Skip to Content
Climate change

Nuclear generator powers Curiosity Mars mission

Solar panels, used in the past Mars missions, were passed up in favor of a space battery for powering the car-size Curiosity robot.

When the Curiosity rover touched down on Mars yesterday, a specially designed nuclear generator kicked into action.

A close up of Mars Curiosity’s power source. Credit: Idaho National Laboratory.

Previous Mars missions have relied on solar panels to power the rovers, but exploration was slowed down by dust build-up on the solar panels or short winters days with little sunlight. The Curiosity Rover, which is as big as a large car, is also significantly larger and ten times heavier than previous Martian rovers.

Enter the Multi-Mission Radioisotope Thermoelectric Generator, or MMRTP, an energy source that relies on the heat generated by decaying plutonium dioxide to run Curiosity. It’s designed to run at least one Martian year, which is almost two Earth years.

The Curiosity is essentially a robotic science lab, equipped with sophisticated instruments for taking ground samples and analyzing their chemical make-up in the search for signs of life. This testing and communications equipment needs a lot of power to operate and needs to maintain a certain temperature to effectively operate on Mars where temperatures can go far below freezing.

The nuclear generator delivers both heat and 110 watts of steady electric power from an array of iridium capsules holding a ceramic form of plutonium dioxide. The heat is piped through the Curiosity carried by liquid Freon. Thermoelectric devices on the generator convert the heat into electricity with no moving parts. Idaho National Laboratory, which designed and tested the energy system, says it can operate for years.

Nuclear power has been used in 26 previous space missions over the past 50 years. The Idaho National Lab team began assembling the power source in the summer of 2008, which included tests for vibrations to simulate rocket launch conditions and making sure the generator’s electric field won’t affect on-board scientific instruments.

Deep Dive

Climate change

This CRISPR pioneer wants to capture more carbon with crops

New research at Jennifer Doudna's institute aims to create faster-growing, carbon-hungry plants using the gene-editing tool.

giant kelp underwater
giant kelp underwater

Running Tide is facing scientist departures and growing concerns over seaweed sinking for carbon removal

The venture-backed startup believes kelp could be a powerful tool to combat climate change. But some scientists fear the ecological risks on large scales.

The future of urban housing is energy-efficient refrigerators

Adapting old, energy-inefficient buildings is less sexy but far greener than many high-tech solutions.

Stay connected

Illustration by Rose WongIllustration by Rose Wong

Get the latest updates from
MIT Technology Review

Discover special offers, top stories, upcoming events, and more.

Thank you for submitting your email!

Explore more newsletters

It looks like something went wrong.

We’re having trouble saving your preferences. Try refreshing this page and updating them one more time. If you continue to get this message, reach out to us at customer-service@technologyreview.com with a list of newsletters you’d like to receive.