Future Space Missions and Biohazard Implications

Karen J. Meech

Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI, 96822

Abstract In the era of new, more streamlined NASA missions, there is an exciting suite of smaller more frequent missions, including those in the Discovery line, and in the new Mars Exploration initiatives. The growing field of Bioastronomy combines the studies of planetary astronomy, astrophysics, and biology in an exciting field which encompasses the search for extra-solar planetary systems, the study of extreme environments on Earth and other solar system planets and moons where life might exist, the origin and evolution of life, and the search for extra-terrestrial intelligence. Planned and proposed future NASA missions are more and more strongly combining astronomy and biology in their mission goals. This paper will focus discussion on two missions: the NASA Deep Impact Mission, as well as the results from current Mars exploration and plans for future Mars sample return. Relevant issues related to biohazards and these missions will be discussed. Introduction The NASA Discovery Program The Discovery program was established as the implementation of NASA Administrator Dan Goldin's vision for planetary missions. In contrast to the old multi-billion dollar style of missions which were very large in scope, carrying many instruments and involving large groups of people during many years, the Discovery program launches many small missions that are focussed on science with a fast turn around (with launches every 12-24 months), costing less than 299 million. This is an ongoing program which offers opportunities for members of the scientific community to propose for the entire mission. The overall goal of the Discovery program is to provide answers to fundamental planetary science questions and therefore enhance our understanding of the solar system and its origins. To date there have been eight Discovery missions selected, of which one has been a mission to Mars (Pathfinder) and 3 are comet missions, including the Stardust mission to collect dust samples from comet 81P/Wild 2, the CONTOUR comet nucleus tour of 3 comets, and the Deep Impact Mission which will conduct a cratering experiment at comet 9P/Tempel 1. The NASA Mars Architecture The primary goals of NASA's suite of Mars exploration missions is to understand the potential for life on Mars and elsewhere in the Universe. In addition, by studying Mars, we hope to understand the processes of and relationship between Mars and Earth climate changes, to understand the interior structure of Mars and how it relates to its geology and geophysics and to assess Mars as a site for resources for future exploration. These goals are linked together via a common thread, involving the theme of following the water on Mars. Eventually, plans include a robotic sample return from Mars, possibly as early as 2011. A sample return is essential in order to provide a controlled environment for repeat analysis of samples, to give us the flexibilty of a wide range of instrumentation. Only by analyzing samples on Earth can we accommodate unforseen results and adapt the investigation to the findings. However, especially since Mars is an environment which was once suitable for life, we need to assess the risk to Earth from biological contamination.

Results of Previous Mars Missions Table 1 highlights the previous Mars missions and their results. Prior to 1976, there were 21 US and USSR missions to Mars, roughly half of which were successful. The goals of the early missions were to characterize the planet by studying the surface and atmosphere with investigations relevant to the search for life and to begin to establish technologies for long-duration missions. While the earliest missions gave us pictures of Mars and some physical data, the Viking missions gave us the most complete picture of the planet, showing a hemispherical dichotomy, evidence for past surface water and volcanism, but not life. Mars Pathfinder - The Mars Pathfinder mission [1] was the second Discovery mission, and the first one to arrive at its target. Although the mission was largely a technology demonstration mission, with a primary mission duration of 1 month beginning 7/4/97, it also had several science objectives. This highly successful mission showed that Mars had a wet warm history 4.5 billion years ago, and revealed an unexpected chemical composition for the surface rocks which revised ideas of volcanism on Mars. In addition, detailed atmospheric measurements were made of dust opacity, and diurnal changes in temperature and pressure.

Fig. 1. Mars Pathfinder landing site located at 19.33 N, 33.55W in the Ares Vallis area, 850 km SE of the Viking landing site. The site was at the edge of a large ancient flood plain, where it was hoped to find a variety of rock types.

Mars Global Surveyor - The Mars Global Surveyor (MGS) mission [2], which is ongoing, has been a spectacular success and is revolutionizing our ideas about Mars. Launched on November 7, 1996, after 20 years with no successful Mars missions, the spacecraft carries 4 instruments: a wide angle Mars Orbital Camera (MOC), a Mars Orbiter Laser Altimeter (MOLA) which uses reflected laser light to measure topography, a Thermal Emission Spectrometer (TES) which will map the mineral composition of the surface, and a magnetometer to study the planet's global magnetic properties. The spacecraft arrived at Mars on 9/11/97 and began its aerobraking maneuvers on 9/17. The start of the Mars mapping mission began during March 1999. The primary mapping mission was one year duration to be followed by use of the spacecraft as a future Mars mission communications relay. However, the science investigations are continuing. The ten most significant science highlights from the first year of mapping are listed below [2].

