Antarctic lakes (above and beneath the ice sheet): Analogues for Mars

The perennial ice covered lakes of the Antarctic are considered to be excellent analogues to lakes that once existed on Mars. Field studies of ice covered lakes, paleolakes, and polar beaches were conducted in the Bunger Hills Oasis, Eastern Antarctica. These studies are extended to the Dry Valleys, Western Antarctica, and the Arctic. Important distinctions were made between ice covered and non-ice covered bodies of water in terms of the geomorphic signatures produced. The most notable landforms produced by ice covered lakes are ice shoved ridges. These features form discrete segmented ramparts of boulders and sediments pushed up along the shores of lakes and/or seas. Sub-ice lakes have been discovered under the Antarctic ice sheet using radio echo sounding. These lakes occur in regions of low surface slope, low surface accumulations, and low ice velocity, and occupy bedrock hollows. The presence of sub-ice lakes below the Martian polar caps is possible. The discovery of the Antarctic sub-ice lakes raises possibilities concerning Martian lakes and exobiology

The Martian valley networks: Origin by niveo-fluvial processes

The valley networks may hold the key to unlocking the paleoclimatic history of Mars. These enigmatic landforms may be regarded as the Martian equivalent of the Rosetta Stone. Therefore, a more thorough understanding of their origin and evolution is required. However, there is still no consensus among investigators regarding the formation (runoff vs. sapping) of these features. Recent climatic modeling precludes warm (0 degrees C) globally averaged surface temperatures prior to 2 b.y. when solar luminosity was 25-30 percent less than present levels. This paper advocates snowmelt as the dominant process responsible for the formation of the dendritic valley networks. Evidence for Martian snowfall and subsequent melt has been discussed in previous studies

Research Study for Determination of Liquid Surface Profile in a Cryogenic Tank During Gas Injection Annual Report, 18 Jun. 1967 - 17 Jun. 1968

Determining entrainment of entrapped liquid as function of air flow, and viscosit

Research Study for Determination of Liquid Surface Profile in a Cryogenic Tank During Gas Injection Quarterly Report, 18 Dec. 1967 - 17 Mar. 1968

Correlation equation on entrainment-viscosity behavior in cryogenic tank during gas injectio

Martian deltas: Morphology and distribution

Recent detailed mapping has revealed numerous examples of Martian deltas. The location and morphology of these deltas are described. Factors that contribute to delta morphology are river regime, coastal processes, structural stability, and climate. The largest delta systems on Mars are located near the mouths of Maja, Maumee, Vedra, Ma'adim, Kasei, and Brazos Valles. There are also several smaller-scale deltas emplaced near channel mouths situated in Ismenius Lacus, Memnonia, and Arabia. Delta morphology was used to reconstruct type, quantity, and sediment load size transported by the debouching channel systems. Methods initially developed for terrestrial systems were used to gain information on the relationships between Martian delta morphology, river regime, and coastal processes

Research study for determination of liquid surface profile in a cryogenic tank during gas injection Quarterly progress report, 18 Sep. - 18 Dec. 1967

Liquid surface profile determination in cryogenic tank during gas injectio

Mars Pathfinder Landing Site Workshop 2: Characteristics of the Ares Vallis Region and Field Trips in the Channeled Scabland, Washington

