Mars Spirit Rover
On this day in 2004, the Mars rover Spirit landed on Mars. The rover, and its twin Opportunity, has functioned far longer than its expected lifetime -- it's currently almost 1000 days past its warranty date.
A few facts about the Spirit's software systems:
- The rovers utilize a radiation-hardened PowerPC chip with 128MB of RAM running at approximately 20 MIPS.
- The rovers run a commercial embedded operations system: vxWorks.
- Even NASA has bugs: All storage is in RAM and 256MB of flash. Due to a failure to manually clean up the memory based file system, the Spirit rover ran out of memory early in the mission. The problem was reproduced on earth and corrected.
 Louis Braille
And on this day in 1809, Frenchman Louis Braille, inventor of the Braille alphabet for the blind was born. Braille lost his sight at the age of 3 in an accident. The Braille alphabet he later invented uses a pattern of raised dots that a sight-impaired person can read by touch.
Braille technology has come a long way, though, as there are now Braille printers, copiers, and translation software. Interestingly, although Braille is an "alternate" alphabet, software to do automatic translation can still have difficulties with mathematical symbols, mixed languages, and the special abbreviations that are common in Braille writing.
You can donate help a blind child read Braille.
© 2007, Jorge Monasterio