H2O at the Phoenix landing site.
نویسندگان
چکیده
The Phoenix mission investigated patterned ground and weather in the northern arctic region of Mars for 5 months starting 25 May 2008 (solar longitude between 76.5 degrees and 148 degrees ). A shallow ice table was uncovered by the robotic arm in the center and edge of a nearby polygon at depths of 5 to 18 centimeters. In late summer, snowfall and frost blanketed the surface at night; H(2)O ice and vapor constantly interacted with the soil. The soil was alkaline (pH = 7.7) and contained CaCO(3), aqueous minerals, and salts up to several weight percent in the indurated surface soil. Their formation likely required the presence of water.
منابع مشابه
Geologic Setting and Surface Properties of the Mars Phoenix Landing
Introduction: The Phoenix Lander touched down just before the northern summer solstice at 68.22 N, 234.25 E (areocentric) and operated for 152 sols. The lander is located on patterned ground superimposed on ejecta deposits from the nearby bowl-shaped 10 km Heimdall crater. The robotic arm was able to excavate a dozen trenches on polygon centers, edges, and troughs, exposing and sampling a thin ...
متن کاملStability of perchlorate hydrates and their liquid solutions at the Phoenix landing site, Mars
[1] We studied the low-temperature properties of sodium and magnesium perchlorate solutions as potential liquid brines at the Phoenix landing site. We determined their theoretical eutectic values to be 236 ± 1 K for 52 wt% sodium perchlorate and 206 ± 1 K for 44.0 wt% magnesium perchlorate. Evaporation rates of solutions at various concentrations were measured under martian conditions, and rang...
متن کاملCold and dry processes in the Martian Arctic: Geomorphic observations at the Phoenix landing site and comparisons with terrestrial cold desert landforms
[1] We analyze Surface Stereo Imager observations of rocks, sediments, and permafrost-related landforms in the vicinity of the Phoenix lander, comparing the imaged features to analogous examples of physical weathering and periglacial processes observed in the Antarctic Dry Valleys. Observations at the Phoenix landing site of pitted rocks, ‘‘puzzle rocks’’ undergoing in-situ breakdown, perched c...
متن کاملProposed Research Plan Perchlorate Salt Effect on Rock Weathering on Mars at Phoenix Landing Site
The Phoenix Mission was the first to land in the polar regions on Mars. The mission revealed three surprising results: (1) The surface at the landing site had a very low concentration of large size rocks, (2) The unexpectedly sticky nature of the soil prevented it initially from falling through one of the instrument’s screens as planned, (3) Perchlorate salt was found at a high concentration (~...
متن کاملPerchlorate Salt Effects on Rock Weathering on Mars at the Phoenix Landing Site
Statement of the problem: The Phoenix Mission was the first to land in the polar regions on Mars. The mission revealed three surprising results: (1) The surface at the landing site had a very low concentration of large size rocks, (2) The unexpectedly sticky nature of the soil prevented it initially from falling through one of the instrument’s screens as planned, (3) Perchlorate salt was found ...
متن کاملMechanistic Studies on the Radiolytic Decomposition of Perchlorates on the Martian Surface
Perchlorates—inorganic compounds carrying the perchlorate ion (ClO4)—were discovered at the north polar landing site of the Phoenix spacecraft and at the southern equatorial landing site of the Curiosity Rover within the Martian soil at levels of 0.4–0.6 wt%. This study explores in laboratory experiments the temperature-dependent decomposition mechanisms of hydrated perchlorates—namely magnesiu...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Science
دوره 325 5936 شماره
صفحات -
تاریخ انتشار 2009