Mars Pathfinder will place a single lander on the surface of Mars on July 4, 1997, following a December 1996 launch. As a result of the very successful first Mars Pathfinder Landing Site Workshop, the project has selected the Ares Vallis outflow channel in Chryse Planitia as the landing site. This location is where a large catastrophic outflow channel debouches into the northern lowlands. A second workshop and series of field trips, entitled Mars Pathfinder Landing Site Workshop 2: Characteristics of the Ares Vallis Region and Field Trips in the Channeled Scabland, Washington, were held in Spokane and Moses Lake, Washington. The purpose of the workshop was to provide a focus for learning as much as possible about the Ares Vallis region on Mars before landing there. The rationale is that the more that can be learned about the general area prior to landing, the better scientists will be able interpret the observations made by the lander and rover and place them in the proper geologic context. The field trip included overflights and surface investigations of the Channeled Scabland (an Earth analog for the martian catastrophic outflow channels), focusing on areas particularly analogous to Ares Vallis and the landing site. The overflights were essential for placing the enormous erosional and depositional features of the Channeled Scabland into proper three-dimensional context. The field trips were a joint educational outreach activity involving K-12 science educators, Mars Pathfinder scientists and engineers, and interested scientists from the Mars scientific community. Part 1 of the technical report on this workshop includes a description of the Mars Pathfinder mission, abstracts accepted for presentation at the workshop, an introduction to the Channeled Scabland, and field trip guides for the overflight and two field trips. This part, Part 2, includes the program for the workshop, summaries of the workshop technical sessions, a summary of the field trips and ensuing discussions, late abstracts of workshop presentations, reports on the education and public outreach activities carried out by the educators, and a list of the workshop and field trip participants

Lessons Learned for Geologic Data Collection and Sampling: Insights from the Desert RATS 2010 Geologist Crewmembers

Since 1997, Desert Research and Technology Studies (D-RATS) has conducted hardware and operations tests in the Arizona desert that advance human and robotic planetary exploration capabilities. D-RATS 2010 (8/31-9/13) simulated geologic traverses through a terrain of cinder cones, lava flows, and underlying sedimentary units using a pair of crewed rovers and extravehicular activities (EVAs) for geologic fieldwork. There were two sets of crews, each consisting of an engineer/commander and an experienced field geologist drawn from the academic community. A major objective of D-RATS was to examine the functions of a science support team, the roles of geologist crewmembers, and protocols, tools, and technologies needed for effective data collection and sample documentation. Solutions to these problems must consider how terrestrial field geology must be adapted to geologic fieldwork during EVA

Conducting Planetary Field Geology on EVA: Lessons from the 2010 DRATS Geologist Crewmembers

In order to prepare for the next phase of planetary surface exploration, the Desert Research and Technology Studies (DRATS) field program seeks to test the next generation of technology needed to explore other surfaces. The 2010 DRATS 14-day field campaign focused on the simultaneous operation of two habitatable rovers, or Space Exploration Vehicles (SEVs). Each rover was crewed by one astronaut/commander and one geologist, with a change in crews on day seven of the mission. This shift change allowed for eight crew members to test the DRATS technology and operational protocols [1,2]. The insights presented in this abstract represent the crew s thoughts on lessons learned from this field season, as well as potential future testing concepts

Desert Rats 2010 Operations Tests: Insights from the Geology Crew Members

Desert Research and Technology Studies (Desert RATS) is a multi-year series of tests of NASA hardware and operations deployed in the high desert of Arizona. Conducted annually since 1997, these activities exercise planetary surface hardware and operations in relatively harsh conditions where long-distance, multi-day roving is achievable. Such activities not only test vehicle subsystems, they also stress communications and operations systems and enable testing of science operations approaches that advance human and robotic surface exploration capabilities. Desert RATS 2010 tested two crewed rovers designed as first-generation prototypes of small pressurized vehicles, consistent with exploration architecture designs. Each rover provided the internal volume necessary for crewmembers to live and work for periods up to 14 days, as well as allowing for extravehicular activities (EVAs) through the use of rear-mounted suit ports. The 2010 test was designed to simulate geologic science traverses over a 14-day period through a volcanic field that is analogous to volcanic terrains observed throughout the Solar System. The test was conducted between 31 August and 13 September 2010. Two crewmembers lived in and operated each rover for a week with a "shift change" on day 7, resulting in a total of eight test subjects for the two-week period. Each crew consisted of an engineer/commander and an experienced field geologist. Three of the engineer/commanders were experienced astronauts with at least one Space Shuttle flight. The field geologists were drawn from the scientific community, based on funded and published field expertise