Mapping of shallow subsurface water local variations at Mars’ moderate latitudes with FREND neutron telescope onboard ExoMars TGO

2020 ◽  
Author(s):  
Alexey Malakhov ◽  
Igor Mitrofanov ◽  
Artem Anikin ◽  
Dmitry Golovin ◽  
Maya Djachkova ◽  
...  
Keyword(s):  
Epithermal Neutron ◽  
Subsurface Water ◽  
Trace Gas ◽  
Water Ice ◽  
Shallow Subsurface ◽  
The Past ◽  
Martian Soil ◽  
Landing Sites ◽  
Fine Resolution ◽  
Geomorphological Features

<p>Fine Resolution Epithermal Neutron Detector, FREND, is an instrument onboard ExoMars’ Trace Gas Orbiter (TGO). It uses neutron measurements to detect hydrogen (and thus water) variations in the shallow subsurface of the Martian soil. Similar experiments have been performed in the past on Mars, but FREND’s main characteristic is its neutron collimator that significantly narrows down the field of view (FOV) to 28° full cone which corresponds to a 60-200 km diameter spot on the surface. This is considerably smaller than the spatial resolution of previous experiments and thus allows us to peek inside local features of hydrogen variations.</p><p>The instrument has been measuring for almost one full Martian year currently so what we present is a result of continuous observations of shallow subsurface water between May 2018 and present. A technique to locate the most prominent local spots, either very “dry” or very “wet”, was developed to analyze the planetary surface from 70° North down to 70° South. It yielded several such local spots of interest that are presented, characterized and associated with particular geomorphological features or/and with the selected landing sites candidates.</p><p>It is known that water or water ice is not stable at the surface of Mars, especially closer to equator, thus locating areas with enhanced subsurface hydrogen or water is of much interest both scientifically and in terms of future exploration. FREND is most sensitive to water in the shallow subsurface of about 1 m deep, which makes such deposits easily accessible and valuable.</p>

Variations of polar CO2 caps during the first Martian year of FREND onboard TGO

2020 ◽  
Author(s):  
Dmitry Golovin ◽  
Igor Mitrofanov ◽  
Artem Anikin ◽  
Maya Djachkova ◽  
Denis Lisov ◽  
...  
Keyword(s):  
Spatial Resolution ◽  
Column Density ◽  
Epithermal Neutron ◽  
Trace Gas ◽  
Permafrost Soil ◽  
Polar Regions ◽  
Shallow Subsurface ◽  
Martian Soil ◽  
Seasonal Deposition ◽  
Fine Resolution

<p>Fine Resolution Epithermal Neutron Detector (FREND) is an instrument onboard ExoMars’ Trace Gas Orbiter (TGO). It uses neutron measurements to detect hydrogen (and thus water) variations in the shallow subsurface of the Martian soil. In case of sub-polar regions, it is quite sensitive to the thickness of seasonal deposition of CO<sub>2</sub>, which it well-sees in neutrons, as “dry” layer on top of the hydrogen-rich polar permafrost soil.</p><p>This presentation is aimed to give a first look at variations of seasonal depositions of Carbone dioxide at winter vs summer seasons on Mars. Similar studies have been performed by neutron instruments earlier, however FREND’s major advantage is its much better spatial resolution: by shielding from the neutron flux coming from off-nadir directions, the instrument’s spatial resolution is improved down to a 60-200 km diameter spot. The orbiter’s inclination is currently 74 deg, so the experiment is capable to observe the rim of the polar permafrost northern and southern regions with seasonal coverages of atmospheric Carbone dioxide over them.</p><p>We re-define and improve the shape of polar CO<sub>2</sub> caps boundaries and the column density of seasonal deposits thanks to improved spatial resolution and present data of FREND’s first Martian year of observations of high Martian latitudes.</p>

Local water-rich areas on Mars found by the FREND neutron telescope onboard ExoMars TGO

2020 ◽  
Author(s):  
Alexey Malakhov ◽  
Igor Mitrofanov ◽  
Maxim Litvak ◽  
Anton Sanin ◽  
Dmitry Golovin ◽  
...  
Keyword(s):  
Water Content ◽  
Spatial Resolution ◽  
Epithermal Neutron ◽  
Trace Gas ◽  
Near Surface ◽  
Water Ice ◽  
Landing Sites ◽  
Very High Spatial Resolution ◽  
Local Water ◽  
Fine Resolution

