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The first definitive evidence for continental vents on Mars is the in situ detection of amorphous silica-rich outcrops by the Mars Exploration Rover Spirit. These outcrops have been tentatively interpreted as the result of either acid sulfate leaching in fumarolic environments or direct precipitation from hot springs. Such environments represent prime targets for upcoming astrobiology missions but remain difficult to identify with certainty, especially from orbit. To contribute to the identification of fumaroles and hot spring deposits on Mars, we surveyed their characteristics at the analog site of the Solfatara volcanic crater in central Italy. Several techniques of mineral identification (VNIR spectroscopy, Raman spectroscopy, XRD) were used both in the field and in the laboratory on selected samples. The faulted crater walls showed evidence of acid leaching and alteration into the advanced argillic-alunitic facies, with colorful deposits containing alunite, jarosite, and/or hematite. Sublimates containing various Al and Fe hydroxyl-sulfates were observed around the active fumarole vents at 90°C. One vent at 160°C was characterized by different sublimates enriched in As and Hb sulfide species. Amorphous silica and alunite assemblages that are diagnostic of silicic alteration were also observed at the Fangaia mud pots inside the crater. A wide range of minerals was identified at the 665 m diameter Solfatara crater that is diagnostic of acid-steam heated alteration of a trachytic, porous bedrock. Importantly, this mineral diversity was captured at each site investigated with at least one of the techniques used, which lends confidence for the recognition of similar environments with the next-generation Mars rovers.

The Mars 2020 mission will seek the signs of ancient life on Mars and will identify, prepare, document, and cache a set of samples for possible return to Earth by a follow-on mission. Mars 2020 and its Perseverance rover thus link and further two long-held goals in planetary science: a deep search for evidence of life in a habitable extraterrestrial environment, and the return of martian samples to Earth for analysis in terrestrial laboratories. The Mars 2020 spacecraft is based on the design of the highly successful Mars Science Laboratory and its Curiosity rover, but outfitted with a sophisticated suite of new science instruments. Ground-penetrating radar will illuminate geologic structures in the shallow subsurface, while a multi-faceted weather station will document martian environmental conditions. Several instruments can be used individually or in tandem to map the color, texture, chemistry, and mineralogy of rocks and regolith at the meter scale and at the submillimeter scale. The science instruments will be used to interpret the geology of the landing site, to identify habitable paleoenvironments, to seek ancient textural, elemental, mineralogical and organic biosignatures, and to locate and characterize the most promising samples for Earth return. Once selected, ∼35 samples of rock and regolith weighing about 15 grams each will be drilled directly into ultraclean and sterile sample tubes. Perseverance will also collect blank sample tubes to monitor the evolving rover contamination environment. In addition to its scientific instruments, Perseverance hosts technology demonstrations designed to facilitate future Mars exploration. These include a device to generate oxygen gas by electrolytic decomposition of atmospheric carbon dioxide, and a small helicopter to assess performance of a rotorcraft in the thin martian atmosphere. Mars 2020 entry, descent, and landing (EDL) will use the same approach that successfully delivered Curiosity to the martian surface, but with several new features that enable the spacecraft to land at previously inaccessible landing sites. A suite of cameras and a microphone will for the first time capture the sights and sounds of EDL. Mars 2020’s landing site was chosen to maximize scientific return of the mission for astrobiology and sample return. Several billion years ago Jezero crater held a 40 km diameter, few hundred-meter-deep lake, with both an inflow and an outflow channel. A prominent delta, fine-grained lacustrine sediments, and carbonate-bearing rocks offer attractive targets for habitability and for biosignature preservation potential. In addition, a possible volcanic unit in the crater and impact megabreccia in the crater rim, along with fluvially-deposited clasts derived from the large and lithologically diverse headwaters terrain, contribute substantially to the science value of the sample cache for investigations of the history of Mars and the Solar System. Even greater diversity, including very ancient aqueously altered rocks, is accessible in a notional rover traverse that ascends out of Jezero crater and explores the surrounding Nili Planum. Mars 2020 is conceived as the first element of a multi-mission Mars Sample Return campaign. After Mars 2020 has cached the samples, a follow-on mission consisting of a fetch rover and a rocket could retrieve and package them, and then launch the package into orbit. A third mission could capture the orbiting package and return it to Earth. To facilitate the sample handoff, Perseverance could deposit its collection of filled sample tubes in one or more locations, called depots, on the planet’s surface. Alternatively, if Perseverance remains functional, it could carry some or all the samples directly to the retrieval spacecraft. The Mars 2020 mission and its Perseverance rover launched from the Eastern Range at Cape Canaveral Air Force Station, Florida, on July 30, 2020. Landing at Jezero Crater will occur on Feb 18, 2021 at about 12:30 PM Pacific Time.

