ground, or failed
once they arrived on Mars. Even at this stage,
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there is always a chance of something going
wrong. This Atlas V was here to carry Insight;
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a lander tasked with uncovering Mars’ inner
structure by studying seismic vibrations.
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It was not the first lander to attempt this,
but it hoped to be the first one to succeed.
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NASA had sent two prior missions to Mars
with Seismometers; Viking 1 and Viking 2.
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However, Viking 1’s seismometer malfunctioned on
landing and could not deploy, and while Viking
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2’s seismometer did manage to get readings, there
was no way of telling whether what it read was a
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seismic vibration, or just the wind. This degree
of uncertainty made its readings less reliable.
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With Insight, NASA would attempt to close
this potential source of error. The signal
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came. The scientists received their last weather
reports. Launching a rocket is a risky business.
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Wind-speed, cloud coverage, even solar weather
can negatively influence a launch. All must be
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accounted for. But here, they were given the green
light. Insight would be launched within the hour.
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Insight is a metre-high, 6m-long
lander sporting two large solar panels,
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in a similar design to the Phoenix lander. It
comes equipped with multiple instruments for
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scientific research. It carries a seismometer
with a windshield, and a robotic arm that
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will place the sensitive instrument onto
the flat surface of the Martian planet.
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With this it will detect the vibrations
caused by quakes in the Martian mantle,
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or by meteor impacts. Through careful evaluation
of the time delay between the various kinds of
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seismic waves from a single event, it will be
possible for scientists to piece together Mars’
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inner structure with a greater degree of certainty
than ever before. But that is not all. Attached is
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a suite of weather-sensing equipment, to eliminate
any debate as to the source of the vibrations it
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was detecting, not to mention helping scientists
to better understand the climate on Mars.
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And to give it an even greater understanding of
the state of Mars beneath its surface, it carries
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a “Mole” – a hammer-powered digging tool intended
to burrow deep down into the Martian soil and take
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temperature readings. A large drill would not be
economical to carry, so this was thought to be
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a more efficient design. The better we understand
the structure of Mars, the more we can learn about
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its formation. And with it, the formation of other
rocky planets in our solar system - like our own.
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With InSight, we hope to learn if Earth
is an anomaly in the Solar system.
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Are many of the other planets like us?
What does this say about our formation?
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And so, at around 4 o clock in the morning,
Insight launched for Mars. Causing bone-crushing
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g-forces, the first stage of the rocket burned for
just 253 seconds before its fuel was expended and
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it detached. Then the second stage – Centaur –
kicked in. This burned for another 14 minutes,
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which was enough time to reach escape velocity.
Insight had been built to resist the strain. This
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first stage was a success, but now it would be
time for the long trip through space. It would
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take another 6 ½ months to travel across the 484
million km between Earth and Mars. These months
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would be quiet, serene, and cold, as it drifts
through the star-studded vastness of space.
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Insight’s arrival on Mars would be quite
the opposite experience. It would be fast,
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hectic, and hot. Insight entered the
atmosphere 125km up at almost 20,000kmph.
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This entry generated a lot of heat, roughly 1500c.
Fortunately, Insight’s final stage came with heat
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shields which were able to absorb this blistering
fury. And once the lander slowed down enough,
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the heatshields popped off and a supersonic
parachute deployed, further slowing InSight
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down. Yes, Mars does have an atmosphere, although
it is very thin compared to Earth’s standards.
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With the speed InSight was travelling though,
this parachute still made a big difference,
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although it wouldn’t be enough by itself to
stop the lander from smashing into the planet.
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But fortunately, Insight had planned for this.
Unlike the Mars rovers which just had giant
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airbags to bounce on landing, this spacecraft
came equipped with its own rockets to land.
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So, InSight’s legs sprang into
position, ready for landing.
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Once the parachute slowed it down enough, that
too popped off, leaving just the lander itself.
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It then used its onboard rockets to carefully
reach the surface. This whole process took place
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over the course of about 7 minutes. It touched
down successfully on the 26th November 2018.
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Upon impact with the surface, the rockets kicked
up a lot of dust. This is not very good for
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solar panels. So, InSight waited 16 mins before
deploying its solar array to let the dust settle.
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This impressive unfurling can be seen in this
testing environment before it launched. On Mars,
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these panels generate around 300-600 watts under
normal conditions. However, dust in the atmosphere
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does affect power generation, as clouds would
on Earth, so this can be different every day.
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Let’s pause now, and take a look around.
