IDL and ENVI Aid in Martian Discoveries
Anonym
Customer Challenge
Mars Rover image analysts needed an easily customized solution to visualizing and analyzing data from imaging instruments deployed on Mars.
Solution Achieved
The goal of the Mars exploration mission was to answer questions posed for generations: what is the history of water on Mars, and what is the potential that life could, or ever did, exist on the planet?
The mission produced enormous amounts of data. To gather data for eventual analysis with ENVI® and IDL®, Farrand and other researchers on the team plot the rovers’ daily activities by identifying areas of interest on the Martian landscape and directing them to those regions. Spectacular high resolution imaging is achieved using a pair of Panoramic Cameras, or Pancams, one mounted on each rover, which provide stereo imagery, as well as a full panoramic, three-dimensional view of the surface around each rover. Each piece of data will eventually require visualization and analysis.
A set of IDL routines, developed by scientists and engineers at Cornell University, helps analysts and scientists work with the specific types of imagery returned by the rovers. The set of programs called “Mertools” by the team, is used for monitoring camera health, data tracking, and some data analysis functions. The data are gathered each Martian day, compressed on-board and sent to Earth in both direct-to-Earth transmissions and transmissions relayed by the orbiting Mars Odyssey spacecraft.
IDL’s role in the mission doesn’t end with managing the cameras and their data. Understanding the enormous amount of data sent from Spirit and Opportunity each day is a complex task. Farrand, who works extensively with the downloads of Pancam data, uses ENVI and IDL to sort, manage, examine and create files from each data product. Analyzing extraordinary amounts of data each day can be tedious, but Farrand says that the ease and convenience of the IDL environment saves him time. “I don’t think there is another processing package that has the breadth and depth of spectral tools. ENVI and IDL allow you to plug in additional capabilities to customize your data analysis.”
Once Farrand has verified the data with IDL, he uses ENVI and IDL routines he developed to get an idea of what kinds of spectrally distinct rocks and soils exist on the red planet. IDL’s functionality provides him with a set of powerful image processing tools from which to build a customized version of the linear spectral mixture analysis and matched filter routines. Using ENVI’s suite of spectral tools, he also performs classifications of, and information extraction from the multispectral Pancam images.
Farrand also uses ENVI’s integral spectral library to relate the broadband spectra of materials on the surface of Mars to those of laboratory-measured minerals on Earth. One ENVI routine which Farrand uses repeatedly in his research is the decorrelation stretch tool which enhances subtle color difference in Martian rocks and soils.
Key Benefits
- Using the ENVI and IDL solution, scientists and researchers have a host of built-in, powerful routines to manage, analyze and visualize huge datasets. In addition, they can extend IDL to create their own, custom routines.
- Built-in routines save time, money and effort on the part of the scientists.
- There is not another tool that has the breadth and depth of spectral tools. ENVI and IDL allow you to plug in additional capabilities to customize your data analysis.