Workshop Report On Deep Mars: 

Accessing The Subsurface Of Mars 

On Near-Term Missions

July 2008

NASA/CP–2008-

Compiled and Edited by:

Report of a workshop 

sponsored by and held at 

NASA Ames Research Center 

Moffett Field, California 

on March 1-2, 2008

Stephanie Langhoff

Chief Scientist

Ames Research Center, Moffett Field, California
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Report of a workshop 

sponsored by and held at 

NASA Ames Research Center 

Moffett Field, California 

on March 1-2, 2008

Workshop Report On Deep Mars: 

Accessing The Subsurface Of Mars 

On Near-Term Missions

Compiled and Edited by:

Stephanie Langhoff

Chief Scientist

Ames Research Center, Moffett Field, California
Available from:

NASA Center for AeroSpace Information National Technical Information Service

7115 Standard Drive 5285 Port Royal Road

Hanover, MD 21076-1320 Springfield, VA 22161

(301) 621-0390 (703) 487-4650
Table of Contents

EXECUTIVE SUMMARY.............................................................................................................v

WORKSHOP REPORT

SECTION I. Introduction................................................................................................................1

SECTION II. Science Objectives ...................................................................................................3

SECTION III. Architectures for Drilling Missions.........................................................................9

SECTION IV. Alternatives to Conventional Drilling ...................................................................13

SECTION V. Breakout Sessions...................................................................................................17

GROUP 1: Possible drilling missions in the near term (5 years)......................................................17

GROUP 2: Possible drilling missions in the mid and long term.......................................................18

SECTION VI. Discussion of research priorities and follow-on activities....................................21

AGENDA......................................................................................................................................23

LIST OF PARTICIPANTS............................................................................................................25

iii
iv
On March 1 and 2, 2008, NASA Ames Research Center hosted a two-day weekend workshop 

entitled “Deep Mars: Accessing the Subsurface of Mars on Near-Term Missions.” This workshop is part of a series of informal weekend workshops hosted by the Ames Center Director, 

Pete Worden. The workshop agenda was structured to bring together the science and engineering communities who have a common interest in drilling technologies and exploration of the 

Martian subsurface. 

The agenda blended three major themes: 

(1) The scientific objectives of drilling, such as the search for clues to the existence of past life

and to the geological and climate history of the planet. Key questions are where and how 

deep to drill? Planetary protection issues were stressed as an important consideration in the

design of any drilling mission. 

(2) Architectures for drilling missions that included an overview of most of the current drills in

operation that would be applicable to drilling on Mars. Considerable emphasis was placed on

remote operation and drilling automation technologies. 

(3) Alternatives to conventional drilling included underground moles, horizontal drilling, 

penetrometers, impactors, and access through subsurface cavities. 

In the afternoon of the second day, the participants broke into two groups to discuss possible 

missions that could access the subsurface of Mars in the near term (that could be launched within 

five years) and in the longer term with improvements in technology and with/without human 

involvement.

In the first session focusing on the science objectives, it was noted that the picture we have of 

Mars has significantly changed due to recent scientific studies. For example, the MER rovers 

have found incontrovertible evidence that water once flowed on the surface. Pictures of gullies 

on Mars suggest that outflows of liquid water occur today. Warm spots have been observed on 

the Martian surface and methane has been observed in the Martian atmosphere. Also, recent 

work in astrobiology has shown that microbial activity occurs even at extremely cold temperatures. All of these recent discoveries suggest that life could exist in the shallow subsurface of 

Mars and could be found without drilling to great depths. Therefore, if currently active sites are 

discovered, such as outflows of liquid water, they would be excellent targets for drilling. The 

next best alternative might be an old lakebed where one expects uniform sediment. Drilling missions to both the south and north poles were also suggested. While the scientific objectives and 

required drilling depths would be different for south and north polar missions, the ice would be 

much easier to drill through than surface rock.

Executive Summary

v
Architectures for drilling missions were discussed in considerable depth at the workshop. The 

lunar experience has shown that drilling on planetary surfaces will be challenging even with 

humans in the loop. The difficulty in drilling on Mars is exacerbated by environmental and physical constraints such as low gravity, pressure and temperature, large temperature fluctuations, 

dust storms, and the presence of water ice. Technological challenges such as the transmission 

delays, power and mass restrictions pose additional problems. There was considerable discussion about the current state-of-the-art in autonomous drilling methodology. There was general 

agreement that there needs to be an infusion of technology development funds to bring many of 

the currently operating drills to a higher Technology Readiness Level (TRL).

In addition to conventional vertical drills, other mechanisms for accessing the subsurface of 

Mars were discussed, such as penetrometers that use a hammering or pushing mechanism for 

forward and reverse propulsion, horizontal drills that might be applicable on steep terrain where 

there is recent evidence for liquid water, and impacts to create craters. One interesting possibility is finding natural subsurface cavities, such as lava tubes. The possibility exists that a lava tube 

could evolve into a permanent ice cave lake that could be a safe haven for ice particles, organics 

and microbes trapped for potentially several billion years.

In the breakout sessions the participants discussed the possible missions that could be undertaken in the short and long term. A key observation was that an impactor and/or penetrator mission 

could be done today either as a standalone or add-on mission for relatively low cost. Current 

technology would be able to hit a predetermined target on the surface at a time that the impact 

could be observed by orbiting spacecraft. This could expose the surface below the oxidized 

zone and create a new crater that would be an ideal target for a follow-on drilling mission. This 

mission concept is so compelling that the group decided to write a white paper to describe the 

low-cost impactor mission more fully. In the longer term it was felt that a dedicated drilling mission could achieve a depth of 40–50 m operating the drill autonomously. Human missions could 

probably reach considerably deeper, although this would require a fairly massive drill. However, 

with the next generation heavy launch vehicle such as an Ares V, it would be possible to put such 

payloads on the surface of Mars.

vi
Workshop Report On Deep Mars:

Accessing The Subsurface Of Mars

On Near-Term Missions

Stephanie Langhoff

NASA Ames Research Center, Moffett Field, CA

A workshop entitled “Deep Mars: Accessing the Subsurface of Mars on Near-Term Missions” 

was held at Ames Research Center on 1–2 March 2008. This workshop is part of series of informal 

weekend workshops hosted by the Ames Center Director, Pete Worden. The organizing committee included Stephanie Langhoff, Chris McKay, Carol Stoker, Geoffrey Briggs, Larry Lemke, and 

Brian Glass of Ames Research Center, Tullis Onstott (Princeton), George Cooper (UC, Berkeley), 

Michael Hecht and David Beaty of JPL, and Michael Meyer of NASA Headquarters. The workshop agenda was structured to bring together the science and engineering communities who have 

a common interest in drilling technologies and exploration of the Martian subsurface. Approximately 45 persons representing the government, industry, and academic communities attended 

(see list of attendees). 