The view that greeted InSight seems bleak
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and inhospitable, but it would need to
get used to it – this rock-strewn, flat,
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dusty terrain would be its home
for at least the next two years.
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Now, Insight was intended to be a 2-year mission.
Unlike rovers, it had no tools for moving itself
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around. But that would not be necessary to
fulfil its purpose. Its mission was to sit,
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listen, and learn. It had a lot of work to
do. Insight’s mission to Mars had begun.
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Far above the thin Martian atmosphere,
a strange new sight had arrived.
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Two little lights twinkled in the night sky. These
were not new stars; they were cube sats, called
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Marco A and B, and they had been following Insight
for the last several months. Their mission was to
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relay real-time information back to Earth about
whether the landing had been successful or not,
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and if the solar cells had deployed. The Marco
mission was a technology demonstration mission,
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so it didn’t have scientific instruments, but
rather it carried different technologies to test.
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These satellites were really small, only the size
of a briefcase. They were the first time cubesats
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have been sent into deep space, and at the time,
no-one was sure how well they would do. But so
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far, they had performed exactly as hoped for. The
Marcos began listening out for UHF frequencies
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from InSight with the antenna on the bottom
of the spacecraft, ready to transmit that data
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back to Earth using this bigger antenna. The big
antenna operates like a satellite dish on Earth,
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except they designed it to be flat so it can be
space efficient. Amazingly, these satellites only
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generate 17 watts of power, yet are still able
to receive signals from the surface of Mars and
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transmit millions of kilometres back to Earth. Of
course, NASA was not going to put all their eggs
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in one untested basket. If Marco A and B hadn’t
worked, Insight would also be able to communicate
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with some of the other orbits already around Mars,
like the Mars Reconnaissance Orbiter. The only
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difference is that the MRO can’t relay information
back in real-time. These lights would not be in
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the sky for long, though. After performing their
mission, the Marco cubesats would fly by Mars,
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unable to slow down enough to enter orbit, and
instead go on to forever drift around the Sun.
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But that is not what Insight sees. Insight does
not know the fate of the machines that broadcast
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its messages. All it knows is that it’s time to
open its eyes… and maybe call to mission control
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to let them know it arrived at its destination OK.
The first thing InSight did was send back signals
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to Earth that it has touched down safely. Along
with that signal comes its first famous image.
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This first image is a little messy. As previously
mentioned, a lot of dust had been kicked up by
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the landing, as InSight used descent rockets to
slow its fall. Fortunately, Insight’s team knew
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this would happen and attached a transparent
lens over Insight’s camera to protect it.
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Later, Insight would remove this lens, to take
clearer pictures for the rest of the mission.
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Meanwhile, another camera pointing under the
lander revealed the effects of the rockets,
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which had carved out mini craters under the craft.
InSight deployed its two circular solar panels,
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now that it could collect sunlight
without dust reducing its efficiency.
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From then on, it was time to work. InSight quickly
began collecting data, even before deploying any
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of its science instruments. The first thing
it recorded was the Martian wind, picking
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up vibrations sensed by the seismometer still on
the lander. This is what it sounds like, although
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I should note that you will probably either
need a subwoofer or headphones to hear this.
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This has not been sped up, these literally
are the vibrations caused by Martian wind
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going over the solar panels of the lander, the
frequency of the vibrations converted to audio.
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For the benefit of those who can’t hear
it, here is it pitched up two octaves.
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InSight can also detect changes in air pressure.
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Here is the air pressure changing
as the wind blows across the lander.
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This audio has been sped up by a factor of
100 for it to be within human hearing range.
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What is fascinating is that we don’t have
to just imagine the wind passing by InSight,
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as it was also able to capture footage
of water ice clouds passing by overhead,
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visibly showing the direction of the wind. Yes,
although Mars is currently a barren wasteland,
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there is still a tiny amount of
water vapour in the atmosphere.
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Now limbered up, its warm-up science done,
Insight was ready for the main event.
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One of its primary missions on Mars was to listen
out for seismic activity. But its seismometer
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(SEIS) was still strapped down on Insight’s body.
It would need to use its robotic arm to lift its
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SEIS instrument and place it directly onto the
Martian soil. But not just anywhere would do.
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If it was going to settle in for a long two
years of listening, Insight wanted to choose
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the best patch of ground. Something flat, with
no rocks in the way, so its windshield could lie
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flush with the ground and provide a perfect sound
barrier, providing a means for SEIS to collect its
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data uninterrupted. And it had a team to help it.
