About 12 metres (39 ft) from the landing site, Sleepy Hollow measures about 9 metres (30 ft) across.
The name is an allusion to the locale mentioned in Washington Irving's 1819 story "The Legend of Sleepy Hollow". According to a press conference, it was the hollow where Spirit slept as it was checked before beginning to rove Mars.
This image shows the Martian terrain through the eyes of the Mars Exploration Rover Spirit's mini-thermal emission spectrometer, an instrument that detects the infrared light, or heat, emitted by objects. The different colored circles show a spectrum of soil and rock temperatures, with red representing warmer regions and blue, cooler. A warm and dusty depression similar to the one dubbed Sleepy Hollow stands out to the upper right. Scientists and engineers used this data to pinpoint features of interest, and to plot a safe course for the rover free of loose dust. The mini-thermal emission spectrometer data are superimposed on an image taken by the rover's panoramic camera.