The agenda blended three major themes: (1) The scientific objectives of drilling, which center 

around the search for clues to the existence of past life and to the geological and climate history 

of the planet. Key questions are where and how deep to drill? Planetary protection issues were 

stressed as an important consideration in the design of any drilling mission. (2) Architectures for 

drilling missions included an overview of most of the current drills in operation that would be 

applicable to drilling on Mars. Considerable emphasis was placed on remote operation and drilling 

automation technologies. (3) Alternative to conventional drilling that included underground moles, 

penetrometers, horizontal drilling, impactors, and access to the subsurface from subsurface cavities. Except for two 30 minute foundational talks designed to provide overviews of the science 

objectives and drilling architectures, all contributed talks were 15 minutes. Ample time was provided for discussion. The final afternoon was devoted to interactive discussions, organized around 

designing possible missions for subsurface exploration, in the near and longer term.

I. Introduction

II. Science Objectives

To set the stage for the discussion of methods to access the subsurface of Mars, the participants 

first discussed the science objectives, which center around the search for evidence of life. This 

raises questions of where and how deep we need to search and how to accomplish these objectives 

within planetary protection guidelines. We began the session with a presentation by T. C. Onsott. 

He began his overview by noting what we knew (or thought we knew) about the potential for life 

in the subsurface of Mars 10–12 years ago before recent results from the MER rovers and the Mars 

Reconnaissance Orbiter (MRO). We knew then that life prospers in many extreme environments 

on Earth. For example, life is found down to 3 km and in 3 million year old (myr) permafrost. 

On Mars permafrost would lie at great depths (order of kms) at low latitudes and water would lie 

below that. Since the surface of Mars is exposed to ultraviolet and cosmic radiation and is highly 

oxidized (e.g., by hydrogen peroxide), this requires us to look well below the surface to look for 

extant Martians. What is thought to lie beneath the crust of Mars at low latitudes is shown in 

figure 1. The figure suggests that to find extant life at low latitudes one would have to drill a substantial distance through ice and rock.

Figure 1. Based upon the physical properties of the Martian crust down to 5 km at low 

latitudes and the equations of state of H2O and CH4 four different types of environments or 

potential biomes exist in the Martian subsurface. The mean annual surface temperature 

is 218°K and mean annual surface pressure is 6 millibars. The uppermost vadose lies 

above the ice, which sublimates at a depth dependent rate of ~0.03-0.07 m/myr. About 

1.5 meters below that ice surface the pressure is great enough to stabilize clathrates such 

as CH4 clathrates. This mixed clathrate/ice zone may contain pockets of saline down to a 

depth of 2 to 2.5 km at which point brine becomes pervasive. The depth of this permafrost 

zone extends downwards over time at a rate of ~0.5 m/myr as Mars cools. Four distinct 

zones exist under which different metabolic processes and rates can occur. By relating 

potential energy fluxes to biodensity the potential biomarker fluxes can be calculated and 

their potential release into the atmosphere estimated. 
Since then, a number of scientific discoveries have changed our thinking about Mars. For example, 

the MER rovers have found incontrovertible evidence that water once flowed on the surface of Mars. 

These recent data refute the theory that the fluvial-appearing features on Mars are caused by liquid 

CO2. In addition, there is very recent evidence that the surface of Mars is very active. For example, 

before and after pictures of gullies on Mars suggests that outflows of liquid water occur today. We 

now know that Mars is currently in an interglacial period with ground ice thawing and producing 

recent landslides and debris aprons. We have discovered warm spots on the Martian surface that are 

related to deep open volcanic conduits that undoubtedly have still deeper lava tubes. We have carried 

out ground penetrating radar from orbit to map the ice caps, but have failed to detect distinct subsurface reflectors that may be related to subsurface permafrost brines. We have discovered methane in 

the Martian atmosphere, which could be a biomarker of subsurface life on Mars.

Recent work in astrobiology has shown that microbial activity occurs even at extremely cold temperatures and can live in very extreme environments. Recently microbiologists have discovered 

ultra-small, saline tolerant microbes in 120 kyr Greenland ice and have reported microbial life 

growing at –15 °C and apparently synthesizing amino acids at –80 °C. We have found that chemolithotrophic microbial communities are prolific, complex in permafrost cave environments, and 

can exist in extreme environments such as pH 10 fracture water in ultramafic rock. Microbiologists using environmental chambers simulating Martian environments have found that microorganisms, in particular methanogens, can survive Martian conditions if protected from UV. Recently 

scientists have speculated that life forms could exist in a very oxidizing environment based on a 

hydrogen peroxide water cycle (carbon dioxide plus water producing formaldehyde and hydrogen 

peroxide). Microrganisms based on this chemistry would be sensitive to hyperhydration—death 

by exposure to water.

All of these recent discoveries suggest that life could exist in the shallow subsurface of Mars, and 

that to find life on Mars may not require drilling to great depths to tap the brine beneath the permafrost. Based upon this new information and the concept of biological biomes, figure 1 subdivides 

the Martian crust into potential habitats. 

Any drilling that will be carried out on the surface of Mars will have to be done within the guidelines of planetary protection. Catharine Conley, NASA’s Planetary Protection Officer, presented 

the current planetary protection policy. The two key objectives are to avoid forward contamination 

to preserve planetary conditions for future biological and organic constituent exploration, and to 

avoid backward contamination to protect Earth and its biosphere from potential extraterrestrial 

sources of contamination. Five mission categories have been designated based on mission type 

and planet priorities depending on the astrobiological interest in the target and the probability of 

forward contamination. For example, an Earth-Return mission from any solar system body would 

rate as mission category V due to the potential for backward contamination. For missions with 

lander systems carrying instruments to investigate extant Martian life, the entire landed system 

must be sterilized to levels driven by the nature and sensitivity of the particular life-detection 

experiments, or to limits imposed by planetary restriction regulations, whichever is more stringent. 

Alternatively, only subsystems involved in the acquisition, delivery, and analysis of samples need 

to be sterilized, if methods for preventing recontamination of the sterilized systems and material 

are in place.
Dr. Conley described the new Committee on Space Research (COSPAR) policy that designates 

special regions on Mars. A Special Region is defined as either a region within which terrestrial 

organisms are likely to replicate or a region that has a high potential for the existence of extant 

Martian life. This translates into areas or volumes within which sufficient water activity and sufficiently warm temperatures permit replication of Earth-like organisms. Specifically, the limits on 

water activity are between 0.5 and 1.0. The lower limit for temperature is –25 °C with no upper 

limit. The timescale within which limits can be identified is 500 years. This means that observed 

features for which there is a significant probability of association with liquid water, e.g., gullies, 

pasted-on terrains, and the subsurface, are classified as Special Regions. In the future other Special 

Regions may be created based on geothermal activity, spacecraft induced activity, or the inference 

of possible Martian life forms.

