MSL Curiosity #11: Building Curiosity: Mars Rover Power

Building Curiosity: Mars Rover Power - October 19, 2011

Curiosity is the biggest robot explorer ever to rove Mars. How do you power something like that?

Transcript
Building Curiosity: Rover Power!
Hi I'm Ashwin Vasavada the Deputy Project Scientist for the Mars Science Laboratory mission and its
Curiosity rover. So a lot of people wonder why Curiosity doesn't have solar panels like the Mars
Exploration Rovers, Spirit and Opportunity. The Mars Exploration Rovers often found themselves short
on power as dust settled on their solar panels. This was especially a problem in the short days of winter.
We need a good strong and reliable source of power to keep Curiosity going for over two years on Mars.
Curiosity is two times bigger, five times heavier and has fifteen times the weight of scientific equipment
relative to Spirit and Opportunity. Like those Rovers, Curiosity surveys the landscape and examines
rocks up close.
Curiosity's scientific mission involves driving around this landing site, perhaps up to fifteen or twenty
miles collecting samples of rocks and soils with a big jack hammer drill located on the end of a six foot
robotic arm. Those samples are delivered to the rover and analyze with some very sophisticated and
power hungry analytical laboratory instruments. That's where the MMRTG comes in. The Multi‐Mission
Radioisotope Thermoelectric Generator is a power source that we've used for years to power up
spacecraft that have gone to the outer planets and even the Apollo missions used it on the moon.
Behind me you can see a full scale model of Curiosity, including the generator in the back. On this half
scale model of the generator you can see what's inside. The generator contains a specially produced
form of plutonium dioxide. The natural decay of this radio isotope gives off heat which these
thermocouples can turn into electricity.
The generator provides both electrical power and heat to the rover. About 100 watts of electrical power
is used to continuously charge the rover's battery. Also, heat can be pumped off of the generator using
pipes to keep the rover's insides warm including the scientific instruments.
With Curiosity's generator, there's a guaranteed way of charging the battery year around in all sorts of
conditions. Curiosity's generator was developed by the Department of Energy and will be installed on
the rover just a few days before launch. But to make sure everything works together properly the
engineers installed the actual generator on the rover for the first time. The blue light that you see was
just additional lighting to help them make sure they could see what they were doing.
The Curiosity rover and the spacecraft that will take it to Mars are currently in Florida undergoing its
final preparations for launch. Everything's going well and all of us on the science team can't wait for its
launch later this year and its arrival to Mars next summer.
I'm Ashwin Vasavada and this has been your Building Curiosity update.

Category:

Science & Technology

Tags:

• Mars Science Laboratory
• NASA
• JPL
• Curiosity
• Jet Propulsion Laboratory
• mars
• atomic
• power
• nuclear
• engine
• Space

[Huantans]

once this toy is on Mars safely, it will go on for years and years with this type of MMRTG

[Eddie42023]

@FatManDoubleZero RTG's last for decades. While this particular design is new, it's the same process used to generate electricity for the Pioneer, Voyager, and more recent missions. The other batteries on Curiosity are rechargeable and they will probably last more than two years (and several hundred charging cycles) as well.

[FatManDoubleZero]

Seems to me that a power source that lasts longer than 2 earth years would be the more prudent choice for a robot that costs 2.5 billion tax payer dollars.