• Remnant Magnetization - The remnant magnetic signatures preserved in the crust show that Mars previously had a magnetic field, implying that it had a molten core.

• Global Topographic Model - Prior to the MGS mission, the topography of Mars was known only within a kilometer; now we have accuracies of 0.5m from MOLA. The topographic maps show a 30km topographic dynamic range with significant hemispherical dichotomy. The southern hemisphere is elevated and the northern hemisphere depressed below the mean surface model. There is the possibility that the flat northern hemisphere may once have been the site of a global ocean.

• Crust/Lithosphere Structure - We now have the first good global models of the structure of the Martian crust and underlying layers, showing that the interior layers do not show the same global dichotomy as the topographic map.

• Crustal Evolution - The TES has shown distinctive evolutionary regions on the surface, with different composition elements.

• Layered Strata - Valles Marineris - Layering is widespread on Mars, and may suggest that volcanism played a much larger role in the history of the planet than was previously believed.

• Hydrothermal Environments - Possible detection of the mineral hematite, may indicate possible past hydrothermal environments.

• Complex Erosional History - There is now a much greater understanding of dust transport on Mars and its influence on the erosional history of the planet.

• Polar Caps - Water Inventory - We now have the first good estimates of the surface water inventory from the polar regions.

• Origins of Channels - Detailed MOC images show regions of apparent sapping of near-surface liquid water, from possible melting of ground ice. These gullies are found in the walls of relatively young impact craters at middle and high Martian latitudes, which suggest that these may be recent events [3].

• Cloud Measurements - From detailed measurements of the atmosphere, the mission investigators have been able to develop much more detailed global atmospheric models.

Fig. 2. Seepage in wall of 7km crater located near 41.1 S and 159.8 W, which may represent the outflow of 2.5 million liters of water [4].

With the recent losses of the Mars Climate Orbiter (MCO) and Mars Polar Lander (MPL) missions, NASA has undertaken a re-evaluation of its Mars Exploration Strategy, and has come up with a less aggressive, slower, but much more technically sound program to continue explorations of the red planet. The plan calls for continued launches at each launch window opportunity, beginning with the successful recent launch of the 2001 Mars Odyssey Orbiter on April 7, 2001. This mission carries 3 instruments -- a thermal emission imager, a gamma ray spectrometer and the Mars Radiation Environment experiment. The instruments will make global observations to gain a better understanding of Mars past climate and geologic history, including the search for water. This mission will be followed by the launch of twin Mars exploration rovers in 2003, the Mars Reconnaissance Orbiter in 2005 (which will recover the science lost with MCO), a Mobile Scientific Laboratory and small scout missions in 2007, and the possibility of a communications satellite and a small network of landers in 2009, with a sample return in the beginning of the second decade of the 21st century.

Table 1. Previous, Current, Future Mars Missions & Status

Duration Mission Country Goals

07/88-03/89

Phobos 1&2

L-USSR • investigate interplanetary environment • Mars atmosphere • Phobos surface composition

08/75-11/82

Viking 1&2

US

• image entire surface 150-300m resolution • surface samples searched for life • atmosphere composition & meteorology • seismometers

09/92-08/93 Mars Observer L-US • Mars geoscience & climate 11/96-11/96 Mars 96 L-USSR • orbiter & surface penetrators

12/96-03/98

Pathfinder

US

• Landing technology demonstration • Atmosphere & meteorology • Surface rock composition

11/96-ongoing

Mars Global Surveyor

US

• Recovery for Mars Observer • Topography, gravity, Mars interior • weather, climate & info • Role of water in Mars history

12/98-09/99

Mars Climate Orbiter

L-US

• Mars weather, climate • H2O/CO2 budgets • Long-term climate changes

07/98-12/03 Nozomi Japan • Upper Mars atmosphere / solar wind

01/99-12/99

Mars Polar Lander

L-US • Record atm conditions near S pole • Polar deposit volatiles

04/07/01 Mars Odyssey US • Mars Orbiter 05/03&06/03 Mars Exploration Rovers US • Two Mars Rovers