Finally, the constraints that planetary protection requirements place on drilling on the Martian 

surface were discussed. Deep drills (below 5 m) will be accessing Special Regions and therefore 

must be cleaned (and re-cleaned) to levels deemed appropriate for landers (currently <0.3 spores 

per meter2). She ended by describing how this could work on the surface with a combination of 

robotic and human presence. Some regions would be determined to be safe zones from precursor 

missions. The habitats and laboratories would be established in safe zones. Other sites that would 

be characterized as Special Regions would be subject to more stringent sterilization constraints, 

depending on characterization from ground data and remote sensing. One of the key conclusions 

from her presentation is that drilling can proceed on Mars, but the drills will require sterilization 

to meet the requirements for Special Regions. This can be affordably done as, for example, with 

Viking, but it is a cost that needs to be factored into total mission cost.

Peter Doran presented a paper entitled “Drilling as a Science Driver for Human Exploration.” He 

described the results of a study performed by the Human Exploration of Mars Science Analysis 

Group (HEM-SAG) in March 2007. Their charter was to develop the goals and objectives for the 

scientific exploration of Mars by humans. The main assumptions were that there would be three 

missions beginning as early as 2030, that scientific objectives will be set about 5 years prior to 

launch, and that robotic exploration will operate continuously until human missions begin. The 

HEM-SAG concluded that three independent sites is preferable to revisiting the same site, that a 

“long-stay” (~500 days) is preferable to a “short stay” (~30 days), and that human mobility needed 

to be at least 200 km. They also determined the vertical subsurface access (drilling) to be ~300 m 

for access to potential subsurface liquid water zones, less (5–50 m) at multiple sites on traverses. 

Finally, selective recoverable coring, e.g., on polar ice, would be needed for depths from 300 m to 

2 km. Two advantages of human presence was the ability to do lab work on site and the possibility 

of drilling deep into the subsurface.

Deep drilling on Mars would be valuable for determining the large-scale vertical structure and 

chemical and mineralogical composition of the crust. Sampling ground ice would assess recent 

climate change and water cycling. Deep drilling could provide insight into the nature of crustal 

magnetization, could ground truth remote sensing methods such as ground penetrating radar, and 

could document the tectonic history of the crust. In addition to these geophysical reasons, drilling could provide a baseline chronology of the climate history and provide evidence of extinct or 

extant life. Several examples of interesting places to drill were presented based on recent evidence 

for liquid water near the surface.


A number of issues were identified that will require handling prior to human arrival. For example, deep drilling in the ice caps requires understanding how to drill in dirty ice while meeting 

planetary protection issues. Drilling elsewhere on Mars will require determining the feasibility 

of drilling several hundred meters without fluids within reasonable weight and size limits. Other 

feasibility issues include getting humans and/or robots to drill on steep slopes and making the drill 

sufficiently mobile that it can reach interesting drill sites. Other questions raised by the HEM SAG 

group were what are the limits of robotic drilling, do we have to line the hole, and can astronauts 

drill effectively in EVA suits under planetary protocol restrictions. Therefore, if we need to drill 

deep on Mars to answer the important scientific questions, is human presence required? If so, then 

deep drilling may be a driver for human exploration.

In the workshop, we did discuss some of the questions raised above. However, most of the focus 

of the workshop was what can be done with existing technology to drill on the surface of Mars 

remotely. Where are the best places to drill, how deep do you need to drill, and what are the limits 

of autonomy for not only drilling, but alternatives to drills such as moles?

Dr. Chris McKay discussed two potential missions to Mars, one to the north pole and one to 

the south pole. The purpose of the north-pole mission is to search for evidence of liquid water, 

organics, and preserved organisms in five million year old ice. This would require relatively shallow drilling to a depth of between four to ten meters. For liquid water to survive at the surface 

it requires ice, temperatures greater than zero degrees centigrade, and pressures greater than 

6 millibar. These conditions have been attained in the north polar region at least in the recent past. 

Today the obliquity of Mars is 25 degrees, but five million years ago the obliquity of Mars was 

45 degrees, which produced twice the incident sunlight in the polar summer (see figure 2). 

Figure 2. Today the 

obliquity of Mars is 

25 degrees, but five 

million years ago the 

obliquity of Mars was 

45 degrees, which 

produced twice the 

incident sunlight in 

the polar summer.
Shown above in figure 3 is where Mars five million years ago would have fallen on a plot of temperature versus dryness. At the higher obliquities, the surface temperature could have exceeded 

zero degrees centigrade, thereby permitting water to exist on the surface.

The purpose of the south-pole mission is to search for preserved organisms of life that may have 

existed 3–4 billion years ago when Mars was much warmer. This would require sampling in 

the south polar permafrost to much larger depths, probably 100 m. There is evidence that viable 

bacteria exists in 3.5 million year old permafrost in Siberia. There is evidence for metabolism in 

permafrost down to –15 degrees centigrade. Metabolism appears to be limited mainly by nutrient 

transport, not temperature. Micro-organisms in permafrost at 10 degrees centigrade are inactive, 

not because they are frozen, but because they are starving. Dr. McKay showed several instances 

where bacteria existed under extreme conditions on Earth. These provide analogs for believing that 

evidence for ancient Martian life could be preserved in the south pole ice. One could at least expect 

to find fossils of ancient life on Mars. This would tell us that life once existed on Mars, but would 

not tell us the nature of that life or its relationship to life on Earth. 

Dr. Lyle Whyte from McGill University spoke about permafrost microbial biodiversity and ecology. The research objectives were to expand fundamental knowledge of microbial diversity and 

ecology in unique Canadian arctic ecosystems, to determine the cold temperature limits for life, 

and to explore these extremely cold environments as extraterrestrial analogs. Permafrost is an 

Figure 3. A plot of temperature versus dryness comparing 

Mars five million years ago with Mars today.
example of an extreme cryoenvironment. It consists of an upper active layer (0.5–10 m) where 

the temperature fluctuates with air temperature, a permafrost table, and permafrost below that 

down as far as 1450 m. The environment is characterized by subzero temperature, background 

radiation for geological time scales, low water activity, and extremely low rates of nutrient and 

metabolite transfer.

Dr. Whyte discussed work that was carried out under the Astrobiology Science and Technology 

Instrument Development (ASTID) Mars drill project in 2003 in Eureka, Nunavut. The goals of 

this work were to develop ground ice and permafrost aseptic drilling techniques and to explore 

the microbial biodiversity in this environment. Several cores were drilled down to approximately 

15 m. Although the predominant classes of bacteria found were actinobacterial and proteobacteria, 

there was considerable phylogenetic diversity in the core sample. The permafrost microbial activity was studied at subzero temperatures using CO2 flux as a measure. Culturing bacteria at these 

temperatures required the development of low-temperature growth media. The low-temperature 

limit for microbial growth was observed to be –12 degrees centigrade. On Mars we expect very 

low microbial biomass and extremely low rates of microbial activity. Analysis of the ice core 

samples will, therefore, need the requisite sensitivity. He ended his presentation by talking about 

the cold saline springs microbial communities that are found in these permafrost regions.

