Data Needed to Get Humans to and Keep Them Alive Panel

Richard (Rick) Davis Moderator @RedPlanetRick NASA HQ Panelists: Nathaniel (Than) Putzig Ice Deposits/Water Mapping [email protected] Planetary Science Institute Gareth Morgan Ice Deposits/Water Mapping [email protected] Planetary Science Institute Zachary Mank In-Situ Resource Utilization [email protected] Honeybee Robotics Fred Calef Landing Site/Hazard Maps @cirquelar / Fred.Calef@jpl..gov NASA JPL Laura Fackrell Agriculture [email protected] University of Georgia 180º E CURRENT STATE of KNOWLEDGE

• Integrating multiple datasets is a fruitful means to generate ice mapping products (see: swim.psi.edu)

• Ultimately we are limited by the parameters of current/past orbital assets.

• Difficult to reconcile wide spread ice 270º E abundance and structure between 1 – 15 m into the subsurface.

• There is a strong case for the need for new orbital instruments, especially a 60º N SAR/high frequency Sounder combo - please see NEX-SAG report

30º N IMPORTANT LESSIONS from COMPARITIVE PLANETOLOGY

• Terrestrial analogsare of course paramount to searching for ice on Mars and developing/testing technology to extract that ice

• However, we shouldn’t discount lessons learned from our air-less, yet icy neighbors:

MERCURY The Moon

North Pole of Mercury. Yellow High S-band SC return. Background Image from MESSENGER IMPORTANT LESSIONS from COMPARITIVE PLANETOLOGY

The MOON

Earth-based Image Orbital Monostatic SAR Bistatic SAR

Arecibo

Mini - RF

Patterson et al. [2017] IMPORTANT LESSIONS from COMPARITIVE PLANETOLOGY

The MOON

Earth-based Image radar Orbital Monostatic SAR Bistatic SAR

Modelled after Hapke et al. [2012] and Hapke and Blew ett [1991]

Neish et al., 2011

Campbell and Campbell 2006

Patterson et al. [2017] THE ELEPHANT IN THE ROOM IS THERE ACCESSIBLE WATER ICE?

• Neutron and thermal spectrometers detect ice shallower than ~1 m while SHARAD detects ice interfaces deeper than ~15 m. There is no current capability at Mars to reliably detect the top of ice between 1 and 15 m depth.

• and ExoMars rovers will have ground- penetrating (GPRs) purportedly capable of detecting ice in this zone -- but they are not going to locations likely to contain ice. RIMFAX • NEX-SAG, ICE-SAG: A top priority for new Mars orbiters is radars capable of detecting ice in this zone. FLY IN THE OINTMENT WILL NEW RADARS ACTUALLY DO THE TRICK?

• Terrestrial GPRs are often limited to a couple meters depth (largely in wet soils).

• SHARAD detects basal interfaces of ice in a few areas, but vast regions – in and out of MONS- detected ice zones – have no SHARAD returns.

• This lack of widespread SHARAD returns may be due to severe attenuation of the radar signal by iron oxides or hydrated minerals [e.g., Stillman and Grimm, 2011]. B2 Stealth Bomber (Image credit: www.defense.gov) A SOUND ALTERNATIVE ACTIVE-SOURCE SEISMIC METHODS Seismic methods use acoustic waves, which are not subject to the same scattering and attenuation considerations of radar. A fixed or mobile source combined with one or more mobile receivers can map out a profile or volume of subsurface data. The offset between elements enables analysis of subsurface properties.

Courville et al. [2018] PRELIMINARY ANALYSIS SENIOR DESIGN WORK BY SAM COURVILLE (CSM, 2017) 2-D cross section for a potential target scenario. This geologic model presents a case where SHARAD would likely be unable to differentiate the top and bottom of a thin ice layer.

Simulated seismic data from model with source at x=0. Traces running parallel to the travel-time (t) axis show amplitudes of reflected seismic waves at each receiver location.

Image created from simulated data. Subsurface reflectors correspond to layer bounds within the model above.

Thank You! Any Questions?

Richard (Rick) Davis Moderator @RedPlanetRick NASA HQ Panelists: Nathaniel (Than) Putzig Ice Deposits/Water Mapping [email protected] Planetary Science Institute Gareth Morgan Ice Deposits/Water Mapping [email protected] Planetary Science Institute Zachary Mank In-Situ Resource Utilization [email protected] Honeybee Robotics Fred Calef Landing Site/Hazard Maps @cirquelar / [email protected] NASA JPL Laura Fackrell Martian Agriculture [email protected] University of Georgia