06/01/03

Mars Express

ESA

• Mars Orbiter & Lander • Mineral study of surface • Study radiation environment

07/05

Mars Reconnaissance Orbiter

US

• Mars Orbiter • High resolution measurements • Past or present evidence of water

Late 07 Mars 2007 US • Mobile Science Lab, small Scout Missions Late 07 Mars Netlanders CNES • Communications network

Late 09

Mars 2007

US • Comm Satellite, Small Net-Landers • SAR (radar) satellite (Italy)

Notes: L = Mission lost Because of the past history of Mars, which suggests the possibility that the climate may have been conducive to life, it is appropriate to examine the potential biohazard implications of bringing back material from Mars now, well in advance of the first samples. The Deep Impact Mission Introduction Cometary nuclei are the most pristine objects from the era of planetary formation that are observable at close range, and as such, they provide a link to study the birth and evolution of the Solar System through their compositional and physical properties. Studies of comets are telling us how much the interstellar material is processed in the solar nebula prior to its incorporation into planetary bodies. However, numerous close solar perihelion passages will deplete the surface layers of volatiles -- up to depths as much as 10m [5]. Comets have also played a role in bringing volatiles to early Earth [6] and possibly organic materials which lead to the emergence of life [7,8]. While there have been missions to comet 1P/Halley,

and there are several other comet missions planned by the US and other countries, these missions look at cometary surface properties and the surface layers, which may have been significantly altered since the time of formation [9]. The eighth Discovery mission Deep Impact, will be launched in Jan 2004, for an encounter with comet 9P/Tempel 1 in early Jul 2005, and is a unique mission designed to sample deeply below the surface of a comet and examine the most primordial composition. The spacecraft will deliver a 350kg impactor to the nucleus to excavate a crater 20m deep and 100m in diameter. The instrumentation complement includes a high resolution imager/spectrograph (HRI) and a medium resolution imager (MRI) in the visible and near-infrared. The MRI will provide the scientific context of the mission (along with simultaneous ground-based observations), and will image the ejecta plume and perform the targeting. The HRI will provide high resolution images and spectra (for compositional analysis) of the dust and gas cloud surrounding the comet, and the impact crater in both the visible and the infrared. Science Objectives The goal of the mission is to excavate a crater to depths below the evolved surface layer and examine pristine material which comes from the interior. In spite of several previous and ongoing comet missions, we actually know very little about comet nucleus properties. The size and time of formation of the crater is sensitive to cometary properties. If the crater formation is dominated by the strength of the surface material rather than gravity ( i.e. the energy goes into breaking bonds rather than lifting material), the crater will be smaller and have a larger depth/diameter ratio. The final crater size, depth and time of formation will provide constraints on the comet bulk density and surface material porosity. In addition, models of the depth of surface material alteration from repeated passages close to the sun, suggests that the depth of our crater should penetrate into material which may not have been significantly thermally altered since the time of formation. We will observe both from the spacecraft and the ground any changes in the quantity and chemical composition of the outgassed materials after the impact, with the aim of understanding the primordial composition of the comet. The molecules of primary interest are those that exist as abundant ices in the nucleus – H2O, CO and CO2 . The Mission Target We are beginning to accumulate a large amount of ground-based data about the mission target, comet 9P/Tempel 1. Between the present time and the encounter, we plan to characterize the rotation state of the nucleus, determine its size and albedo, look for reflectivity variations on the surface, determine the outgassing rate of various species, and model the dust environment of the coma. This will involve a large coordinated international ground-based observing effort, and a massive data reduction and analysis program. Nucleus size and Albedo - Knowledge of the nucleus size and reflectivity (or albedo) determines a comet's brightness, critical for targeting the impactor, developing navigation models, the MRI and HRI instrument specifications and planning the imaging sequences from which exposure times will be set. Just past the comet's perihelion passage in 2000, we obtained simultaneous visible and infrared data to model the size and reflectivity of the nucleus. From these observations we have determined a nucleus size RN equal to 2.6 ± 0.5km and a reflectivity of 4% [10]. Rotation State of the Nucleus - Our mission specifications require that the rotation period be "long'' so that we can image the impact and final crater for 850s post-formation without the crater rotating out of the field of view. In order to do this, we need to be able to predict the rotational phase of the nucleus at impact with an accuracy better than ± 20% prior to the 1/05 Earth encounter (the last time to affect the impact time). This will allow optimization of the impact time so that the nucleus will present the largest lighted target area. An international observing campaign during the fall of 2000, involving 8 telescopes in both hemispheres and over 60 nights of data has lead to a preliminary rotation period determination of 42 hours using Fourier techniques. To allow sufficient time for mission planning and operations, we must achieve an accuracy of ± 0.6 min in the 42 hr rotation period and tie down the reference rotational phase in early 2004. Getting this accuracy in