<p>Fine Resolution Epithermal Neutron Detector (FREND) is an instrument onboard ExoMars' Trace Gas Orbiter. Its measurements of epithermal neutron flux on orbit provide data on hydrogen (and thus, water) content in the 1-m thick near-surface regolith layer. Similar experiments have been performed before, neutron sounding is a well-established technique for estimating water content in the celesital body's soil. FREND's chatacteristic feature is its collimator - a massive body surrounding detectors and narrowing their field of view substantially, thus providing for very high spatial resolution, around 60 to 200 km, depending on measurement conditions. Such spatial resolution allows identifying local water-rich features with relief and other geomorphological features, assess water content in small ellipses of future landing sites.</p> <p>In this study we present latest findings based on FREND data, containing a number of surprisingly "wet" local features in the equatorial band. Water or water ice is not stable at the surface of Mars, in the equatorial regions especially, that is why locating areas with enhanced subsurface hydrogen or water is of much interest both to scientists and for the purpose of planning future exploration missions. </p>

Looking for Non-Polar Shallow Subsurface Water Ice in Preparation for Future Human Exploration of Mars  

2021 ◽  
Author(s):  
German Martinez ◽  
Antonio Segura ◽  
Michael D. Smith ◽  
Erik Fischer ◽  
Nilton O. Renno
Keyword(s):  
Subsurface Water ◽  
Water Ice ◽  
Shallow Subsurface ◽  
Human Exploration

Fine Resolution Epithermal Neutron Detector (FREND) Onboard the ExoMars Trace Gas Orbiter

2018 ◽  
Vol 214 (5) ◽  
Author(s):  
I. Mitrofanov ◽  
A. Malakhov ◽  
B. Bakhtin ◽  
D. Golovin ◽  
A. Kozyrev ◽  
...  
Keyword(s):  
Neutron Detector ◽  
Epithermal Neutron ◽  
Trace Gas ◽  
Fine Resolution

scholarly journals Ring‐Mold Craters on Ceres: Evidence for Shallow Subsurface Water Ice Sources

2018 ◽  
Vol 45 (16) ◽  
pp. 8121-8128 ◽  
Author(s):  
K. Krohn ◽  
A. Neesemann ◽  
R. Jaumann ◽  
K. A. Otto ◽  
K. Stephan ◽  
...  
Keyword(s):  
Subsurface Water ◽  
Water Ice ◽  
Shallow Subsurface

Unfrozen subsurface water on Mars: presence and implications

2003 ◽  
Vol 2 (3) ◽  
pp. 213-216 ◽  
Author(s):  
Diedrich T.F. Möhlmann
Keyword(s):  
Time Scales ◽  
Subsurface Water ◽  
Mineral Surfaces ◽  
Martian Surface ◽  
Geological Time ◽  
Surface Layers ◽  
Near Surface ◽  
Water Ice ◽  
Martian Soil ◽  
Water On Mars

It has been concluded from measurements, recently made by Mars Odyssey experiments, that there is water in the upper few metres of the Martian surface at mid- and equatorial latitudes with regionally high contents of up to about 9 wt%. This Martian subsurface water is shown to be in the form of adsorption (or sorption) water. The adsorptive bond of water molecules is about twice as strong on mineral surfaces compared with on water ice. Therefore, evaporation of adsorption water in porous soil happens on time scales, which exceed those of sublimation of water ice by orders of magnitude. Consequently, sorption water can have survived in the near-surface layers of the Martian soil at mid- and equatorial latitudes over geological time scales, where ice must have been lost by sublimation. Sorption water is unfrozen, i.e. liquid-like, down to temperatures of −40°C and below. It must, at least regionally and temporarily, be an important and not a trace constituent of the upper-surface Martian soil. The presence of liquid-like sorption water on Mars is also discussed in view of exobiological implications.

scholarly journals Ceres’ Ezinu quadrangle: a heavily cratered region with evidence for localized subsurface water ice and the context of Occator crater

Icarus ◽  
2018 ◽  
Vol 316 ◽  
pp. 46-62 ◽  
Author(s):  
Jennifer E.C. Scully ◽  
D.L. Buczkowski ◽  
A. Neesemann ◽  
D.A. Williams ◽  
S.C. Mest ◽  
...  
Keyword(s):  
Subsurface Water ◽  
Water Ice