The morning session ended with a panel discussion entitled “Why, where and how deep?” The 

panelists included T. C. Onsott, Cassie Conley, Chris McKay, Jim Green, and George Cooper. On 

the question of where to look, it was noted that the best targets for drilling are active sites, such 

as newly formed craters, or places where there is evidence of methane or liquid flow near the 

surface. In these sites, life may be closer to the surface, precluding the need to drill too deeply. 

However, we don’t currently know of any active sites, so that drilling in an old lakebed where 

one expects uniform sediment may be the best alternative. Even so, the drill would need limited 

mobility to avoid rocks. It was also noted that dirty ice is better than pure ice as a host for bacteria. 

Dirty ice would not pose a drilling problem, but ice with embedded rocks would be much more 

difficult to drill.

Another discussion topic was how deep to drill and whether humans needed to be in the loop. It 

was generally agreed that having humans in the loop would be very beneficial, not only because 

of their intelligence, but because they are universal system engineers, and with hammer in hand 

can do many tasks easily that are difficult to automate. Humans may also be important in choosing a good drilling site, if the goal is to drill as deeply as possible without getting stuck. Drilling 

through a basalt block is unproductive. It was also noted that cold is your friend when drilling. 

Drilling quickly could melt the ice around the bit, resulting in jamming of the drill when refreezing occurs. Cold drilling is also better from the standpoint of preserving evidence for life.
III. Architectures for Drilling Missions

In the afternoon of the first day, the workshop changed its focus to drill architectures that are applicable to drilling on the Martian subsurface. Kris Zacny gave the foundational talk that provided an 

outstanding introduction to planetary drilling and an overview of the available drill systems. He 

began his talk by giving a brief history of lunar drills, which were 500 watt, battery powered, and 

human operated rotary percussive drills. Drilling on the lunar surface was difficult, as it required 

two astronauts to remove the drill stem from the hole. The lunar experience showed that drilling on 

another planetary surface is difficult even with humans in the loop. Mars would represent an even 

greater challenge than the moon, because of the far greater geological uncertainty. The difficulty 

on Mars is exacerbated by environmental and physical constraints such as low gravity, pressure 

and temperature, large temperature fluctuations, dust storms, and the presence of water-ice. There 

are technological challenges as well, such as transmission delays of up to 20 minutes (one way) 

and power and mass restrictions on the drill.

Dr. Zacny noted that drilling includes augering, that is, there must be a method of removing the cuttings from the hole. He discussed the principles of drilling such as weight-on-bit, which determines 

the stress exerted on the rock. The weight-on-bit must be sufficient to overcome the compressive 

strength of the rock. As drill bits get dull, higher weight-on-bit is needed to maintain penetration. 

He noted that revolutions per minute (rpm) is proportional to drilling power, core temperature rise, 

and auger throughput, which underscores the importance of efficient augering. Augers generally 

work best when conveying dry, loose granular material over short distances and at high rpm. An 

alternative to augering is to use compressed gasses for cuttings removal, and this has been shown 

to be quite efficient at low Martian atmospheric pressure. Drilling at low temperatures is more 

difficult, because the compressive strength of rock increases with decreasing temperature. He also 

noted the concerns for dry drilling, which include an auger for cuttings removal, higher bit wear, 

and higher core temperature rise.

One issue in drilling on Mars is the loss of ice from the heat generated in penetrating the formation. Since ice is relatively easy to penetrate, heat input will sublime a low fraction of the ice in the 

cuttings. However, for a material like basalt, which is difficult to drill and has low porosity, all of 

the trapped ice (if present) is predicted to sublime. Since adsorbed water on any surfaces tends to 

escape under Mars conditions, the friction of the two sliding surfaces is reduced, making drilling 

more efficient. However, if for some reason (such as drilling into hard rocks at high power levels) 

the drill bit reaches higher temperatures, the overlying surface oxide layers escape increasing the 

friction and, in turn, drilling power. 

As part of his overview, Dr. Zacny discussed the existing options for deep drilling. Drilling methods include drill string systems that produce weight-on-bit by using a heavy lander or ground 

anchoring, and autonomous tethered systems that produce weight-on-bit using borehole anchoring. He overviewed the Johnson Space Center-Baker Hughes and Raytheon-United drills, which 

are wire-line rotary coring drills that acquire 2.5 cm diameter and 10 cm long cores. He discussed 

the JPL gopher drill, which is a wire-line percussive coring drill that acquires 4.5 cm diameter 
10

cores, and the Swales-ATK rotary coring drill that acquires 1–2 cm cores. Also discussed were 

the Honeybee/Ames drills (Drilling Automation for Mars Exploration (DAME) and Mars Analog 

Rio Tinto Experiment (MARTE)) that are autonomous “smart drills.” Most of these drills were 

discussed in more detail in subsequent presentations.

Dr. Simon Auclair discussed a simulated Mars mission carried out at the Flashline Mars Arctic 

Research Station located on the rim of Haughton Crater some 900 miles from the North Pole. This 

four-month mission was carried out as realistically as possible, including living in tight quarters 

and using space suits on the 89 Extra Vehicular Activities (EVAs). The main scientific objective 

was to acquire knowledge of the biology and geology of the permafrost as the Arctic winter-tospring transition occurred. The main technical challenge was penetrating the permafrost. The best 

option for accessing the subsurface was a portable core drilling system, such as a Hilti rotary hammer. In particular, they used the Hilti TE 56-ATC CombiHammer, which had three modes of operation, namely, rotation, hammer, and dual. The alternate drill modes helped prevent getting the drill 

stuck in deep holes. They drilled at a number of sites to a usual depth of 32 cm in the permafrost 

(after removing the top active surface with a shovel). A maximum depth of 1.5 meter was reached 

in a polygonal field, and bringing the core up to the surface proved to be a difficult task. Analysis of 

the samples aims at correlating the variations in microbial activity with soil type, water ice content, 

depth, atmospheric conditions and time. The mission was successful in demonstrating that drilling 

could be successful in a Mars analog with humans in the loop.

Dr. Carol Stoker discussed the 2005 Mars Astrobiology Research and Technology Experiment 

(MARTE) robotic drilling mission to Rio Tinto, Spain. The site is a possible modern analog to 

conditions on Mars that formed jarosite rich deposits at Sinus Meridioni. The coring drill has a 

10 m-depth capability, and a fully automated drilling, sample handling, and life detection capability. It has a down hole inspection system that includes a panoramic microscopic imager and a 

Raman spectrometer that can be deployed after drill removal to inspect the bore hole at depths of 

0 to 25 meters. The drill is also equipped with a robust life detection capability that uses microarray technology to detect microorganisms and their metabolic byproducts. 

What sets MARTE apart from other drills is the degree of autonomy. All of its instrumentation can 

be operated remotely to select samples for biological analysis. Samples from a variety of depths 

can be analyzed for biosignatures. MARTE was able to characterize the geological history of the 

Rio Tinto area. Visible and near-infrared spectra of the cores showed the presence of iron-ores 

goethite (FeOOH) and hematite (Fe2O3). Raman spectral analysis revealed organic carbon at some 

locations in the hole. The life detection experiments show the presence of bacteria at all depths.