Almost immediately after landing, InSight started
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taking 3D images of its surrounding area in order
to find the perfect spot to place the seismometer.
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Based on those 3D images, NASA actually recreated
this area as accurately as possible back on Earth,
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even going as far as using the Hololens
augmented reality headset to match up the
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surface of Mars with the environment they were
recreating. Once the perfect site was chosen,
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the go-ahead was given, and InSight carefully
used its robotic arm to place the seismometer
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on the surface of the planet. From there, it
began detecting Mars’ faintest vibrations.
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Then it was time for the mole. And it
was here that things started to go wrong.
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Insight’s Mole was a piton-shaped self-digging
tool designed to dig up to 5m down into the
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Martian soil, taking temperature readings every
10cm, and then extrapolating these readings to
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estimate the thickness of the Martian crust. A
drill that could go this deep would have been
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too large and unwieldy to bring to Mars. The
Mole’s internal hammer would get around this
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problem. By hammering itself gently into the
soil, and having the dust of Mars fall into the
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hole it was forming to provide it with friction,
Insight’s mole could in theory reach the 5m depth.
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Insight’s mole had been tested in conditions
recreated to be as similar to Mars’ dusty surface
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as possible. Only, on Mars itself, it wouldn’t
dig. Unfortunately, the mole only got 30cm
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into the dry soil of mars before getting stuck.
Scientists back on Earth scratched their heads.
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Had it hit a very hard rock? Or was the soil
simply not providing enough friction? Either way,
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the mole was now stuck – titled at an angle
before it had even fully exited its housing.
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Earth-based teams attempted to replicate the
problem and look for a safe way to pick up the
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housing around the mole, and maybe use the
robotic arm to straighten its course. They
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had to be careful not to damage it, though, as the
robotic arm had not been designed for such a task.
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After many weeks of deliberation, they
split the task, and started removing the
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housing to better see what they were doing.
Carefully, they coaxed off the outer housing.
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But it would be some time before
further progress could be made.
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If friction was the problem, scientists were
considering trying to use the robotic arm to push
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down on the soil right next to the mole, hopefully
giving it the friction it needed to start
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digging deeper. It would take careful planning
before this method could be attempted, though.
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It was July 2019 when the housing was removed – 8
months after Insight’s arrival on the planet. It
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would be another 3 months before their next move
was enacted. Meanwhile, though, things weren’t
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all bad. Back in April, Insight had detected its
first Martian quake. This is what it sounded like.
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Again, the vibrations have been
sped up by a factor of 60 as the
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frequency would not be audible to the human ear.
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While data like this doesn’t need to be
converted to audio for scientists to use it,
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it is useful for us laypeople
so we can better grasp the data.
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What you will notice though is
how sensitive this seismometer is.
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Even under the windshield, it can still
pick up vibrations caused by the wind,
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and even the robotic arm moving can be easily
detected even though it’s a few meters away.
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Detecting seismic activity is not all InSight can
do. InSight was acting a little like a weather
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station on Mars, with instruments detecting wind,
air pressure, and air temperature. As you can see,
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even at the equator Mars is a chilly -25c at its
warmest at the moment, bottoming out at -100c.
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These low temperatures are a threat to any
mechanical Martian mission. The fluctuations
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into freezing cold can cause weathering on
scientific equipment that can quickly break them.
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If it weren’t for onboard heaters powered by
InSight’s solar panels, InSight would have
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already been in big trouble. Insight was also
able to detect some gusts of up to 60kph and
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low air pressures, about 6mbar compared to Earth’s
1bar. With its first readings taken, but also with
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its first obstacles encountered, Insight’s mission
was underway to mixed fanfare. Let us jump forward
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now in time. Months have ticked by. InSight
now approached its first year mark on Mars.
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Scientists had been considering the problem of
Insight’s Mole. By this point, they began to
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be more certain that it was not an underground
rock that had stopped the Mole in its tracks.
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Scientists had chosen this landing site especially
because there were few large rocks in the area,
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and the mole had been designed in such a way that
it should have been able to go around small rocks.
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The team had taken their time to think through
what might be causing the problem, doing their
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best to create a replica of the situation
on Earth using data from Insight’s cameras.
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This isn’t a perfect process, as it’s impossible
to perfectly mimic the lower gravitational
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conditions of Mars on Earth even with replicas
made from scaled-down lighter materials,
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but by October 2019 they had figured out that
the likely problem was indeed a lack of friction.
