New Mars Global Surveyor Images Of Cydonia Region

Larry Klaes (
Fri, 23 Jul 1999 18:14:08 -0400

>X-Authentication-Warning: majordom set sender
to owner-astro using -f
>Date: Thu, 8 Jul 1999 19:30:05 GMT
>From: Ron Baalke <>
>Subject: [ASTRO]
New Mars Global Surveyor Images Of Cydonia Region
>Reply-To: Ron Baalke <>
>July 8, 1999
>The following new images taken by the Mars Global Surveyor spacecraft
&gt;are now available:
> o New Cydonia Pictures
>The images reside on the Mars Global Surveyor website:
>The image captions are appended below.
>Mars Global Surveyor was launched in November 1996 and has been
>in Mars orbit since September 1997. It began its primary
>mapping mission on March 8, 1999. Mars Global Surveyor is the
>first mission in a long-term program of Mars exploration known as
>the Mars Surveyor Program that is managed
by JPL for NASA's Office
>of Space Science, Washington, DC. Malin Space Science Systems (MSSS)
>and the California Institute of Technology built the MOC
>using spare hardware from the Mars Observer mission. MSSS operates
>the camera from its facilities in San Diego, CA. The Jet Propulsion
>Laboratory's Mars Surveyor Operations Project operates the Mars Global
>Surveyor spacecraft with its industrial partner, Lockheed Martin
>Astronautics, from facilities in Pasadena, CA and Denver, CO.
>Ron Baalke
> ------------------------------------------------------------------------
> Mars Global Surveyor
> Mars Orbiter Camera
> New Cydonia Picture
> MGS MOC Release No. MOC2-142, 8 July 1999
>The Mars Orbiter Camera (MOC) onboard the Mars Global Surveyor (MGS)
>orbiter, was designed specifically to bridge the gap between what can be
>seen from orbit in typical Mariner 9 and Viking orbiter images, and what can
>be seen from the ground by landers such as Viking 1 and Mars Pathfinder. The
>camera, therefore, takes pictures of extremely high resolution. These images
>are often comparable to aerial photographs used by geologists when they are
>exploring Earth. The highest resolution images that can be obtained are in
>the range of 1.4 to 2.0 meters (4.6 to 6.5 feet) per pixel.
>Last year, several pictures of a portion of the Cydonia region of Mars were
>photographed at lower resolution than is now possible in the Mapping Phase
>of the MGS mission. The Cydonia region is perhaps most "famous" for being
>the location of a feature that--in Viking Orbiter images--seemed to resemble
>a human face. Nearby buttes and hills were considered by some to represent a
>The MGS spacecraft flew over the "famous" Cydonia landforms again--for the
>first time since April 1998--on June 27, 1999, at 10:53 UTC (Greenwich Time
>Zone). The new MOC images shown here provide the highest resolution view yet
>obtained of the "Cydonia city" landforms.
>The picture at the above left (MOC2-142a) shows the regional context.
>Cydonia constitutes a transition zone between the cratered highlands of
>Arabia Terra, and the less-cratered lowlands of Acidalia Planitia. This
>transition zone contains thousands of mesas and buttes--somewhat like the
>Monument Valley region along the Arizona/Utah border in North America. The
>white box shows the location of the new high resolution view of the "city"
>landforms. The image is a red wide angle context frame obtained by MOC at
>the same time that the high resolution view was acquired. The picture is
>illuminated from the lower left, and north is toward the upper right.
>The picture in the center is a processed version of the new MOC narrow angle
>camera image of this portion of Cydonia. You can view either the full-size
>image (MOC2-142b 100% Size) or a half-size image (MOC2-142b 50% size). We
>suggest that you first view the half-size image, because the full image will
>not load on a typical web browser (you will need to "Save this link as..."
>and then view it with your favorite image viewing/processing software).
>Like the context image (above left), the high resolution view (center) is
>illuminated from the lower left. North is toward the upper right. Boulders
>can be seen on some of the hillslopes, and the plains between the hills are
>rough and pitted. To conserve data in order to account for downtrack
>position uncertainties, only 1/2 of the MOC sensor was used to acquire this
>picture (allowing the image to be twice the length): it covers an area that
>is 1.5 km (0.9 mi) wide.
>The picture at the above right is the unprocessed MOC image. This is what
>the processed image (center) looked like before it was rotated 180 (so that
>north is toward the top) and corrected for a 1.5 aspect ratio. The pixel
>size in the unprocessed image is different in the cross-track (left-right)
>and down-track (top-bottom) directions, thus making the craters look
>"squished". The cross-track scale is about 1.5 meters (5 feet) per pixel,
>while the down-track scale is about 2.25 meters (7.4 feet) per pixel. In the
>unprocessed image, the illumination is coming from the upper right. You can
>view this image at full-size (use "Save this link as..." and examine
>MOC2-142c 100% Size) or see it via your web-browser at half-size (MOC2-142c
>50% Size).