the period is difficult. When the comet is free from its cloud of dust and gas which obscures the signature from the nucleus, it is also very far from the sun and very faint, requiring the world's largest telescopes to detect its signal. In addition, because of outgassing from comets which can affect the angular momentum of the nucleus, these comets may not be in a simple state of rotation, but rather in a complex motion, which necessitates a much longer time base of observations to model the rotation. We have another major international observing campaign planned for Fall 2001, which should allow us to achieve our desired accuracy.

a. b.

Fig. 3. a. Rotational brightness modulation from the nucleus of comet 9P/Tempel 1 [11]. b. Image of the comet from 8/00, when the comet was at 2.5AU from the sun.

Finally, we need to improve our knowledge of the shape and pole orientation of the nucleus as an input to the final data taking sequence strategy which will be determined after Earth flyby. This requires coma-free light curve amplitudes at as wide a range of observing geometries as possible. We don't expect a complete model of the nucleus shape, but we will significantly narrow the contraints on shape. Relation to Understanding Impact Hazards Understanding the impact cratering process is very important because Earth resides in a swarm of comets, asteroids and debris which can impact the surface. The mass extinction (of 70% of all species, including dinosaurs) 65 million years ago at the Cretaceous-Tertiary boundary (KT) was probably due to the impact of a 10 km body at Chixulub in the Yucatan peninsula of Mexico [12]. Only part of the devastation from an impact is caused by the explosion itself, and perhaps a more significant effect comes from the post-impact global effects on climate. Although the size distribution of the potentially, Earth-intersecting space debris is such that most objects are small enough to burn up harmlessly in Earth's atmosphere, there is a finite probability that something large enough to cause significant damage or even global catastrophe could impact Earth [13]. Most of our knowledge about impact-cratering comes from studying impact craters on Earth and the Moon, and from experiments using explosives. We have had very little opportunity to observe a naturally-occurring comet impact (a notable exception to this was the break up and impact of comet D/Shoemaker-Levy 9 into the atmosphere of Jupiter in July 1994). Although small on cosmic scales, the 19 Gigajoule (equivalent to 3 tons TNT) comet 9P/Tempel 1 impact will excavate a sizeable crater and give us invaluable confirmation of cratering physics scaling laws in regimes where they have not been tested (low gravity, and highly porous material). In addition, the highly visible public event will create an important awareness about the necessity for ground-based monitoring to

search for a network of survey programs to search for Near-Earth-Objects which could pose a potential hazard to Earth. There is currently a program called Spaceguard (adopted by NASA in 1998) which has as its goal the detection of 90 of all Near-Earth-Asteroids larger than 1 km in diameter within a decade. While objects smaller than this can cause damage, this is the size which poses the greatest hazard in terms of global effects [14]. For energies above this threshold (1 million megatons of TNT), the individual risk from impacts increases by an order of magnitude because of the global effects.

a.

b.

Fig. 4. [a] Hubble Space Telescope image of comet Shoemaker-Levy 9 before impact [H. Weaver], [b] Painting by Don Davis illustrating what the impact of a large planetesimal on the early

Earth would have looked like.

Mars Sample Return Life Requirements and the Early Mars Environment Although there is no universal definition of what constitutes life, life has the ability to grow, replicate and evolve. Life as we know it is based on organic carbon, which makes up a diverse suite of chemicals. In order to bring atoms close enough together to create this diversity of complex molecules, it is believed that the evolution life requires a liquid medium. Liquids also are important for bringing nutrients to living organisms, and for removal of wastes. Life also requires a source of energy. There are many interesting environments within our solar system where current conditions may not exclude the possibility of life. These include Mars (subsurface), Jovian satellite Europa's oceans, and interesting prebiotic chemistry on Saturn's moon Titan. Current explorations of diverse habitats on Earth have shown that microbial life can survive under extreme conditions thriving in extreme ranges of temperature, pH ranges, salinity, dessication, and pressure [15]. It is possible that life on Earth got its start in the hot plumes of mineral rich water surrounding deep ocean hydrothermal vents, and this is a potential model for life on early Mars [16]. Even current Mars conditions as shown in Table 2 are not that different from conditions on Earth where cold-loving micro-organisms are known to thrive, such as in Antarctic dry valley lakes. Lake Vostok, a large body of water buried beneath 4 km of glacial ice, is one of 76 known sub-glacial Antarctic lakes. Ice cores have been obtained to within 120 m of the lake surface, and viable organisms have been found to depths of 2,400 m, species which had never been seen before [17].

