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KIDS: Our World!
EVAN: Hey Globey, you know you’re my favorite planet to explore.
There is not place more interesting than Earth.
But it’s also fun to explore other planets. So today we’re
going to talk about the challenges of exploring
Mars with the Phoenix Lander.
The Phoenix Lander is a robotic craft that NASA sent
to Mars to learn more about the surface of the red planet.
One of the coolest things about the mission was the
challenge NASA scientists and engineers had to overcome
just to get the Phoenix Lander safely to Mars.
But before we talk about all of that, let’s find out
exactly what a Lander is and what makes it so special.
A Lander is different than an orbiter...and also different
than a rover or an un-crewed Aerial Vehicle.
An orbiter is a craft that orbits around the planet to gather information.
NASA sent multiple orbiters to Mars,
such as the Mars Reconnaissance Orbiter,
the Mars Odyssey, and the Mars Global Surveyor.
These orbiters can cover vast areas of the planet since
they’re circling the entire planet. The main disadvantage
is that they’re not getting as close to the surface of Mars as a UAV or a rover.
An orbiter is very different than a rover, which is a
craft that’s designed to travel across the ground.
For example, NASA plans to send a new generation of the
rover to our Moon, so astronauts can explore the surface.
NASA also wants to send an un-crewed aerial vehicle...
or UAV for short...to Mars.
A UAV is a robotic airplane with no pilot or crew.
This UAV will be called ARES and is nicknamed the “Mars Airplane.”
The Mars Airplane will soar across the surface of Mars
and send incredible photos and video back to scientists on earth.
But the Phoenix Lander is not an orbiter or a rover or an airplane.
It’s a Lander. A Lander stays in one place after it’s
touched down on the surface. Scientists may decide to do
this if they only want to do research on that one part of the planet.
CHRIS LEWICKI: A Lander for Phoenix was important because
we really needed to have a very stable platform so that
we could dig deep into the surface of Mars and a rover
is not big enough to be able to put a big robotic arm and dig deep holes.
Also Phoenix brought with it a lot of scientific
instruments and it’s easier to take those scientific
instruments to Mars if you have a big Lander to do that with.
EVAN: Just getting the Phoenix Lander to Mars was a big challenge.
Just think about how far away the planet Mars is and how
long it would take to get there.
The Phoenix Lander reached Mars on May 25th, 2008.
The Lander had to travel 680 million kilometers from Earth.
That’s 422 million miles!
It took nine and a half months to make the journey to Mars.
Several countries have tried to send space craft to Mars
and about half the time they have failed. So when the
Phoenix Lander made it to Mars it was a
huge reason for NASA scientists and engineers to celebrate.
And think about this. NASA scientists didn’t just want
the Phoenix Lander to get to Mars. They had a very
particular place on the planet they wanted it to land...
the polar region!
CHRIS: They sent Phoenix to the polar region because it’s
a very unique area in the environment on Mars.
We knew that just below the surface of the soil were
probably formations of water ice.
And if we dug down just a little bit through that dirt
to get to that ice that’s probably been there for tens
of thousands to millions of years.
EVAN: The Phoenix Lander was launched on top a Delta Two
rocket that shot it out of Earth’s atmosphere.
CHRIS: There are so many things that could go wrong along the way.
If everything is not absolutely perfect, you’ll crash.
Lots of Math and science is required.
There are lots of calculations to be done to
figure out if things are the right size.
If they weigh the right amount, and they’re going to
have the right amount of energy or force or power.
Math is used everyday in planning these missions and
is something that everyone in the project is very skilled at.
So it’s important to learn how to do that stuff early
so you can do these exciting things.
EVAN: When the Phoenix Lander enter the Martian atmosphere,
it was flying approximately 21,000 kilometers per hour,
or approximately 13,000 miles per hour.
That is really fast.
The Lander was slowed down dramatically by using a parachute.
Then the Lander’s legs were extended.
This caused the 12 small rockets on the Phoenix Lander to fire,
which slowed the Lander down even more.
By the time the Phoenix Lander touched down on the
surface of Mars, it was traveling at only 8
kilometers per hour or around 5 miles per hour.
Scientists jokingly referred to the Phoenix Lander’s
entry, descent, and landing process as "Seven Minutes of Terror"
because it took the Lander seven minutes from the time
it entered Mars’ atmosphere at 21,000 kilometers per hour
to a full stop on the surface of Mars.
During those seven minutes, which seemed to last forever
to the scientists on Earth, NASA had no contact with the Lander.
The scientists didn’t know the Lander had touched down
safely until the Lander made it to the surface
set up it's equipment and began to send a signal to NASA.
After the Lander was safely on the surface, it stretched
out its solar panels. These solar panels collected energy
from the sun’s rays, and that energy was used to power the Phoenix Lander.
With the solar panels fully extended, the Phoenix Lander
is 5.5 meters or 18 feet long.
It weighs 350 kilograms, which is a whopping 770 pounds.
Within an hour of touching down on the surface of Mars,
the Phoenix Lander began to send communications back to
scientists on Earth.
It’s mission on Mars was just beginning, but it had already been a great success.
You can see how much math and science is involved for NASA
scientists and engineers to design the Phoenix Lander
and then successfully get it to Mars. By checking and
rechecking their math and learning from their mistakes in the past,
they were able to overcome those challenges.
And now we get to see incredible photos and video of the surface of Mars!
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KIDS: Our World!