Surface temperature of Martian regolith with polygonal features: influence of the subsurface water ice

2003 ◽  
Vol 51 (9-10) ◽  
pp. 569-580 ◽  
Author(s):  
Konrad J. Kossacki ◽  
Wojciech J. Markiewicz ◽  
Michael D. Smith
Keyword(s):  
Surface Temperature ◽  
Subsurface Water ◽  
Water Ice ◽  
Martian Regolith

A continuous profile of sea ice and freshwater ice thickness by impulse radar

Polar Record ◽  
1974 ◽  
Vol 17 (106) ◽  
pp. 31-41 ◽  
Author(s):  
K. J. Campbell ◽  
A. S. Orange
Keyword(s):  
Feasibility Study ◽  
Sea Water ◽  
Time Profile ◽  
Ice Thickness ◽  
Water Ice ◽  
Shallow Subsurface ◽  
Impulse System ◽  
Chart Recorder ◽  
Single Trace ◽  
Subbottom Profiling

For several years. Geophysical Survey Systems, Inc has been using an impulse radar system as a shallow subsurface exploration tool for engineering applications. Recently this system has been applied to the measurement of ice thicknesses both on sea-water and fresh-water ice. In the course of a feasibility study performed in December 1972, thebasic operating parameters and limitations of the tool when operated on ice were determined. Following the feasibility study, operational surveys were performed totalling approximately 11 crew-months and covering in excess of 1 500 km of survey route at several locations in the Canadian Arctic. The technique is known as Electromagnetic Subsurface Profiling (ESP), and it can be considered the electromagnetic equivalent of the single-trace acoustic profiling methods used for marine subbottom profiling. In practice, ice-thickness profiling is done by towing a sled-mounted antenna behind a tracked vehicle containing the impulse system (Fig 1). Real-time profile data are displayed graphically on a strip-chart recorder. The data may also be recorded on magnetic tape for later processing and playback.

The ExoMars Trace Gas Orbiter – First Martian Year in Orbit

2020 ◽  
Author(s):  
Håkan Svedhem ◽  
Oleg Korablev ◽  
Igor Mitrofanov ◽  
Daniel Rodionov ◽  
Nicholas Thomas ◽  
...  
Keyword(s):  
Surface Science ◽  
Dust Storm ◽  
European Space Agency ◽  
High Sensitivity ◽  
Global Scale ◽  
Trace Gas ◽  
Full Potential ◽  
Water Ice ◽  
Surface Hydrogen ◽  
Space Agency

<p>The Trace Gas Orbiter, TGO, has in March 2020 concluded its first Martian year in its 400km, 74 degrees inclination, science orbit. It has been a highly successful year, starting with the rise, plateau and decay of the major Global Dust Storm in the summer of 2018. This has enabled interesting results to be derived on the water vapour distribution, dynamic behaviour and upward transport as a consequence of the dust storm. The characterisation of the minor species and trace gasses is continuing and a large number of profiles is produced every day. A dedicated search of methane has shown that there is no methane above an altitude of a few km, with an upper limit established at about 20 ppt (2∙10<sup>-11</sup>). The solar occultation technique used by the spectrometers has definitely proven its strength, both for its high sensitivity and for its capability of making high resolution altitude profiles of the atmosphere. Climatological studies have been initiated and will become more important now that a full year has passed, even if the full potential will be visible only after a few Martian years of operation. The FREND instrument has characterised the hydrogen in the shallow sub-surface on a global scale at a spatial resolution much better than previous missions have been able. It has found areas at surprisingly low latitudes with significant amounts of sub-surface hydrogen, most likely in the form of water ice. The CaSSIS camera has made a high number of images over a large variety of targets, including the landing sites of the 2020 ESA and NASA rovers, Oxia Planum and the Jezero Crater. Stereo imaging has enabled topographic information and precise 3-D landscape synthesis.</p><p>This presentation will summarise the highlights of the first Martian year and discuss planned activities for the near and medium term future.</p><p>The ExoMars programme is a joint activity by the European Space Agency (ESA) and ROSCOSMOS, Russia. It consists of the ExoMars 2016 mission, launched 14 March 2016, with the Trace Gas Orbiter, TGO, and the Entry Descent and Landing Demonstrator, EDM, named Schiaparelli, and the ExoMars 2020 mission, to be launched in July/August 2020, carrying a Rover and a surface science platform to the surface of Mars. <strong><br></strong></p>

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