Pre-Planning the Last Chance

This graphic is a computer-generated visualization tool used by Opportunity scientists to find the roverÕs best position for 
observing a future target of interest dubbed "Last Chance."  Team members are planning how to photograph the optimal 
angle of this layered rock on the far-east end of the outcrop. The rockÕs location will force the rover drivers to solve very 
complex geometry calculations in order to get the cameras at just the right distance from the rock with exactly the right 
illumination by the sun. If the rover is parked to the west of the target and the sun is setting in the west when the rover is 
commanded to take the picture, the rover will cast a shadow on the prime location and important features in the image will 
be lost in the dark.  

The planning of this particular photo of Last Chance is particularly complex because the uneven terrain underneath the 
rover will also cause the camera angle to tilt.  All six of the rover wheels will be sitting on varied levels of rock and soil, 
creating a more difficult camera aiming challenge.  The rock area itself is at a right angle, which further complicates things 
because the science team wants to take pictures from two sides of the rock to get the whole story of how this rock formed.

The number of pictures the science team wants to take of this site adds yet another layer of necessary forethought in that 
the flash memory must be empty enough to record the large images and store them before transmitting the data back to 
Earth.  Three sols in advance of taking the pictures, the Long Term Planning team is asking the science team to conserve 
data volume to allow the onslaught of new panoramic camera images around sol 36. 

The rover visualization team from NASA Ames Research Center, Moffett Field, Calif., created the visualization software 
from terrain models built with data collected via the panoramic camera images sent from the surface of Mars.  The 
computer model of the rover is very detailed, containing precise dimensions of the roverÕs mast and camera locations in 
relation to the entire body and wheels of the rover to an accuracy of centimeters.  The rover model was based on 
animations and drawings designed by Dan Maas at Maas Digital LLC. 

Image Credit:  NASA/JPL

APPROVED BY:  Larry Soderblom, SOWG chair, and John Grotzinger Š grotz@mit.edu

CAPTION WRITER:  Christine Johnson 818/667-7853 cell

RELEASE DATE:  February 27, 2004

IMAGE FILE NAME: xpe_last_chance_viz.jpg

SOURCE FILE NAME(S): Larry Edwards Viz Image in MERSCI/OSS/Pan/Viz/Screenshots/big_bend

SUMMARY INFORMATION:  Viz image of Opportunity area

NAME OF SUBMITTER:  John Grotzinger

INSTITUTION:  MIT

THEME/TEAM/GROUP:  Long Term Planning

SOL OF OBSERVATION:  33

EARTH DATE OF OBSERVATION:  February 26, 2004

TITLE OF IMAGE: Pre-Planning the Last Chance

CAPTION:  Above



<br> USERNAME: cjohns