# Presentation: 497678

## CRISM (Compact Reconnaissance Imaging Spectrometer for Mars) on MRO 

## Outline

**Team**
**Investigation strategy**
**Instrument overview**
**Instrument performance**
**Data and data products**

## CRISM Team

## OMEGA and CRISM: A 2-stage VISIR spectral investigation of Mars

**Variations mafic mineralogy of Syrtis Major Region**

**OMEGA is revealing unexpected diversity**
**Variations in px composition, new ol-rich areas**
**Concentrations of hydrated minerals (sulfates, clays)**
**Mapping / grain size determination of CO****2**** and H****2****O components of polar caps**
**However...**
**Spatial resolution is ~1 km**
**Observations nearly all nadir, so surface / atmosphere separation model-dependent**
**CRISM will build on OMEGA with**
**>20x greater spatial resolution**
**2x greater spectral resolution**
**Extensive measurements to separate the surface and atmosphere**

## CRISM Objective 1: Find deposits of interest up to 5 times smaller

**OMEGA (300-1000 m/pixel,13 nm/ch.): discovers large deposits**

**CRISM multispectral survey (100- 200 m/pix, 72 ch.):  discovers small deposits**

** ****CRISM targeted hyperspectral        (15-38 m/pixel, 6.55 nm/ch): characterizes deposits**

**OMEGA is discovering deposits of interest kilometers in size**
**CRISM’s multispectral survey will discover deposits to ~200 m size**
**CRISM will characterize these targets hyperspectrally at 15-38 m/pixel**

*** Proof of concept using resampled AVIRIS data**

## CRISM Objective 2: Separate the Surface and Atmosphere

**Time- and spatially-variable aerosols strongly affect the signature of the surface and complicate mineralogic interpretations**

**The surface and atmosphere can be separated by viewing the same surface at different geometries, using "emission phase functions (EPFs)"**

## Emission Phase Functions Provide Valuable Information on Atmospheric Variability

**CRISM will measure emission phase function (EPFs) with each targeted observation**
**Overlapping footprints provide 11 emission angles for central high-res swath**

## Emission Phase Functions Provide Valuable Information on Atmospheric Variability

**Global grids of EPFs will be acquired to measure seasonal variations in aerosols and trace gases**

*** Proof of concept using OMEGA data**

**BD1400H2O: H2O Vapor**

## CRISM Objective 3: Measure sites of interest in unprecedented detail

**CRISM will provide hyperspectral maps at very high spatial / spectral resolution to characterize the geology of key sites **

**Endurance Crater at MER/Opportunity site (squares=CRISM pixels)**

**Spectra of analog materials in CRISM wavelength range**

## Investigation Overview

## CRISM Subsystems and Functions

**Optical Sensor Unit (OSU)**
**Telescope and baffling**
**Dual VNIR and IR spectrometers **
**Actively cooled IR focal plane**
**Passively cooled instrument housing**
**Shutter for interleaved background calibrations**
**Closed-loop, brightness-controlled internal integrating sphere for calibrations**
**Focal plane electronics**
**Gimbaled to ±60°**
**Gimbal Motor Electronics (GME)**
**Controls gimbal motion**

**Data Processing Unit (DPU)**
**Power**
**Control of exposure times, frame rate**
**Data editing, binning, compression **

## Key Aspects of System Performance

## Data Reconstruction (Breccia during ground calibration)

**Data Reconstruction ****(Breccia during ground calibration)**

**Gimbal scan forms a cube of spatial-spectral image frames**

**Cube sliced to produce spatial image**

**Extracted spectrum shows alteration products as sought on Mars**

- Water

- Clay

**1 frame**

## CRISM Data Products / Key Results

***DATA ACQUIRED***
**3000-6000 targeted hyperspectral images at 15-38 m/pixel, 545 wavelengths**
**Global map in ~72 colors, 200 m/pixel**
**3000-10,000 72-channel "windows" at 100 m/pixel**
**Up to 36 global grids of emission phase functions (~5000 observations)**
***ANALYSIS RESULTS***
**Global distribution of major rock types**
**High-resolution mineralogic maps of key sites**
**Seasonal variations in atmosphere**
**Identification / characterization of landing sites for ****Mars Phoenix and MSL**

## CRISM Data Products / Key Results

***DATA ACQUIRED***
**Spectral parameters and mineral indicators (33 surface, 11 atmosphere)****Pelkey et al., 2006 (in prep)**

- Test of parameters with OMEGA data: R: Olivine G: LCP B: HCP

## CRISM Data Products / Key Results

- Test of parameters with OMEGA data: R: Olivine G: LCP B: HCP

***DATA ACQUIRED***
**Spectral parameters and mineral indicators (33 surface, 11 atmosphere)****Pelkey et al., 2006 (in prep)**

## CRISM Data Products / Key Results

- Test of parameters with OMEGA data: R: 1.9 μm G: 2.4 μm B: 2.3 μm

***DATA ACQUIRED***
**Spectral parameters and mineral indicators (33 surface, 11 atmosphere)****Pelkey et al., 2006 (in prep)**

## Basic Data Products: Raw Data

**About 27,000 distinct observations**
**About 320,000 commanded image sequences**
**Each produces a raw data cube like this**
**Every 3 months after 6 months of validation**

## Basic Data Products: Calibrated Targeted Observations

**3000-6000 targeted hyperspectral images + 5000 EPFs **
**Each, once calibrated, yields 11 multi-band images like this**
**Every 3 months after 6 months of validation**

- Standard product

- Special product

## Multispectral Map Tiles

**2500+ multispectral "noodles" mosaicked to create global map**
**72 colors, 200 m/pixel**
**Tiles produced on best-effort basis; every 6 mo. after 6 mo. validation**
**1964 5°x5° tiles**

- Standard product

## Spectral Library to Support Data Analysis

**Searchable database of 1500+ spectra of analog materials**
**CRISM spectral range, measured under Mars-like desiccation**
**Released at Mars orbit insertion**