In conclusion, the MARTE robotic drilling experiment at Rio Tinto demonstrated autonomous 

drilling and sample handling to six meters in 30 days of operation. Drilling to search for life successfully identified in situ organisms with populations varying with depth. The experimental suite 

of instruments was able to characterize the geology of the drill site including mineral identification 

and the detection of organics. The results show that autonomous robotic drilling to search for life 

is technically feasible.
11

Dr. Robin Bolsey gave a brief overview of hot water drilling. He discussed the Ice Core Drilling 

Services (ICDS) system, which is a 20 liter per minute drill system that uses JP8 fuel to heat the 

water. He showed examples of other larger drill systems, such as the Ice Cube hot water system at 

the south pole that can drill 2,500 m, 60 cm diameter holes. Some stone in the ice layer does not 

prevent drilling, in fact, the hot water approach is fairly tolerant to environmental factors such as 

debris and component size distribution. Hot water drills on Mars would likely be used as hole-only 

access drills with objectives achieved at points along the borehole and/or at the bottom.

Dr. Slawek Tulaczyk discussed the Lake and Ice Stream Subglacial Access Research Drilling (LISSARD) project. This is an integrative study of marine ice sheet stability and subglacial life habitats 

in West Antarctica. He showed that Antarctica is a continent with subglacial lakes and rivers below 

the 2000 meter thick ice sheet (see figure 4). The top level scientific objectives of the project are 

to determine whether subglacial lakes cause or contribute to the instability of the West Antarctic 

ice sheet, and whether subglacial lakes have microbial life activity, and if so, what life forms can 

survive in the dark subglacial ecosystems isolated from the atmosphere. These scientific objectives are not only relevant to potential life under the Martian surface, but to other astrobiologically 

interesting sites like Europa.

Figure 4. Antarctica is a continent with subglacial lakes and rivers below the 2000 meter thick 

ice sheet.
12

Dr. Jim Green discussed the drill requirements, design, performance and difficulties associated 

with the KOCI drill. The goal was to develop a new dirty ice drill that was capable of taking quality cores from the surface to the bed of Beacon Valley Glacier. Tests of the drill were performed 

in the Antarctic Specialty Management Area (ASMA). Access is by helicopter, because the rocky 

terrain prevents the use of sleds. The drill consists of a core barrel and core head, inserted cutters, 

rock coring bits, and a drilling rig. Metrics used for drill performance include core quality and 

maximum drill depth. Some of the problems encountered included vibration, penetration rate, heat, 

gravel layers, and chip transport. This drill would be capable of taking core samples in the polar 

regions of Mars. 

Dr. Brian Glass spoke about the current state-of-the-art in autonomous drilling methodology. 

Intelligent drills are essential because of the light-speed delays to Mars (7–20 minutes one way), 

and the lack of knowledge about the geology at the drill site. He described his current automation 

approach that uses several internal agents with defined roles. These agents include a “quick reflex” 

capability that is implemented with very fast rules or upon exceeding sensor limits. Fuzzy neural 

net agents are used to make decisions under normal operating conditions based on incoming data 

and knowledge of past training examples and known faults. A model-based reasoning module is 

invoked when a novel fault or situation occurs that the two previous agents can’t handle. Finally, 

there is an overall executive agent that weighs input from the neural and model-based agents to 

decide the best course of action.

Dr. Glass discussed two automated deep drills, Mars Analog Research and Technology Experiment 

(MARTE) and Drilling Automation for Mars Exploration (DAME). The DAME drill employs 

a structural mechanics neural network monitoring system to detect faults. The DAME drill is 

autonomously operated by the Model-Based Diagnostic System, which continuously monitors 

the drilling process and the state of the drill. If a fault is detected, it analyzes the possible fault 

candidates and reports back to the DAME Executive. The DAME was field tested extensively at 

Haughton Crater in 2006. A full-scale Mars prototype achieved a total depth of 3.2 meters in ice 

layers and breccia in eight days of drilling. It was also tested at JPL in a variety of materials such 

as brick, granite, sand, and plaster with pebbles. It drilled to a meter autonomously in a mixture of 

these materials without prior knowledge of the composition. DAME has therefore demonstrated 

that drilling operations can be controlled remotely, thus enabling future subsurface access on other 

planets. However, for end-to-end capability, these automated drilling capabilities need to be combined with core retrieval and sample handling. Ideally, this autonomous capability should also be 

demonstrated on other planetary-prototype drill hardware architectures such as wireline, corers, 

and rotary percussive drills.
13

IV. Alternatives to Conventional Drilling

On the morning of the second day, attention was turned to alternatives to drilling for accessing 

the Martian subsurface. Carol Stoker presented the working details of the Mars underground mole 

(MUM), which was developed as a low-mass and low-cost alternative to drilling. The MUM was 

developed under the Mars Instrument Funding program as an instrument that could be incorporated 

on a rover. It uses a Raman spectrometer for the detection of subsurface mineralogy and organics. 

The MUM uses a hammering mechanism for forward and reverse propulsion. The mechanism is 

capable of producing a downward impact force of over 63 Newtons at a rate of about 12 impacts 

a minute. It is capable of reaching depths down to two meters, which is the limit of the tether. An 

attractive feature of the mole is its low power consumption—peak power draw is 10 watts. The 

sample collection mechanism collects an average 7 grams of sample, which is returned to the surface for analysis. All logic and control electronics are at the surface. 

The MUM has been successfully integrated with the K-10 rover and field tested in the Marscape 

outdoor test facility at Ames. The MUM executed a ground penetration sequence, sample retrieval, 

and a mole retrieval sequence, all commanded through a remote computer, but otherwise autonomous. A full system test of MUM was also performed in moist beach sand. In summary, the MUM 

is a low-mass system that is capable of obtaining geochemical samples from a rover platform. It is 

an alternative to a drill for penetrating the Martian regolith, but would not be capable of penetrating rock or rocky ice.

Dr. Andrew Mattioda discussed the Site Characterization and Analysis Penetrometer Systems 

(SCAPS) from a terrestrial viewpoint. The SCAPS system, developed by the Army, Navy, and 

Airforce for environmental site characterization, works by pushing penetrometers into the ground 

at a constant rate at the end of a series of rods. One large advantage of penetrometers is that they 

do not produce cuttings like traditional drilling, thus limiting the potential for cross contamination. 

Another advantage is that the instrumentation and software have been advanced to high TRL levels 

here on Earth by the commercial sector. This technology is capable of providing a three-dimensional map of the subsurface soil and water, along with the distribution of organics, metals, etc. 

Many of the same questions that one asks about the subsurface of Mars are asked here on Earth in 

the field of environmental monitoring. These systems have been scaled to various sizes, incorporated into barges and submersible systems and automated, thus they are an attractive alternative to 

conventional drilling.

