>> Phoenix, out of the University of Arizona, was the first time that
NASA trusted any university to operate an entire mission except for the launch.
This project also brought a $350 million contract to my University.
Phoenix was based on a design that actually led to a failed mission that
plunged into the Martian surface.
They resuscitated the design, got all the bugs out and
did a very successful launch to the polar region.
Phoenix was not a rover.
It was a fixed platform.
But it actually watched the hydrological cycle in operation.
In fact, brining material was seen dripping down the leg of the lander.
When water has sufficient amount of salt or
other minerals, it can be liquid even at the cold Martian temperature.
It also saw a fine snow falling on one occasion,
an extraordinarily successful mission.
Our current rover on Mars, Curiosity or the Mars Science Lab, is just
beginning the heart of its mission after an adventurous and successful landing.
Curiosity steps up the size, the scale, and
the degree of difficulty of a Martian rover.
Compared to Spirit and
Opportunity, the size of go-karts, Curiosity is the size of an SUV.
Spirit and Opportunity landed on Mars in
bouncing balloon bags which were rather sensitive to problems of
the landing because they bounced to a halt protected by the balloons.
Curiosity, by contrast, used an audacious sky crane method which seemed to
have many ways that it could go wrong and yet it didn't.
Planetary scientist argued for years about where best to land on Mars.
If you have a billion dollar piece of hardware with no twin ready to go
if it fails, you better be sure when you want to land it.
In a series of conferences over three or four years,
they narrowed down from a hundred to 25 to four and finally to one landing site.
Think of it as a roulette game where you have to put all your money on one number.
The scientists chose Gale Crater because there's strong mineralogical evidence that
the Gale Crater was once a shallow seabed.
Minerals seen there are similar to the clays and silicates that are seen in
terrestrial regions of sedimentation, leading to the exciting prospect that
the Curiosity mission will be able to further give evidence of Mars' wet past.
Mars is busy enough with missions that the missions take pictures of each other.
Here's a picture of the Curiosity landing,
taken by the main Mars Orbiter at the time.
The Curiosity descent sequence was enough to give gray hairs to
all the people involved in the mission.
It was a complex sequence involving using the heat shield to
decelerate through the thin Martian atmosphere, the deployment of a parachute.
The separation of that heat shield, and then the scary part.
Lowering the rover on metal ropes and then deploying a sky crane to gently lower
it onto the surface while the spacecraft maintained an altitude of about 50 meters.
Then those cables were released and
the spacecraft flew off to crash land in the Martian surface.
There are at least six or seven places in this sequence where one mistake would have
spelled doom to the mission.
I've heard Peter Smith, the PI on the Phoenix Mission,
describe what it's like in the control room when a mission like this lands.
Essentially each group of engineer's responsible for one part of the landing
sequence is anxious and then celebrates as their part is concluded successfully.
And then all eyes pivot to the next group.
Basically, we didn't screw up, now it's your turn.
Eventually the baton is passed to last landing stage and
Curiosity landed on the surface, the softest possible landing imaginable.
[MUSIC]
>> Things are looking good.
Coming up on entry.
Vehicle reports entry interface.
[SOUND] Navigating to, field the atmosphere as we go in here.
[SOUND] Just reporting that we are seeing G's on the order of, 11 to 12 Earth G's.
[SOUND].
[MUSIC]
>> [APPLAUSE].
>> Universal two is starting.
We are now getting telemetry from Odyssey.
>> [SOUND].
[MUSIC]
>> We should have parachute deploy around Mach 1.7.
>> [SOUND].
[MUSIC]
The parachute is deployed.
[APPLAUSE] We are decelerating.
[MUSIC]
Fuselage has separated, we're on the ground.
We're down to 90 meters per second at an altitude of 6.5 kilometers descending.
[MUSIC]
Standing by for [INAUDIBLE] separation.
[SOUND] [SOUND].
>> We are in powered flight.
[APPLAUSE] [SOUND]
[MUSIC]
We're at altitude of one kilometer and descending.
[MUSIC]
[SOUND] Standing by for sky crane.
Sky Crane has started.
[SOUND].
[MUSIC]
>> Single remains strong
[MUSIC]
[SOUND].
[MUSIC]
Touch down confirmed.
We're safe on Mars.
>> [APPLAUSE]
[NOISE]
[APPLAUSE]
[NOISE] Real,
it's for real.
[CROSSTALK]
[MUSIC]