Following the spectacular successes of the Spirit and Opportunity rovers, expectations will be high. Both these rovers had planned mission durations of 90 sols (Martian days). When contact was finally lost with Spirit, it had been operating for over 2200 sols and had covered over 10 times the expected distance. Opportunity is still operating over 2800 sols since landing (at the time of writing). The longevity of the rovers is partly due to cleaning events, whereby Martian winds blew the solar panels clear of the dust that was expected to reduce the power output of the panels, but praise must also go to the design and engineering teams that built and operated the rovers.

Curiosity is bigger than its predecessors, having a whopping 900 kg mass (compared to 185 kg for Spirit and Opportunity). Unlike the final 'airbag assisted' landings of the earlier Rovers, Curiosity's final descent to the surface will be slowed by small rockets. The diagram shows the planned descent sequence, due to happen in August 2012. Its planned operational life is 668 sols (a Martian year – 686 Earth days).

Instruments
Curiosity carries a package of instruments to carry out 10 different investigations into the local environment.

On the mast:
•    Mastcam This is a high definition imaging system, including both a medium-angle and a telephoto lens. Overlapping portions of the images from the two lenses can be used to make 3D images.
•    Chemcam is a camera and laser system that can 'zap' a rock with a laser and carry out a spectral analysis of the resulting plasma to identify chemical elements in the rock.

On the turret at the end of the 2.1 m long robotic arm:
•    MAHLI (Mars Hand Lens Imager) A camera with a magnifying lens for taking close up images of rocks and soils, but also for wider scenes.
•    APXS (Alpha Particle X-ray Spectrometer) This emits alpha particles and X-rays, and detects any X-rays emitted by the target material. The X-ray emissions are characteristic of different elements. Unlike similar instruments on Spirit and Opportunity, the instrument on Curiosity can operate during the day as well as during the Martian night.

The arm can deliver samples to:
•    CheMin (Chemistry and Mineralogy) uses X-ray diffraction to identify minerals – the first time this kind of instrument has been used on Mars.
•    SAM (Sample Analysis at Mars) is a mini-laboratory that assesses soil, powdered rock and atmospheric samples for carbon compounds and other compounds important to life. The tools include a mass spectrometer, a tunable laser spectrometer and a gas chromatograph.

The REMS (Rover Environmental Monitoring Station) is basically a weather station, and will take measurements of wind speed and direction, air pressure and temperature, relative humidity, ground temperature, and UV radiation.

The RAD (Radiation Assessment Detector) will monitor particulate radiation. This is the only part of the mission that is also aimed at informing the design of future crewed missions to Mars, in particular the radiation shielding necessary.

The DAN (Dynamic Albedo of Neutrinos) investigation will look for water bound into minerals beneath the surface.

The MARDI (Mars Descent Imager) will film the final stages of Curiosity's descent to provide detailed images of the area to be explored. The video will be made available on-line, so one to watch out for!

Various instruments used to help to control the landing sequence will provide data that will also be useful scientifically, such as a pressure profile of the atmosphere.

Good luck
Anthropomorphizing machines is obviously silly…but what the hell!

Good luck, Curiosity!