Table 2. Current Mars Conditions.

Characteristic Description Atmospheric Composition CO2 [95%], N2 [3%]

Atmospheric Pressure 0.006 bar Mean Temperature < 0 °C

UV protection None { lack of ozone }

General Environment Highly oxidized,

Viking showed no organics to 109 gm-1 There are a wide range of surface features on Mars which point to a past history in which the climate was consistent with warmer conditions that would allow for liquid water on the surface, however it is still uncertain whether this reflected a sustained period of a warm wet climate or episodic events. These features include sinuous channels consistent with sustained periods of rainfall, dated to approximately 3.5-3.9 billion years, water erosion features, flow features around impact craters, and evidence for massive water outflows from regions of chaotic terrain (see Fig 5a.). In August 1996 there was an exciting announcement that a Martian meteorite collected in the Antarctic meteorite research program, ALH84001, had possible evidence of life [18]. There were four pieces of evidence which led to this conclusion: [i] the presence of carbonates, known to be created in Earth-based biological processes, [ii] the presence of two minerals, FeS and magnetite which do not coexist on Earth outside of biological dis-equilibrium processes, [iii] the presence of complex hydrocarbons (PAH's) and [iv] nm-sized structures which looked like microfossils. The authors argued that while any individual line of evidence was not compelling evidence for life, the presence of four together made a possible case. While it seems unlikely that this meteorite contained life, the debate and analysis of the sample continues. Science From Mars Samples -- The Need for Sample Return Given the expense, complexity and potential biological hazard implications of bringing back samples from Mars, it is prudent to assess the need to bring back such samples -- especially as we already have samples of the Mars surface on Earth. One of the strongest concerns in the controversy about life in ALH84001 is possible terrestrial contamination -- which is present in other Mars meteorite samples. Secondly, there is an enormous benefits from a terrestrial lab, not only for the variety of experiments that can be conducted, but also since the precision by which we can make measurements is significantly better (102-103 times) on Earth than in a mission experiment. Some sample preparations are difficult in-situ, and other tests (e.g., some age-dating techniques) are impossible to conduct in-situ. Finally, without knowing where the rock sample is from (as in the case of the Mars meteorites), we lose the geological and climatological context,

which could be critical to assess the potential for life in the sample. It should also be noted that ALH84001 has now been analysed by over 100 metric tons of equipment (still ongoing), and the answer is still not in!

a.

b.

c.

Fig. 5. a. Viking 1 orbiter images of Parana Valles a valley network drainage system. Image is 250 km across. [Viking Orbiter 084A47, NASA].

b. Image of Martian meteorite ALH84001 [Image from Johnson Space Center], c. Structures in ALH84001 interpreted to be fossils [18].