Dr. George Cooper presented a paper on the slant/horizontal drilling technique. One can imagine 

many places on Mars where this technique would be advantageous, such as the steep terrain where 

there is very recent evidence for outflows of liquid water in gullies. Horizontal drilling is used 

extensively terrestrially to lay pipe under the surface. Typically compressed air is used to push a 

rod beneath the surface. Issues for deploying this technique on Mars include unknown terrain, target selection, and steering. Since there is a sideways feed force, this could produce unstable footing especially on steep terrain. Friction on the hole wall and hole collapse would be other issues. 

These challenges may make autonomous operation of such a drill quite challenging. With humans 

in the loop, however, this technique might be useful at some locations.
14

Dr. Penny Boston spoke about access to natural subsurface cavities, both robotic and human 

approaches. Extraterrestrial caves are interesting for a variety of reasons. They are windows into 

the subsurface (up to 2 km on Earth), and they are potential havens for subsurface microbial ecosystems and repositories for fossils, climate records, sediments, organics, and other signatures of 

the planet’s history. They are also potential human habitats for use on the Moon and Mars that 

provide shielding from the harsh conditions on the surface, especially ionizing and short wavelength ultraviolet radiation. 

One of her main theses was that caves are important scientific targets for planetary missions. We 

know that lava tubes exist on bodies other than Earth. We suspect that any planet with a surface 

will develop cracks, and cracks provide a foundation for solutional and tectonic caves. Speleogenesis, which is the origin and development of natural caves, could also result from entirely nonEarth mechanisms such as impacts. In general, cave formation mechanisms include solutional, 

phase change (e.g., melting and refreezing), mechanical weathering, tectonic events (faulting and 

fracturing), strain relaxation, bioconstruction (vugs, which are small to medium-sized cavities 

inside rock), and catastrophic events such as impacts.

One of the more exciting possibilities for Mars is trapped lava tube deposits. The lava tubes would 

have formed early while volcanoes were still active. Then during the period when Mars was warm 

and wet, water from rain, condensation, or ground water could have become trapped inside the 

lava tube. As Mars became colder and ice formed on the surface, the lava tubes could become permanent ice cave lakes. In the modern era the tube neck could collapse isolating the lava tube from 

surface conditions. These lava tubes could be an ideal target to find ice particles as well as organics 

and microbes that had been trapped potentially for several billion years. Cave geo-microorganisms 

could be alive, dead, or fossilized, or could manifest as biospeleothems (mineral secondary decorations created or influenced by organisms, primarily microorganisms), biotextures or biominerals. 

She showed a number of examples of caves on Earth that demonstrate the wide variety of mineral 

and biological life forms existing in terrestrial caves.

Dr. Boston contrasted the advantages and disadvantages of robotic versus human approaches to 

finding and exploring caves. For robotic exploration she discussed REMotes, which is a variant 

of hopping microbots. Advantages include expendability, sensing and communication capability, 

agility in rough terrain, simplicity and reliability. Because REMotes are small (~100 mm) and light 

(100 grams), 100s-1000s of units can be deployed for a mission. They are powered by hyperefficient micro-fuel cells. Humans have the ability to adapt methodology for studying caves on Earth 

to other planetary bodies, and experience with biosensitive sites. Clearly, caves on Mars would 

make excellent exploration sites, and efforts to find and characterize them should be done both 

robotically and later with human missions.

Dr. Michael Hecht presented a paper entitled “A practical method to autonomously obtain vertical profiles of biomarkers in ice sheets on Earth and Mars.” The technique employs an open-hole 

design that uses a heated drill on a tether and returns the meltwater to the surface. The thermal drill 

consists of a deployment system, a tether, a pumping system, a heater, and electronics for control, 
15

power, and the sensor subsystems. The drill has been demonstrated to 50 meters in Greenland. This 

technique requires that ice constitute >50% of the drilling medium. MARSIS (a multi-frequency 

synthetic radar altimeter with ground penetration capability instrument) indicates that the north 

polar layered deposits are greater than 98% ice, so this drilling technique would be applicable, and 

given Mars ice temperature and gravity, open boreholes would be stable all the way to the base. 

By determining the D/H ratio as a function of depth, it would be possible to create a climate history. Even on the north polar cap of Mars, the pressure is above the triple point of water, so that the 

ice should melt before sublimating. The drill is capable of drilling in dusty ice, albeit somewhat 

slower. The probability of hitting a rock large enough to cause trouble is extremely remote in the 

north polar layered deposits. In addition, the drill is designed to operate autonomously, so that this 

would be a viable drilling method in regions that were predominantly composed of ice.

Dr. Phil Christensen presented an overview of the Tracing Habitability, Organics, and Resources 

(THOR) Mission. The THOR mission uses a high-velocity impactor to create a crater on the surface and an observer spacecraft containing highly capable infrared (IR) spectrometers and visible 

cameras. It is designed to provide an in situ investigation of the deep (>4 meter) sub-surface. 

Targets include the unexplored mid-latitudes with mantles hypothesized to contain water ice. He 

showed a number of potential targets with the goal of placing the impact site within a 50 km 

ellipse. A key mission objective is to determine the abundance of water in the deep Martian subsurface where ice can be stable. High spectral and spatial resolution spectra from the IR camera on the 

observer spacecraft will provide insight into the abundance and origin of key trace gases such as 

methane, SO2, and CO. Other scientific objectives of the mission include testing models of cyclic 

climatic change and the recent occurrence of liquid water, and the search for organic compounds 

in the habitable zones. The orbital phase objectives of the mission include a study of the evolution 

of materials exposed in the crater and to create a new fresh crater for follow-on Mars orbiter and 

rover missions.

Dr. Christensen showed that the depth of diameter of the crater created by the impact depended on 

the nature of the impact site (wet soil/ dry sand/ ice) and the model used to estimate it. Larger craters 

are predicted if the impact site contains ice. Both models that were used to model the impact crater 

showed that a 450 kg projectile would create a crater greater than 4 meters in all soil conditions.

Dr. Yoseph Bar-Cohen spoke about the ultrasonic/sonic driller/corer (USDC) and the challenges of 

inserting new drilling technology into future missions. Using low axial force, the USDC has been 

demonstrated to produce core samples from rocks that range widely in hardness and also to acquire 

powdered cuttings that are mostly several microns in size. The USDC was equipped with sensors 

on the bit to perform inside the borehole measurements. A thermocouple was integrated into the 

USDC bit to measure the temperature in real-time monitoring during drilling. Also, a USDC bit 

was integrated with a fiberoptic sensor and reflectivity measurements from the surface of a rock 

where measured. The USDC was demonstrated as a rock abrasion tool, rock crusher, as well as 

deep penetrator of regolith. For a rock crusher, its actuator harmonic motion creates a series of low 

frequency impacts that quickly crush the sample into fine powder. The USDC can also be used in 

a rotary hammer system.
16

The USDC has been demonstrated to drill in cold ice at low temperature environment. A gopher 

version of the USDC has been field tested in Lake Vida, Antarctica, to a total depth of 176 cm in 

ice. Several other variations of the USDC were also discussed. The USDC can also be deployed 

robotically. Therefore, an advantage of the concept is its versatility. Nevertheless, as Dr. Bar-Cohen 

pointed out, the ability of new technology to address mission challenges is insufficient for insertion 

as mission hardware. He also noted that because drilling and sampling are critical technologies, 

there is a need for a focused development with established simulation test beds and facilities. 
17

V. Breakout Sessions

In the afternoon, the workshop participants broke into two groups to address possible drilling 

missions. The first group chaired by Chris McKay looked at drilling missions in the near term, 

that is, what could be done today with existing technology. The second group chaired by Penny 

Boston looked at possible drilling missions in the mid (20 years out) and long term. The long-term 

scenario considered the possibility of having humans in the loop. The mission concepts that were 

considered by these two groups are summarized in this section.