Geologists in the field climb hills and hang onto craggy outcrops; they put their fingers in sand and scratch, smell, and even taste rocks. Beginning in 2004, however, a team of geologists and other planetary scientists did field science in a dark room in Pasadena, exploring Mars from NASA's Jet Propulsion Laboratory (JPL) by means of the remotely operated Mars Exploration Rovers (MER). Clustered around monitors, living on Mars time, painstakingly plotting each movement of the rovers and their tools, sensors, and cameras, these scientists reported that they felt as if they were on Mars themselves, doing field science. The MER created a virtual experience of being on Mars. In this book, William Clancey examines how the MER has changed the nature of planetary field science. NASA cast the rovers, Spirit and Opportunity, as \"robotic geologists,\" and ascribed machine initiative (\"Spirit collected additional imagery...\") to remotely controlled actions. Clancey argues that the actual explorers were not the rovers but the scientists, who imaginatively projected themselves into the body of the machine to conduct the first overland expedition of another planet. The scientists have since left the darkened room and work from different home bases, but the rover-enabled exploration of Mars continues. Drawing on his extensive observations of scientists in the field and at the JPL, Clancey investigates how the design of the rover mission enables field science on Mars, explaining how the scientists and rover engineers manipulate the vehicle and why the programmable tools and analytic instruments work so well for them. He shows how the scientists felt not as if they were issuing commands to a machine but rather as if they were working on the red planet, riding together in the rover on a voyage of discovery. http://www.youtube.com/watch?v=oZQSWSZnTYs&feature=youtube_gdata

Explore a whole new world! Could Mars be a future home for humans? Were there ever aliens on the red planet? How does Mars compare to our own planet? Discover the answer to these questions, and more, with The Story of Mars. The Story of Mars takes a fascinating look at the history, geography, astronomy and science of the red planet. For ages 9+.

The Ingenuity Helicopter will be deployed from the Perseverance Rover for a 30-sol experimental campaign shortly after the rover lands and is commissioned. We describe the helicopter and the associated Technology Demonstration experiment it will conduct, as well as its role in informing future helicopter missions to Mars. This helicopter will demonstrate, for the first time, autonomous controlled flight of an aircraft in the Mars environment, thus opening up an aerial dimension to Mars exploration. The 1.8 kg , 1.2 m diameter helicopter, with twin rotors in a counter-rotating co-axial configuration, will help validate aerodynamics, control, navigation and operations concepts for flight in the thin Martian atmosphere. The rover supports a radio link between the helicopter and mission operators on Earth, and information returned from a planned set of five flights, each lasting up to 90 seconds, will inform the development of new Mars helicopter designs for future missions. Such designs in the 4 kg – 30 kg range would have the capability to fly many kilometers daily and carry science payloads of 1 kg – 5 kg . Small helicopters can be deployed as scouts for future rovers helping to select interesting science targets, determine optimal rover driving routes, and providing contextual high-vantage imagery. Larger craft can be operated in standalone fashion with a tailored complement of science instruments with direct-to-orbiter communication enabling wide-area operations. Other roles including working cooperatively with a central lander to provide area-wide sampling and science investigations. For future human exploration at Mars, helicopter can be employed to provide reconnaissance.

This book introduces the reader to the wonders of Mars, covering all aspects from our past perceptions of the planet through to the latest knowledge on its history, its surface processes such as impact cratering, volcano formation, and glaciation, and its atmosphere and climate. In addition, a series of ten intriguing open issues are considered in a more advanced way. These include such thought-provoking questions as What turned off the planet's magnetic field?, Why are the northern and southern hemispheres so different?, What was the fate of the once abundant water?, and Is there, or was there, life on Mars? Numerous original figures, unavailable elsewhere, reproduce details of images from Viking, CTX, MOC, HiRISE, THEMIS, and HRSC.

The active hot springs, fumaroles, and mud pots of the southwestern Lassen hydrothermal system include various alteration environments, which produce a range of hydrothermal mineral assemblages. Analysis of water, mineral precipitates, altered sediment, and rock samples collected at and near these features at Sulphur Works, Bumpass Hell, Little Hot Springs Valley, and Growler and Morgan Hot Springs reveals conditions ranging from ∼100 °C acid-sulfate fumaroles (e.g., Sulphur Works and Bumpass Hell) to near-neutral hot springs (e.g., Growler and Morgan), and includes both oxidizing and reducing conditions. Resulting hydrothermal minerals include a wide variety of sulfates (dominated by Al-sulfates, but also including Fe2+, Fe3+, Ca, Mg, and mixed-cation sulfates), sulfides (pyrite and marcasite), elemental sulfur, and smectite and kaolinite clays. Most altered samples contain at least one silica phase, most commonly quartz, but also including cristobalite, tridymite, and/or amorphous silica. Quartz and other silica phases are not as abundant in the less altered rock samples, thus their abundance in some hydrothermally altered sediment samples suggests a detrital origin, or formation by hydrothermal alteration (either modern or Pleistocene); this requires a high degree of diagenetic (or epigenetic) maturation. These results support a previously identified model that the Lassen hydrothermal system involves the de-coupling of a vapor phase (which becomes acidic as it oxidizes near the surface, producing acid-sulfate fumaroles at higher elevations at Sulphur Works and Bumpass Hell) from the residual near neutral thermal waters that emerge as hot springs at lower elevations (Growler and Morgan). Because both acid-sulfate fumarole and near-neutral sinter-producing hot springs have been invoked to explain the silica-rich deposits observed by the Mars Exploration Rover Spirit near Home Plate in the Columbia Hills on Mars, Lassen can serve as a useful terrestrial analog for comparison.