Curiosity launch — Mars rover
On 26 November 2011 the Mars rover Curiosity, weighing about 900 kg, was launched. After landing by ‘sky crane’, it is still climbing Mount Sharp inside Gale Crater today.
Available views: Orbit ✓ · Sky — (not visible in the sky)
The story
On 26 November 2011 Curiosity left for Mars on an Atlas V rocket. The rover weighed about 900 kg, roughly five times as much as the earlier rovers Spirit and Opportunity. That was too heavy for the old method of wrapping the rover in giant airbags and letting it bounce to a stop on the ground.
The engineers' answer was the ‘sky crane’. A rocket-powered platform hovers above the Martian ground and slowly lowers the rover on cables. When the rover's wheels touch the surface, the cables are cut and the platform flies off to crash at a safe distance. The method had never been used on Mars before.
After a cruise of about eight and a half months, Curiosity landed on 6 August 2012. Getting from the top of the atmosphere to the ground took about seven minutes, but a signal from Mars needed about 14 minutes to reach Earth. So the team on Earth could do nothing during the landing, and those minutes became known as the ‘seven minutes of terror’.
The landing worked. Curiosity came down on the floor of Gale Crater, less than 2.4 km from its target. Since then it has found signs of an ancient lake and, by September 2026, had driven more than 36 km as it climbs Mount Sharp. The same landing method was used again for the Perseverance rover in 2021.
Mission goals
Curiosity widened the question from ‘Was there water on Mars?’ to ‘Could Mars have supported life?’ A year after landing it drilled into rock at a place called Yellowknife Bay. The results showed that long ago a lake of water that was neither salty nor acidic had stood there. Scientists judged that tiny microbes could have lived in such a place.
The rover also found organic molecules, which contain carbon, inside the rocks. Organic molecules are building blocks of life, but they can also form without life. So Curiosity did not find life. What it did provide was the first strong evidence that ancient Mars may have been a suitable home for it.
Curiosity has also gathered data for the day people travel to Mars. An instrument on the rover measured how much space radiation reaches the Martian surface. The dose is about 0.64 mSv a day, or roughly 230 mSv a year. These numbers help scientists work out how much radiation astronauts would receive on a Mars mission.
Mission chronology and background
Curiosity was first meant to launch in 2009. Testing of some parts ran late, so the launch moved to the next time Earth and Mars lined up well, 26 months later. The total cost grew to about 2.5 billion dollars. The planned mission was about two years long, but in December 2012 it was extended with no end date.
Years of driving have brought some damage. From 2013, holes and cracks began to appear in its aluminium wheels, so the team now picks routes that avoid sharp rocks. In December 2016 the rock drill stopped working, but in May 2018 engineers developed a new way of drilling and put it back into use.
Curiosity gets its electricity from the heat of decaying plutonium, not from solar panels, so dust storms that block sunlight do not stop it. Opportunity, which used solar panels, lost power and fell silent during a huge dust storm in 2018. The plutonium's output still drops a little every year, and it is now around 100 W.
Curiosity also found that the amount of methane in the Martian air rises and falls with the seasons, roughly 0.6 parts per billion in summer and 0.2 in winter. Methane can come from chemical reactions underground or from microbes, and no one yet knows which is the source here. Scientists think the answer will need Martian samples studied closely in laboratories on Earth.
Where to see it — sky and simulator
Curiosity is climbing the lower slopes of Mount Sharp inside Gale Crater, at 4.6 degrees south and 137.4 degrees east. No telescope on Earth can see the rover. Instead, the Mars Reconnaissance Orbiter, a spacecraft circling Mars, sometimes photographs the rover and its wheel tracks from above.
Mars itself is easy to see with the naked eye. Select Mars in the sky view to find its direction, its height above the horizon and its rising time from your location. Mars comes closer to Earth and brightens about every 26 months, and its next best showing, called opposition, is in February 2027.
The orbit view replay shows the flight path from the November 2011 launch to arrival at Mars in August 2012. The spacecraft starts at Earth's orbit and travels almost halfway around the Sun to reach the orbit of Mars. Following Mars in the replay shows how the launch was timed so that the spacecraft and the planet arrived at the same place at the same time.
See this for yourself — replay the moment in the orbit view
FAQ
What were the ‘seven minutes of terror’?
Entry, descent and landing took about seven minutes, but signals needed about 14 minutes to reach Earth, so the team could do nothing during that time.
Why doesn't it use solar panels?
Power from the heat of plutonium keeps it running even when dust storms block the Sun, and it gives a heavy rover a steady supply.
Did it find life?
No. It found an ancient lake where microbes could have lived and organic molecules, but not life itself.
Is it still moving?
Yes. More than 14 years after landing, it had driven over 36 km by September 2026 and is still climbing Mount Sharp.
Related
- Perseverance launch
- Viking 1 launch
- Tianwen-3 samples return
- Mars — object index
- Perseverance — object index
Times and figures are approximate — verify with official sources when planning travel. Simulation uses J2000 mean elements.