GROUP 1: POSSIBLE DRILLING MISSIONS IN THE NEAR TERM (5 YEARS)

The near-term group focused on missions that could be proposed within five years. This required 

the use of technology for subsurface access and instrumentation that had already a high technology readiness level (TRL). They ranked missions into four categories based on cost. In order of 

increasing cost the categories were extra low-cost missions, low-cost add-ons to existing missions, 

Scout missions, and large focused subsurface missions. Missions that have a technology or science 

feed towards Mars Sample Return (MSR), as well as ties to the NASA Exploration program, were 

viewed favorably.

In the extra low-cost mission category were an impactor only concept, an impactor with a sheperding spacecraft (LCROSS model), or landing in a recent 100 meter crater identified by MRO and 

searching for organics in the exposed dirt. The science objectives are to detect deep ice, and to 

sample below the ice or the oxidizing zone (for an equatorial impact) a few meters to search for 

organics. An impact into the deep ice would require an impact mass greater than 500 kg, while an 

impact in the equatorial region to sample below the oxidized zone would require a smaller mass. 

It was felt that an impactor mission could be done today either as a standalone or add-on mission. 

Current technology would be able to hit a predetermined target on the surface, which was timed so 

that the impact could be observed by MRO or MSO.

An additional add-on, low-cost mission category discussed were penetrators based on penetrometer technology. Utilizing the high TRL level instrumentation developed for commercial penetrometers, penetrators could be developed as add-ons to other missions. Penetrators could be 

utilized for the seismic investigations, as well as the detection of subsurface water and organics. 

Such instrumentation, utilized in conjunction with impactor missions such as THOR, could provide information concerning Mars subsurface geology as well as identify organics or water vapor 

dispersed by the impact. 

Proposed Scout missions that were discussed included Tracing Habitability, Organics and Resources 

(THOR) (a proposed impactor to explore mid-latitude regions for underground water), the Phoenix 

Mars Lander (on the way to Mars to dig for buried ice in the north polar ice cap), CHRONOS (a 

proposed mission to thermally drill 10–75 m into the north polar ice cap), and Geophysics network 

missions. Drilling missions within the Scout Mission program would be more compelling with 

new evidence for life or water on Mars and with higher TRL for drills.
18

Large focused subsurface drilling missions are feasible in the near term only if there is some new 

compelling evidence for subsurface life. Scenarios such as Phoenix or MSL find organics in the 

ice. Other events that might motivate a large drilling mission include detection of methane, hot 

vents, or squirting gullies that indicate shallow subsurface aquifers.

This breakout session inspired the writing of a white paper entitled “Low-cost multi-use subsurface access to Mars,” where the low-cost impactor approaches discussed in this breakout session 

are discussed more fully. 

GROUP 2: POSSIBLE DRILLING MISSIONS IN THE MID AND LONG TERM

The second breakout session considered drilling missions that could be accomplished within a 

longer time frame. They considered drilling, but also other mission types that provide access to the 

subsurface. To focus the discussion the following assumptions were made. 

(1) Shallow rock core drilling would be a first target (MSL is getting powder, but bedrock will not

be obtained).

(2) ExoMars is going to a 2-3 m depth. 

(3) Technology improvements, while difficult to scope out, must be included in mid- to long-range

planning scenarios. Technologies at the TRL 3-5 levels may achieve sufficient maturity for

this time frame.

(4) Automation is absolutely critical, especially when drilling through soil that is inhomogeneous.

(5) A drilling depth of 40–50 m would be an ambitious, but achievable goal for a dedicated 

drilling mission. 

(6) Voids (caves or vugs) near the surface are of interest scientifically, but present a significant

challenge for automated drilling. 

A key question is how deep do you need to go. This is, of course, dependent on where you dig 

and what science you are trying to answer. The group discussed the tradeoffs. It was felt that a 

moderate robotic mission could be designed to go to 20–50 m, and more ambitious missions to 

several 100 m. Human missions are thought to be feasible to 250–500 m (HEM-SAG report with a 

~4.5 metric ton payload). The group also discussed the advantages and challenges of drilling from 

within caves. 
19

The group divided potential drilling missions into categories based on cost, mass, and power. General consensus was that a drilling mission would be too ambitious and costly to fit within the New 

Horizons mission category, and that a serious drilling mission could not occur until at least 2015-

2016. On the low-cost side, the group discussed a lakebed mission, primarily to search for physical 

and geochemical life traces in a cored stratigraphic column, and an ice drilling mission that potentially would have a higher scientific return, such as living Martians, preserved organics, climaterelevant dust, and isotopic data. Also discussed was a multi-mission staged approach, whereby the 

first mission would obtain the core and analyze the borehole. A follow-on mission would retrieve 

the cached sample for in situ analysis. A drilling microlander mission concept was proposed that 

could be done for approximately $500 million. This would have a 10 kg payload and could achieve 

depths of a few meters in a particularly significant site, such as a lakebed, ice, canyon wall, or cave. 

Robotic missions to 20–50 m are feasible with improvements in drilling methodology and automation. This could be achieved by a wire line system, but other options exist. 

Some of the technology issues that need to be addressed are the payload mass and power requirements needed to drill and bit wear issues. The group discussed laser drilling, which repeatedly 

evaporates a thin layer of material, as an innovative approach for ice missions. Sonic drilling at 

140 Hz appears to be a promising new technology being pioneered in commercial circles. This 

would be worth trying to develop to a higher TRL.
20
21

VI. DISCUSSION OF RESEARCH PRIORITIES AND FOLLOW-ON ACTIVITIES

Pete Worden in his opening remarks noted that subsurface exploration on Mars is necessary to 

understand astrobiology. He felt that there were near-term opportunities for low-cost missions to 

leverage existing larger exploration missions going on between our European partners and us, e.g., 

impactor missions such as LCROSS that can be done for tens of millions of dollars. In addition, 

the community needs to be positioned to take advantage of a serendipitous discovery, such as the 

observation of water or organics near the surface. The community should also have a prioritized 

list of critical technologies that need to be addressed for future subsurface exploration. In the 

longer term, our research priorities need to be consistent with human exploration and settlement. 

