Mission Objectives Overview===========================The Mars Express orbiter was equipped with the following selectedpayload complement, representing about 116 kg in mass, with thefollowing associated broad scientific objectives:Energetic Neutral Atoms Imager   ASPERA- Study of interaction of the upper atmosphere with the  interplanetary medium and solar wind.- Characterisation of the near-Mars plasma and neutral gas  environment.High-Resolution Stereo Camera   HRSC- Characterisation of the surface structure and morphology at high  spatial resolution  (up to 10 m/pixel) and super resolution (up to 2 m/pixel).- Characterisation of the surface topography at high spatial and  vertical resolution.- Terrain compositional classification.Radio Science Experiment   MaRS -- Characterisation of the atmospheric vertical density, pressure, and  temperature profiles as a function of height.- Derivation of vertical ionospheric electron density profiles.- Determination of dielectric and scattering properties of the  surface in specific target areas.- Study of gravity anomalies.- Study of the solar corona.Mars Advanced Radar for Subsurface and Ionosphere Sounding   MARSIS- Study of the subsurface structure at km scale down to the  permafrost.- Mapping of the distribution of water detected in the upper portions  of the crust.- Characterisation of the surface roughness and topography.Lander Communications Package   MELACOM- This telecommunications subsystem constitutes the data relay  payload of Mars Express.- Its primary mission was to provide the data services for the  Beagle-2 lander.- It was designed to relay at least 10 Mbits of information per day.IR Mineralogical Mapping Spectrometer   OMEGA- Global mineralogical mapping at 100-m resolution.- Identification and characterisation of specific mineral and  molecular phases of the surface.- Identification and characterisation of photometric units.- Mapping of their spatial distribution and abundance.- Study of the time and space distribution of atmospheric particles.Planetary Fourier Spectrometer   PFS- Characterisation of the global atmospheric circulation.- Mapping of the atmospheric composition.- Study of the mineralogical composition and of surface atmosphere  interactions.UV and IR Atmospheric Spectrometer   SPICAM- Study of the global structure and composition of the Martian  atmosphere.- Study of surface-atmosphere interactions.Visual Monitoring Camera   VMC- Stand-alone digital camera to take colour snapshots of the Beagle  lander.- Operation of this camera will occur during separation of the landerGeochemistry and Exobiology Lander  BEAGLE-2The top-level scientific objectives of the lander are:  - Geological investigation of the local terrain and rocks (light    element chemistry, composition, mineralogy, petrology, age).  - Investigation of the oxidation state of the Martian surface.  - Full characterisation of the atmospheric composition.  - Search for criteria that demonstrated life processes appeared in    the past.  - Determination of trace atmospheric gases.When folded up Beagle 2 resembles a pocket watch. However, as soon asit comes to a halt on the Martian surface its outer casting will opento reveal the inner workings. Firstly the solar panels will unfold -catching sunlight the charge the batteries which will power thelander and its experiments throughout the mission. Next, a roboticarm will spring to life. Attached to the end of the arm is the PAW(Position Adjustable Workload) where most of the experiments arelocated. These include a pair of stereo cameras, a microscope, twotypes of spectrometer, and a torch to illuminate surfaces. The PAWalso houses the corer/grinder and the mole, two devices forcollecting rock and soil samples for analysis.Scientific Objectives Gas Analysis Package  This is where investigations most relevant to detecting past or  present life will be conducted. The instrument has twelve ovens in  which rock and soil samples can be heated gradually in the presence  of oxygen. The carbon dioxide generated at each temperature will be  delivered to a mass spectrometer, which will measure its abundance  and the ratio of carbon-12 to carbon-13. The mass spectrometer will  also study other elements and look for methane in samples of  atmosphere. The temperature at which the carbon dioxide is  generated will reveal its nature, as different carbon bearing  materials combust at different temperatures. Environmental sensors   A variety of tiny sensors scattered about the Beagle 2 lander will   measure different aspects of the Martian environment including   atmospheric pressure ,air temperature and wind speed and   direction; ultra-violet (UV radiation; dust fall out and the   density and pressure of the upper atmosphere during Beagle 2's   descent through the atmosphere. Two stereo cameras   The cameras will provide digital pictures from which a 3D model of   the area within the reach of the robotic arm may be constructed.   As the PAW cannot be operated in real time from Earth, this 3D   model will be used to guide the instruments into position   alongside target rocks and soil and to provide information on the   geological setting of the landing site. Microscope  The microscope will pick out features a few thousandths of a  millimetre across on rock surfaces exposed by the grinder. It will  reveal the texture of the rock, which will help determine whether  it is of sedimentary or volcanic origin. Mossbauer Spectrometer  It will investigate the mineral composition of rocks by irradiating  exposed rock surfaces and soil with gamma rays emitted by an  isotopic source, cobalt-57, and then measuring the spectrum of the  gamma-rays reflected back. In particular, the nature of the iron  minerals in the pristine interior and weathered surface of the  rocks will be compared to determine the oxidising nature of the  present atmosphere. X-ray spectrometer  This will measure the elemental composition of rocks by bombarding  exposed rock surfaces with X-rays from four radioactive sources  (two iron-55 and two cadmium-109). The rocks will emit lower energy  X-rays characteristic of the elements present. Rock ages will be  estimated using the property that the isotope potassium-40 decays  to argon-40. The X-ray spectrometer will provide the potassium  measure and the GAP will measure argon trapped in rocks. Mole  The mole will be able to crawl up to several metres across the  surface at a rate of 1cm every six seconds. Once it has reached a  boulder, it will burrow underground to collect samples in a cavity  in its tip. Alternatively, the PAW can be positioned such that the  mole will burrow underground to collect samples possibly 1.5m below  the surface. Corer/Grinder   The corer/grinder consists of a drill bit which can either be   moved over a surface to remove weathered material, or be   positioned in one spot to drill a core of hopefully pristine   samples.