Biological Concerns Although the current environmental conditions on Mars suggest that the likelihood of extant life is very small, there are important planetary protection issues that must be addressed. Before any sample return mission, we must consider and take responsibility for protection of Earth against potential microorganisms (back contamination), and also to avoid contaminating the worlds we visit (forward contamination). These concerns dictate the design of sample transport to Earth, as well as the collection and containment facilities to study the sample -- including issues related to sterilization and distribution of the samples. Extremists in the areas of biohazards are quick to point out that smallpox in America killed tens of thousands, European explorers arriving in Polynesian and Hawaii brought diseases with a 50% fatality and from 1347-1350 nearly 25% of Europe's population died from the strange new microbes that caused the epidemic we know as the Black Death. Public concern extrapolates to worries about the virulence of potential extraterrestrial organisms. In reality, the risk of any pathogenic traits from supposed extraterrestrial life forms are very low, since harmful interactions occur because the pathogen has evolved along similar pathways to take advantage of and interfere with its host [19]. In addition, any life-forms which did not evolve on Earth are not likely to cause ecological distruption as they will be unable to compete with terrestrial life. Finally, it is considered that we already receive between 15-300 Mars meteorites on Earth per year through falls, and a small percentage of these aren't sterilized by their transit through space and passage through the atmosphere. However, because the risk can never be described as zero, sample return programs must be prudent to reduce any publicly perceived risk to an acceptable level. Protocols and Procedures -- Life Detection The plan for return of Mars samples involves collection of material from the Martian surface, capture in Mars Orbit and transfer to Earth. A alternative to bringing back samples and worrying about the quarantine process is to study samples on the space station. However, aerocapture techniques in Earth orbit are very difficult. In addition this does not avoid the issue of biocontamination since there would be humans involved in the investigations aboard the space station, and humans are hard to decontaminate. Although similar issues arose in the mid-1960's with the return of lunar rock samples, it is important to learn from the mistakes made in the quarantine process from the Apollo program. The construction of the quarantine facility began in 1966 -- only 3 years before the proposed return of samples -- which was insufficient time to develop and test the facility. In addition, there was the perceived notion that the samples had to be kept in an environment which closely matched the lunar environment, a hard vacuum , and this proved impossible. Based on the lunar experience, it is sensible to keep things as simple as possible, i.e., to not worry about preserving the Martian environment (low temperatures, pressures) during the study of the samples, and to perform only those experiments on the samples in quarantine which relate to biological search. The sample-receiving facility should have the maximum biological containment capabilities (equivalent to the bio-level safety-4 labs currently used) to prevent back-contamination, but should also maintain the integrity of the samples ( e.g. a clean room to prevent forward-contamination). Once the samples are certified as "safe'', they could be released for in-depth analysis ( e.g., geological studies, climatological studies, chemical analysis, radiometric dating etc.) [19]. Based on our understanding of biology, life elsewhere probably consists of the same chemical elements as life on Earth. The starting point to search for the potential for life may be to search for organic carbon, however, that in itself is not an indication of life, since we know that organic material is prevalent in the outer solar system, and in the asteroid belt -- a source of much material falling on the Martian surface [20]. Isotopic signatures can also be indicators of life. Life chemistry is based on a fundamental asymmetry: living systems make use of only one of two mirror image forms of organic molecules -- using the left-handed form of amino acids and the right handed form of sugars. This single-handedness, or homochirality, is a fundamental property of life, and searching for homochiral organic compounds (assuming that the sample has not been heated above 150 °C) can be an indication of past/present life. If the life preserved in samples is very old and degraded, it is still possible to look for chemical "biomarkers'', or the molecular fossils related to biologic chemistry.

It is unlikely that there will be definitive proof of life found in the samples returned from Mars, more likely the results will be ambiguous. In this case decisions will be necessary about sterilization and release of samples to the community for further studies. There are 2 methods of sterilization -- heating and radiation. What is in question is the minimum amount of sterilization needed to lower the risk to acceptable levels without damaging the sample. Unless heated to incandescence (which guarantees sterilization!), moderate heating will not destroy geological information in the samples, but it can reset isotopic information which will impact information on past Martian climate (from the trapped gases), and it will certainly harm aqueous minerals. Possible homochirality of organic material is lost near 150 °C, and near 275 °C possible fossil structures will breakdown. The situation with sterilization by radiation ( X-rays) is much less certain; the effects of radiation on the intended science investigations has not been studied. In addition, it is known that there are some very radiation-resistant bacteria -- bacteria from Earth survived 2.5 years on Surveyor 3, and the Long Duration Exposure Facility (LDEF) in Earth orbit had viable spores after 7 years in orbit in a harsh radiation environment. Conclusions This brief discussion has highlighted some of the recent and upcoming mission results and strategies for missions to Mars and comets which have bearing on issues related to Earth physical and biological hazards. We can see that the new NASA architecture provides some faster, less expensive programs which will provide, not only fundamental information about the early solar system, its orgins and the origin of life, but also will yield interesting new information relevant to the continued existence of life on Earth. References [1] Mars Pathfinder website: http://mpfwww.jpl.nasa.gov/MPF/default.html [2] Mars Global Surveyor Webpage: http://mars.jpl.nasa.gov/mgs/ [3] M.C. Malin, K.S. Edgett, 2000. Evidence for Recent Groundwater Seepage and Surface Runoff on

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