Finally, he noted that we should be sensitive to the three ways that missions gain impetus for 

funding, namely interest generated by science advisory committees, such as the space studies or 

decadal studies board, the congress and the public (advocacy for missions like Pluto Express), and 

the private sector. For example, unused capacity on NASA vehicles and funding from entrepreneurial investors might present unexplored opportunities.

Impactors are one class of missions capable of accessing the subsurface that can be carried out 

for relatively low cost and complexity. The key parameters are the mass, delta-V, and degree of 

precision required to produce useful science. Dr. McKay noted that large mass low-precision targeted impactors would be appropriate for impacts into the polar ice regions. Such a mission could 

help ground truth the Mars Odyssey global observations of the Martian surface. The possibility 

of a mission as a secondary payload and of using mass already in orbit was discussed. This latter 

approach raises issues with rendezvousing and docking. Using a simple impactor is an attractive 

alternative, because the impact and long-term activity of the impact site could be observed with 

current assets in place around Mars such as MRO and Odyssey. A subset of the workshop participants led by Andy Gonzales was commissioned to write a short white paper on the impactor 

concept. Might it be possible to put a relatively inexpensive impactor mission into the queue if the 

schedule for Mars Science Lab (MSL) slips?

The next issue that was discussed was how to position the community to take advantage of a serendipitous event such as the discovery of organics. One problem facing the community was the 

current lack of technology investment in drilling technology. Technology development is still 

vitally needed to produce optimal drilling techniques for the various conditions found on Mars. 

Ways to address this shortcoming were discussed, such as promoting the necessity of sub-surface 

exploration, promoting drilling as an important technology to advisory panels, and leveraging off 

possible technology development done on Earth or for lunar research. It was suggested that we 

should stress the resource nature of drilling and the importance of this technology for permanent 

bases on the Moon or Mars. Dr. Zacny noted that the Canadian Space Agency is still investing in 

drilling technology.
22

The final issue that was discussed was the use of drills in human missions. It was noted that 

training of the astronauts would be essential. The Apollo astronauts had considerable difficulty in 

handling drills on the lunar surface. The question of how to train the astronauts led to the comment that we need to build a culture that uses analog environments and simulations in addition to 

training the astronauts. There is little effort in this area other than what is being done by the Mars 

Society. For example, sites like Devon Island provide a realistic field environment to test equipment, communications, and remote operations. Dr. Boston asked the question whether we could 

generate interest in a Mars simulation space school. Another subset of the workshop participants 

agreed to pursue the feasibility of such a school.
23

Agenda
24
25

List of Participants

Allen, Trinity Trinity.L.Allen@gmail.com

Auclair, Simon simon.auclair@hotmail.com

Bar-Cohen, Yoseph yosi@jpl.nasa.gov

Bicay, Michael michael.d.bicay@nasa.gov

Bolsey, Robin robinb@ssec.wisc.edu

Bonaccorsi, Rosalba rbonaccorsi@mail.arc.nasa.gov

Boston, Penny pboston@nmt.edu

Bramall, Nathan nebramall@gmail.com

Bray, Faustin faustin@sound.photosynthesis.com

Briggs, Geoffrey gbriggs@mail.arc.nasa.gov

Colaprete, Anthony Anthony.Colaprete-1@nasa.gov

Christensen, Phil phil.christensen@asu.edu

Conley, Catharine cconley@mail.arc.nasa.gov

Cooper, George cooper@ce.berkeley.edu

Davila, Alfonso F. afernandez-davila@arc.nasa.gov

Domville, Samantha samdomville@yahoo.com

Doran, Peter pdoran@uic.edu

Fisk, Martin mfisk@coas.oregonstate.edu

Ghafoor, Nadeem Nadeem.Ghafoor@mdacorporation.com

Glass, Brian brian.glass@nasa.gov

Gonzales, Andy agonzales@arc.nasa.gov

Green, Jim jim.green@ssec.wisc.edu

Guerrero, Jose Jose.Guerrero@atk.com

Hecht, Michael michael.h.hecht@jpl.nasa.gov

Heldman, Jen jennifer.l.heldmann@nasa.gov

Karcz, John john.s.karcz@nasa.gov

Langhoff, Stephanie slanghoff@mail.arc.nasa.gov

Lee, Pascal pascal.lee@marsinstitute.net

Lemke, Larry llemke@mail.arc.nasa.gov

Levit, Creon Creon.Levit@nasa.gov

Martin, Gary Gary.L.Martin@nasa.gov

Mattioda, Andrew Andrew.L.Mattioda@nasa.gov

McDonald, Alex amacdonald@riacs.edu

McKay, Chris cmckay@mail.arc.nasa.gov

NAME	 AFFILIATION
26

List of Participants

NAME	 AFFILIATION

Morrison, David David.Morrison@nasa.gov

Onstott, Tullis tullis@Princeton.edu

Pilcher, Carl Carl.B.Pilcher@nasa.gov

Smith, Miles Miles.Smith@jpl.nasa.gov

Stoker, Carol Carol.R.Stoker@nasa.gov

Tranfield, Erin erin.tranfield@nasa.gov

Tulaczyk, Slawek tulaczyk@pmc.ucsc.edu

White, Lyle Lyle.Whyte@mcgill.ca

Wilhelm, Mary Beth mbwilhelm47@yahoo.com

Worden, Pete Simon.P.Worden@nasa.gov

Zacny, Kris zacny@honeybeerobotics.com

Zavalet, Jhony R. Jhony.R.Zavaleta@nasa.gov
27

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07/30/2008

NASA Ames Research Center, Moffett Field, CA 94035-1000

National Aeronautics and Space Administration

Washington D.C. 20546-0001

Stephanie Langhoff

Workshop Report On Deep Mars: 

Accessing The Subsurface Of Mars 

On Near-Term Missions

Stephanie R. Langhoff

The workshop encompassed three major themes. The first theme was the scientific objectives of drilling, which center on the 

search for clues to the existence of past life and to the geological and climate history of Mars. Key questions are where and 

how deep to drill? Planetary protection issues were stressed as an important consideration in the design of any drilling mission. 

Secondly, architectures for drilling missions were discussed, including an overview of most of the current drills in operation that 

would be applicable to drilling on Mars. Considerable emphasis was placed on remote operation and drilling automation technologies. Finally, alternatives to conventional drilling were discussed. These included underground moles, penetrometers, horizontal 

drilling, impactors, and access to the subsurface from subsurface cavities. Considerable discussion centered on the possible Mars 

drilling missions that could be performed in both the near and longer term. The workshop participants concluded that useful science could be obtained today using low-cost impactors, with or without a sheperding spacecraft.

Point of Contact: Stephanie R. Langhoff, Ames Research Center, MS 207-3, Moffett Field, CA 94035-1000

(650) 604-6213, Stephanie.R.Langhoff@nasa.gov

Conference Proceedings

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NASA

(650) 604-6213

03/1-2/2008

Unclassified

A-080002

292487.01.01.02

Drilling on Mars, impactors, penetrometers, moles, missions to penetrate the subsurface of Mars