Two Worlds, One Sun
Explanation:
Two Worlds, One Sun,
is the legend emblazoned on the Spirit
rover's camera calibration target.
Resting on the rover's
rear deck,
it also
doubles
as a sundial, allowing
students
to determine the solar time at Spirit's landing
site on Mars.
Examples of the
sundial
or Marsdial
are shown above where
the left image, captured near local noon, shows the effect of
the Sun high in the martian sky.
The right image from the later in the afternoon with the
Sun lower in the sky, shows a long shadow cast by the Marsdial's
central post.
Based on the computer generated grid overlay, students
determined the local time in the
central inset image to be
about 12:17 pm local solar time.
Did you know,
the Marsdial idea was a brainchild of
Bill
Nye, the Science Guy?
(
Now
you know ...)
Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell
(USRA)
NASA Web Site Statements, Warnings,
and Disclaimers
NASA Official: Jay Norris.
Specific
rights apply.
A service of:
LHEA at
NASA /
GSFC
& Michigan Tech. U.
