On Mars

The coupled methods, GC/MS and LC/MS, form very powerful combinations for simultaneous separation and identification of components of mixtures. Hence, these techniques have been used in such widely disparate enterprises as looking for evidence of life forms on Mars and for testing racehorses or athletes for the presence of banned drugs. 

Heaviside s last years were spent as an embittered recluse at Torquay, Devon where he allowed only a few people to visit him. For much of his life he suffered from recurring jaundice that was to prove fatal. He died on February 3, 1925. Heaviside s work has been an inspiration to countless electrical engineers and mathematicians. Time has enhanced the esteem in which he is held succeeding generations have spent many hours studying his writings. As a lasting honor, craters on Mars and the Earth s moon were named after him. 

A.26 Mars orbits the Sun at 25 km-s. A spaceship attempting to land on Mars must match its orbital speed. If the mass of the spaceship is 2.5 X 1(T kg, what is its kinetic energy when its speed has matched that of Mars ... 

Sublimation is the direct conversion of a solid into its vapor. Frost disappears on a cold, dry morning as the ice sublimes directly into water vapor. Solid carbon dioxide also sublimes, which is why it is called dry ice. Each winter on Mars, solid carbon dioxide is deposited as polar frost, which sublimes when the feeble summer arrives (Fig. 6.24). The enthalpy of sublimation, AHsub, is the molar enthalpy change when a solid sublimes ... 

FIGURE 6.24 The polar ice caps on Mars extend and recede with the seasons. They are mostly solid carbon dioxide and form by direct conversion of the gas into a solid. They disappear by sublimation. Although some water ice is also present in the polar caps, the temperature on Mars never becomes high enough to melt it. On Mars, ice is just another rock. 

Speculation about life on other planets probably began when humans discovered that the Earth Is not unique. We know that several other planets of the solar system bear at least some resemblance to our own. Why, then, should there not be life on Mars, or Venus, or perhaps on undiscovered Earthlike planets orbiting some other star ... 

The photo below, taken by the Ttl/ng spacecraft, shows that the surface of Mars has been eroded, apparently by liquid water. More recent photos transmitted by Spirit and Opportunity convince scientists that this was the case. Apparently, Mars was once much warmer than it is today. Planetary scientists speculate that at one time the atmosphere of Mars may have contained large amounts of carbon dioxide, setting up a greenhouse effect that made the surface of that planet warmer and wetter. Might there, then, have been life on Mars at some earlier time Molecular stmctures found in meteorites thought to come from Mars have been interpreted to show that there was once life there, but these results are controversial. 

Tung HC, NE Bramall, PB Price (2005) Microbial origin of excess methane in glacial ice and implications for life on Mars. Proc Natl Acad Sci USA 102 18292-18296. 

The fourth example, the use of chemical processing on Mars for producing a propellant, is presented in Section 1.9.7 [106]. The fifth and last example describes the use of distributed systems for global carbon dioxide management, aiming at reducing the greenhouse effect [106]. The main issue here is the installation of gas-absorption equipment for CO2 capture at central, fossil-fuel power plants. 

TeGeotenhuis, W. E., Wegeng, R. S., VanderWiel, D. P., Whyatt, G. A., ViSWANATHAN, V. V, ScHIELKE, K. P., Sanders, G. B., Peters, T. A., Microreactor system design for NASA in situ propellant production plant on mars, in Proceedings of the 4th International Conference on Microreaction Technology, IMRET 4, pp. 343-3350 (5-9 March 2000), AIChE Topical Conf Proc., Atlanta, USA. 

Physically, the MIMOS II Mossbauer spectrometer has two components that are joined by an interconnect cable the sensor head (SH) and electronics printed-circuit board (PCB). On MER, the SH is located at the end of the Instrument Deployment Device (IDD) and the electronics board is located in an electronics box inside the rover body. On Mars-Express Beagle-2, a European Space Agency (ESA) mission in 2003, the SH was mounted also on a robotic arm integrated to the Position... 

