Sunrise
On Sol 39 there were wispy
blue clouds in the pre-dawn sky of Mars, as seen by the Imager for Mars Pathfinder. The
color image was made by taking blue, green, and red images and then combining them into a
single color image. The clouds appear to have a bluish side and a greenish side because
they moved (in the wind from the northeast) between images. This picture was made an hour
and twenty minutes before sunrise -- the sun is not shining directly on the water ice
clouds, but they are illuminated by the dawn twilight.
These clouds from Sol 15 have
a new look. As water ice clouds cover the sky, the sky takes on a more bluish cast. This
is because small particles (perhaps a tenth the size of the Martian dust, or
one-thousandth the thickness of a human hair) are bright in blue light, but almost
invisible in red light. Thus, scientists expect that the ice particles in the clouds are
very small. The clouds were imaged by the Imager for Mars Pathfinder (IMP).
These are more wispy blue
clouds from Sol 39 as seen by the Imager for Mars Pathfinder. The bright clouds near the
bottom are about 10 degrees above the horizon. The clouds are believed to be at an
altitude of 10 to 15 km, and are thought to be made of small water ice particles. The
picture was taken about 40 minutes before sunrise.
These are more wispy blue
clouds from Sol 39 as seen by the Imager for Mars Pathfinder. The bright clouds near the
bottom are about 30 degrees above the horizon. The clouds are believed to be at an
altitude of 10 to 15 km, and are thought to be made of small water ice particles. The
picture was taken about 35 minutes before sunrise.
On sol 25, as the Hubble Space Telescope was preparing to take images
of mars including the Pathfinder landing site, IMP watched the sunrise. This sequence of
images was taken through the blue filter, and shows the sky just before sunrise continuing
until the Sun rises out of the field of view. These images were taken as part of an
atmospheric imaging project that was coordinated with the Space Telescope observations.
They are also useful for refining our knowledge of the orientation of the landing site --
the position and timing of the sunrise give us a very good direction reference.
Stills of the sunrise with false color.