PIA03612: Spirit View of Phobos Eclipse, Sol 675

Spirit View of Phobos Eclipse, Sol 675


Click here for PIA03612 Spirit View of Phobos Eclipse, Sol 675
Annotated Spirit View of Phobos Eclipse, Sol 675

NASA's Mars Exploration Rover Spirit observed the Martian moon Phobos entering the shadow of Mars during the night of the rover's 675th sol (Nov. 27, 2005). The panoramic camera captured 16 images, spaced 10 seconds apart, covering the period from when Phobos was in full sunlight to when it was entirely in shadow. As with our own Moon during lunar eclipses on Earth, even when in the planet's shadow, Phobos was not entirely dark. The small amount of light still visible from Phobos is a kind of "Mars-shine" -- sunlight reflected through Mars' atmosphere and into the shadowed region.

This view is a time-lapse composite of images taken 20 seconds apart, showing the movement of Phobos from left to right. (At 10 seconds apart, the images of the moon overlap each other.) Scientists are using information about the precise timing of Martian moon eclipses gained from observations such as these to refine calculations about the orbital path of Phobos. The precise position of Phobos will be important to any future spacecraft taking detailed pictures of the moon or landing on its surface.

Cataloging Keywords:

Name Value Additional Values
Target Phobos Earth, Mars, Moon, Sun
System Mars Earth
Target Type Satellite Earth, Planet, Sun
Mission Mars Exploration Rover (MER)
Instrument Host Spirit (MER-A)
Host Type Rover
Instrument Panoramic Camera (Pancam)
Extra Keywords Atmosphere, Eclipse, Grayscale, Shadow
Acquisition Date
Release Date 2005-12-05
Date in Caption 2005-11-27
Image Credit NASA/JPL-Caltech/Cornell/Texas A&M/SSI
Source photojournal.jpl.nasa.gov/catalog/PIA03612
Identifier PIA03612