MIMOS II has three temperature sensors one on the electronics board and two on the SH. One temperature sensor in the SH is mounted near the internal reference absorber, and the measured temperature is associated with the reference absorber and the internal volume of the SH. The other sensor is mounted outside the SH at the contact ring assembly. It gives the approximate analysis temperature for the sample on the Martian surface. This temperature is used to route the Mossbauer data to the different temperature intervals (maximum of 13, with the temperature width software selectable) assigned in memory areas. Shown in Fig. 3.21 are the data of the three temperature sensors taken on Mars (rover Opportunity at Meridiani Planum) in January 2004 between 12 10 PM on Sol 10 (10 Martian days after landing) and 11 30 AM on Sol 11. The temperature of the electronics board inside the rover is much higher than the temperatures inside the SH and the contact plate sensor, which are nearly identical and at ambient Martian temperature. 

An example of a simulated overnight experiment on Mars is shown in Fig. 3.22 for eight temperature intervals using the Compositional Calibration Target (CCT made out of magnetite rock slab) on the rover as the target. In the case of contact-ring temperature sensor failure, the internal temperature sensor would be used (software selectable). 

Fig. 3.22 Backscatter MIMOS II spectra collected in eight temperature intervals on the CCT target (magnetite rock) during a simulated overnight Mossbauer experiment on Mars...

One Mossbauer spectrum consists of 512 velocity channels (3 bytes per channel). One temperature interval consists of five Mossbauer spectra (one for each detector). There are 13 temperature intervals with selectable width. Thus, MIMOS II can accumulate simultaneously up to 65 Mossbauer spectra during one experiment session on Mars. All Mossbauer, energy, engineering, and temperature data taken during this session are stored in a volatile SRAM (Static Random Access... 

During the mission, the magnetite CCT was measured in several runs to verify the functionality of MIMOS II. The well-known Mossbauer parameters of magnetite were used for velocity calibration, as shown in Fig. 3.22 for different temperatures. This kind of measurement was done in the laboratory with the flight units as a function of temperature to be used as a reference for the measurements on Mars. Figure 3.22 shows the Mossbauer spectra of the CCT at different mean temperatures. 

Fig. 8.31 Left) In the Mossbauer spectrum taken in the Columbia Hills at a rock called Clovis the mineral goethite (GT) (a-FeOOH) could be identified. GT is a clear mineralogical evidence for aqueous processes on Mars. Right) The rock Clovis is made out of rather soft material as indicated by the electric drill-current when drilling the - - I cm deep hole seen in the picture. Drill fines are of brownish color. The pattern to the right of the drill hole was made by bmshing the dust off the surface by using the RAT...

Fig. 8.34 Lefty, outcrop rocks found at the crater wall of Eagle Crater, where the rover Opportunity landed on 24 January 2004. Clearly, the sedimentary structure is seen. Right) in the spectrum, taken on sol 33 (sol = Martian day) of the mission, the mineral Jarosite, an Fe -sulfate, could be identified at the Meridiani Planum landing site. It forms only under aqueous conditions at low pH (< 3 ) and is therefore clear mineralogical evidence for aqueous processes on Mars...

Meteorites on Mars. Meridiani Planum is the first Iron meteorite discovered on the surface of another planet, at the landing site of the Mars Exploration rover Opportunity [359]. Its maximum dimension is 30 cm (Fig. 8.38). Meteorites on the surface of solar system bodies can provide natural experiments for monitoring weathering processes. On Mars, aqueous alteration processes and physical alteration by Aeolian abrasion, for example, may have shaped the surface of the meteorite, which therefore has been investigated intensively by the MER instruments. Observations at mid-infrared wavelengths with the Mini-TES... 

Recently, sulphur has also been found on the surface of Mars it was probably deposited from the atmosphere and originated in volcanic activity. Sulphur was also found in meteorites which probably originated on Mars (Farquhar et al., 2000). The mean surface temperature is 210 K (at night 150 K and during the day 270 K). 

Fig. 3.1 Perspective view of part of the caldera of Olympus Mons on Mars. This view was obtained from the digital altitude model derived from the stereo channels, from the nadir channel (vertical perspective) and the colour channels on the Mars Express Orbiter. The photograph was taken on 21 January 2004 from a height of 273 km. The vertical face is about 2.5 km high, i.e., about 700 m higher than the north face of the Eiger mountain (Switzerland). With permission of the DLR...

Not only would proof of the existence of life on Mars be a great sensation, but even the discovery of precursors of life, such as biomolecules or building blocks for their formation, would change our perspective greatly (see also Chap. 11). 

The climate on Mars is not so inimical to life as that on Earth s other direct neighbour, Venus. 

Historical events, such as the discovery of the (hypothetical) canals on Mars, led to strong general interest in Mars in the mid-nineteenth century. 

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