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When taking photos of the soil around the
now-exposed mole, they saw that the soil
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in this spot was different from what they’d
been expecting. Although the surface you see
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here certainly appears loose and dusty – ideal for
hammer-based digging – only a few inches deeper,
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there appeared to be a layer of cemented soil
known as duricrust. The particles of duricrust
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stick together more tightly, which means they
won’t fall into the hole the mole is creating, and
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thus weren’t providing the friction necessary to
dig deeper. Scientists hadn’t realised that this
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type of soil was here when they picked the site
for landing, as it had been hidden beneath the
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surface. But what to do about it? While Insight
was equipped with a robotic arm, the top of the
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mole was not designed to be grabbed by this arm,
so they couldn’t just move it to another position.
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And as you can see here, there is a delicate
cable designed to relay data from the mole back
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to Insight, which could be damaged if they just
push down on the top of the mole with the arm.
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So, their first plan was to place
the arm next to the digging mole,
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pinning the mole in place. Perhaps this would
provide the friction necessary to get it started.
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Unfortunately, this proved to be not enough. The
Mole floundered in the dust, making no progress.
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Next, the team tried to scoop soil into the
hole the mole had created. This also proved
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unsuccessful. More months tick by, marking
the time between each painstaking attempt.
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Finally, in October 2020, a full year and 8
months after the mole first started trying to dig,
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scientists attempted to push the top of the
mole with the robotic arm. Although this did
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cause the mole to successfully bury itself,
the hopes that this raised were soon dashed.
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Even when completely submerged beneath the ground,
the mole would not go any deeper on its own.
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By 14th of January, 2021, the team
gave up on the mole altogether,
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although they still felt that they’d learned
valuable information for future missions about
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the nature of Martian soils. I think they’ll
have a new respect for duricrust going forward.
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Fortunately, Insight’s other scientific equipment
had been working much more effectively during this
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time. SEIS, the seismometer, was doing a much
better job of providing a glimpse into Mars’s
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inner workings. SEIS had been listening to the
sounds of Mars for over two years by this point,
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and had detected over 500 different seismic
events. Mars does not have tectonic plates
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like Earth does, but it does have volcanic regions
that produce quakes from time to time. And quakes
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produce different types of vibrations, such
as P-waves and S-waves, that travel through
00:22:25
the mantle at different rates. By timing the
difference between when these waves arrive, and
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listening out for their echoes as the vibrations
bounce off the inner layers of Mars, it becomes
00:22:36
possible to work out Mars’ internal structure,
as well as learn other fascinating insights.
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Scientists by this point had learned 3
interesting things from all this data.
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First, Mars tends to have frequent, but small,
quakes; none more powerful than magnitude 3.7.
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Scientists were surprised that they’d detected
nothing more powerful given how frequently
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smaller quakes were happening. Perhaps Mars was
more static than was expected? Or perhaps they
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simply haven’t been lucky enough to witness a
big one? It was too early to tell for certain.
00:23:11
Second, the wind hides quakes. Because SEIS is so
sensitive, even with its windshield it could hear
00:23:18
the vibrations caused by the wind, and sometimes
this masked the vibrations of small quakes,
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like static on a radio. During the windier parts
of Mars’ yearly cycle, the number of quakes
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appeared to go down, but this was likely
just because SEIS wasn’t detecting them.
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To counter this interference, scientists
formulated a plan to bury parts of the
00:23:38
seismometer using the robotic arm scoop, as this
might reduce the interference from the wind.
00:23:44
Finally, and strangely, Martian quakes do not have
surface waves. All quakes create waves. Two of
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the main types – Primary waves and Secondary
waves – travel through the mantle. However,
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normally there are also “surface waves” that
run along the surface of the planet crust, and
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for some reason these were not being detected on
Mars. Scientists are still not quite sure why, but
00:24:10
wonder if this is evidence of extensive fracturing
of the upper 10 kilometres of Mars’ crust, which
00:24:15
might be diffusing the waves. To find out more, it
would be necessary to wait and collect more data.
00:24:22
However, this is more difficult than it sounds.
After two years, time was no longer on Insight’s
00:24:28
side. Insight had reached the end of its expected
mission duration, and amazingly was internally
00:24:35
still going strong. However, an external
problem had arisen. Dust. Little by little,
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fleck by fleck, dust had built up on Insight’s two
solar panels – the two solar panels that provided
00:24:48
life-preserving power to its onboard heaters.
