Curiosity launch — Mars rover

The one-ton rover of "seven minutes of terror" fame — still climbing through Gale crater today.

The moment of Curiosity launch — Mars rover: https://nowsky.org/e/curiosity-launch — opens at the right place and time, replayable, no login.

Available views: Orbit ✓ · Sky — (not visible in the sky)

The story

Curiosity left for Mars on an Atlas V on 26 November 2011. At 900 kg — five times the mass of the earlier rovers Spirit and Opportunity — it was too heavy for airbags, and the answer was the "sky crane", a rocket-powered platform lowering the rover on cables. It had never been flown before Mars.

On 6 August 2012, during the seven minutes of entry, descent and landing, Earth could do nothing — the signal delay was 14 minutes — hence the "seven minutes of terror". The landing was perfect, within 2.4 km of the centre of the target ellipse on the floor of Gale Crater, and the same method was reused for Perseverance in 2021.

Its power comes from a plutonium thermoelectric generator rather than solar panels, so Martian dust storms cannot stop it — the seasonal winds that killed Spirit and Opportunity are no threat. Gale Crater was chosen because the layered sediments of Mount Sharp are a bookshelf of Martian climate history: the lower layers from the age of water, the upper from the dry age, so climbing the mountain is itself time travel.

In the lake sediments it found organic molecules and evidence of a habitable environment three billion years ago, and in its fourteenth year it is still climbing Mount Sharp with more than 30 km on the odometer. Every August, on its landing anniversary, it famously plays itself a "happy birthday" tone. The orbit replay shows the eight-and-a-half-month cruise from launch to Mars.

Why it matters

Curiosity moved the question from "was there water on Mars" to "could Mars have supported life". Drill samples at Yellowknife Bay confirmed a freshwater lake of neutral pH, and organic carbon and seasonal swings in methane were detected. It did not find life, but it was the first firm answer that life could have lived there.

The success of the sky crane rewrote the standard for Mars landings. With tonne-class payloads landing precisely, Perseverance, the sample-return mission and even crewed lander designs now assume the method.

The longevity of a nuclear-powered rover is data in itself. Fourteen years of weather and radiation records feed the safety limits for human exploration, and the cosmic-ray dose it measured after landing (about 300 mSv a year) is the basis for calculating exposure on a trip to Mars.

How to watch

Curiosity sits at the foot of Mount Sharp inside Gale Crater (4.6° S, 137.4° E). No ground telescope can see it, but the Mars Reconnaissance Orbiter periodically photographs the rover and its wheel tracks from above.

Select Mars in the sky view for its altitude, bearing, rise time and apparent size from your location. Mars brightens as it approaches Earth every 26 months; the next opposition is February 2027.

The orbit replay draws the Hohmann transfer from the November 2011 launch to arrival in August 2012; following Mars shows the spacecraft on the outer track being caught by the planet. NASA's website updates the rover's position and latest images daily.

See this for yourself — replay the moment in the orbit view

Background

Originally due to launch in 2009, it slipped to the next window 26 months later because of component testing, and the cost rose to 2.5 billion dollars. Designed for one Martian year (687 days), it has now exceeded that seven times over.

Holes began appearing in the wheels in 2013, and the drill failed in 2017 before a new technique restored it in 2018. Declining generator output has shortened daily activity since 2022, but operations are expected to continue into the late 2020s.

The seasonal methane swing it measured — 0.7 ppb in summer, 0.2 in winter — is still unexplained. Whether it is geological or microbial can only be judged when samples reach Earth laboratories, and filling those sample tubes is Perseverance's job.

FAQ

What were the seven minutes of terror?

The seven minutes of entry, descent and landing during which Earth, with a 14-minute signal delay, could do nothing.

Why not solar panels?

A plutonium generator powers the 900 kg rover regardless of dust storms.

Did it find life?

No. It found a habitable environment from three billion years ago and organic molecules, but not life itself.

Is it still moving?

Yes — in its fourteenth year it is still climbing Mount Sharp with over 30 km driven, and should run into the late 2020s.

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Times and figures are approximate — verify with official sources when planning travel. Simulation uses J2000 mean elements.