Insight had no machinery to clean its own solar
00:24:54
panels. Scientists had hoped that dust devils
would blow away this dust in “cleaning events”,
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but although some dust devils had been detected,
so far – by bad luck – none had passed over
00:25:06
Insight. By February 2021, Insight was now only
collecting 27% of its potential power intake.
00:25:15
Choked of energy-giving sunlight, Insight was
beginning to feel its age. Its spirit was willing,
00:25:21
but its power-reserves were weak. Faced with
this, scientists had to navigate a delicate
00:25:27
juggling act. They needed to decide where to send
Insight’s dwindling power reserves – to the arm,
00:25:33
to the SEIS reader, the radio, or the
vital heaters that keep Insight alive.
00:25:40
And by February, Mars was entering its winter
period, as well as “aphelion” – the time in
00:25:46
Mars’ year when it’s furthest from the sun, and
the furthest from that precious source of power.
00:25:51
There was only one thing they could decide.
They had to settle Insight down to hibernate,
00:25:57
using its power mostly to keep its circuitry
safe and warm. They hoped that come July,
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as Mars gets closer to the Sun again, Insight
could bring its other equipment back online.
00:26:07
Hopefully, a cleaning event would come
along, and the science could continue.
00:26:13
Spring arrived. Insight awakened from its
hibernation. But as it powered up its scientific
00:26:19
systems, it still felt weak. The dust on its solar
panels remained, and was only getting thicker.
00:26:26
Insight was faced with its own mortality – the
growing realisation that it never would get
00:26:30
better, or be at its prime again. But in spite
of its diminishing power, NASA had been so
00:26:37
impressed with Insight’s data collection that they
extended Insight’s mission for another two years.
00:26:42
Insight rose to the task. With limited time left
to it, and the end nearing, it threw itself into
00:26:49
its task. Up until this point, no quake larger
than a 3.7 mag had been detected. If Insight
00:26:56
could find something like that, it would be the
crowning jewel in the data it had collected.
00:27:02
But it wouldn’t be easy lasting long
enough. At the start of the mission,
00:27:06
Insight’s panels were capable of producing
5000 watt-hours each Martian day. Now,
00:27:12
they were only producing 500 watt-hours – about
enough to power an electric oven for 10 minutes.
00:27:18
It was now a race against time to find that last
big quake, before Insight powered down forever.
00:27:26
Back on Earth, its team had its back. Scientists
were keen to buy Insight that little more time
00:27:32
that it needed to hopefully find that quake. And
in early June 2021, they struck upon a seemingly
00:27:39
crazy idea. How could you remove dust from solar
panels, when you only had a large, clunky robotic
00:27:46
arm with a scoop? Counterintuitively, add
more dust! Specifically, to slowly trickle
00:27:53
sand down onto the panels using Insight’s
scoop while the Martian winds were blowing.
00:27:58
Hopefully by doing this, the wind would alter the
trajectory of the sand so it would bounce off the
00:28:04
panels’ edges, but as it hit the panel it would
knock dust loose, thus removing it in the process.
00:28:10
This plan might sound crazy in theory, but
incredibly, in practice, it worked! Although
00:28:17
it wasn’t much, by doing this Insight gained
an additional 30 watt-hours of energy a day.
00:28:23
This boost in power provided Insight with an
extension of life. Insight made it through the
00:28:29
Summer of 2021 and into the following year, which
turned out to be a game-changer. In the final
00:28:35
year of Insight’s life, past the point where it
should have died, it detected its largest quakes.
00:28:42
In May 2022 the ground rumbled. Data streamed
in. Insight’s SEIS sensor detected a Mag 5 quake.
00:28:51
Mars’ lack of plate tectonics makes this
a true giant of a quake for the planet.
00:28:57
Just a few months later, Insight’s end neared.
In November 2022, NASA scientists start to pack
00:29:05
down their side of the project. With
the data that Insight has collected,
00:29:09
they start collating it into a package that will
be accessible to researchers around the world.
00:29:14
They packed up the Earth-based replicas of Insight
and the Martian terrain that they’d been using.
00:29:19
They prepared to announce to the world that
Insight is in its last couple of weeks of life.
00:29:26
But Insight’s legacy is not in the metal of its
form, sitting forever on the Martian landscape.
00:29:31
It is in the things that it learned, the knowledge
it brought us. So, for one final time: what did we
00:29:38
learn? To begin with, thanks to Insight’s data,
we now know that Mars does indeed have a crust,
00:29:45
a mantle and a core, just like on Earth. However,
that crust is much thinner than we expected. It
00:29:52
contains 2 to 3 sublayers and descends 20-37km
deep, compared to the Earth’s which can have a
00:29:59
thickness of 70km. Its mantle is not as hot as
scientists previously believed and descends a
00:30:06
further 1,560km. Finally, its core is larger than
scientists thought, with a radius of 1,830km.
00:30:17
Surprisingly, it is also less dense
than expected. This has led scientists
00:30:22
to predict that it is not simply made of
Nickel and Iron, like the Earth’s core,
00:30:26
but that it must contain lighter elements
like Carbon, Oxygen, Sulphur and Hydrogen.
00:30:32
This is a fascinating insight. It explains
why the core of Mars is still molten.
00:30:38
Much like salt’s ability to reduce the freezing
point of ice – which is why you see grit
00:30:43
thrown on roads in cold weather – these lighter
elements reduce the freezing point of Mars’ core.
00:30:50
It also points to the origin of the planet. These
light elements must have been collected into Mars
00:30:55
in the very earliest periods of the solar
system’s history, as by the time Earth was
00:31:00
formed these elements were not around in as great
a quantity, explaining why Mars’ core has them and
00:31:06
ours doesn’t. They were also found further out,
indicating that Mars may have been brought closer
00:31:12
into the Sun’s gravity as time progressed, before
finding the stable orbit it navigates along today.
00:31:18
It confirms that during the early formation of
Mars, all the cosmic dust that came together must
00:31:24
have heated up and become molten, thus allowing
the heavier core metals to easily sink to the
00:31:30
planet’s centre. During this period, or soon after
it, Mars began to experience its dynamo effect.
00:31:38
Mars today has only a weak magnetic field compared
to Earth’s. Most of this field is left over as
00:31:44
residual traces of magnetism, locked into many of
Mars’ surface rocks. However, back in its early
00:31:51
formation 4 billion years ago, Mars’ moving
metals in its core created a massive dynamo,
00:31:57
imbuing these rocks with their magnetism. When
the planet cooled, hot materials were not able to
00:32:03
move about as quickly as they needed to keep the
dynamo going. In time, Mars’ dynamo ceased to be.
00:32:11
Thanks to the data provided by Insight,
scientists will have a much better idea
00:32:15
of the timescales involved in this dynamo.
This is relevant because when we talk about
00:32:20
magnetic fields and dynamos, those can
affect what the atmosphere was like.
00:32:25
And once we understand that, we will have a
clearer picture of Mars’ early habitability.
00:32:31
Insight might give us an idea of the time period
when life was most likely to form on Mars.
00:32:38
Insight has given us an incredible amount of
raw data, including a fascinating comprehension
00:32:43
of Martian weather patterns. Yet, there are
still many mysteries. Even though we now know
00:32:50
the rough dimensions of Mars’ inner structure,
Insight’s findings have actually disproved some
00:32:55
previously existing theories. For instance,
under a particularly volcanic region on Mars’
00:33:01
surface known as Tharsis – home of Olympus
Mons, a volcano two and a half times as tall
00:33:07
as Mt. Everest – there exists a hotspot of magma
that feeds the volcanic processes we see in this
00:33:13
region. Due to the absence of plate tectonics, it
was unclear what exactly was causing this hotspot,
00:33:19
which seemed to have been present, unmoving,
for billions of years of Mars’ history.
00:33:25
Scientists originally thought that this
hotspot was being fed by a lower mantle,
00:33:29
but it turns out that Mars does not have a lower
mantle. As such, it is back to the drawing board
00:33:34
to explain what is causing this phenomenon.
Still, these are the sorts of questions and
00:33:40
discoveries that drive scientific endeavour.
And the discoveries that Insight has given us
00:33:45
will inform future missions for decades to come.
Scientists will pour over the data, analysing P
00:33:52
waves and S waves, attempting to find patterns
and meaning in the sounds of Mars’ rumbling
00:33:57
heartbeat. And who knows how much more we will
discover as a result of this successful mission!
00:34:04
If more comes in, I will keep you posted.
But now that Insight has powered down,
00:34:09
as it closed its eyes on the scattered clouds
and dusty plains of Mars, I hope that it can
00:34:15
rest easy. In spite of its challenges, and the
ups and downs, it did what it came there to do.
00:34:26
A quick shoutout for my new Displate
collections on planets. I put a lot of
00:34:31
work into these and think they look amazing.
If you want your favourite planet on your
00:34:35
wall plus a discount on everything on
the website, check the links below.
00:34:41
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00:34:47
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All the best, and see you next time.
