[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Mars Global Surveyor Update - October 3, 1997

Mars Global Surveyor
Flight Status Report 
Friday, 3 October 1997

     Earlier this week, excited investigators representing several of 
Surveyor's science teams held a press conference at the Jet Propulsion 
Laboratory to announce initial findings from the first half-month of data 
collection. Although full-scale investigations will not begin until 
aerobraking is completed early next year, the science teams have already 
obtained several close-up images of the Martian surface, discovered 
sources of magnetic anomalies buried in the planet's crust, measured 
surface and atmosphere temperatures, and obtained topographical data 
about rifts much deeper than the Grand Canyon. 

     For more information about these initial findings, please visit the 
following page on the Surveyor web site:

http://mars.jpl.nasa.gov/mgs/sci/sci.html

     This page contains links to explanations about the initial science 
results, graphical illustrations used by the scientists at the press 
conference, and a download archive of images taken by the camera since 
orbit insertion.

     Meanwhile, aerobraking continues to proceed smoothly after 13 
revolutions around the red planet. At the start of aerobraking operations 
two weeks ago, the altitude of the orbit's high point was 33,570 miles 
(54,025 km). As of today, that height has dropped down to 30,304 miles 
(48,770 km). Over the next four months, the high-point altitude will 
shrink all the way down to 280 miles (450 km).

     Passes through the atmosphere now occur once every 39 hours as the 
spacecraft skims through the low point of its orbit 68.4 miles (110 km) 
above the Martian surface. At this altitude, air resistance slows 
Surveyor by about 6.7 m.p.h. (3 meters per second) on each orbit. 
Although aerobraking deeper in the atmosphere will accelerate the process 
of shrinking the orbit, spacecraft safety constraints prohibit passes at 
altitudes significantly lower than the current value.

     In addition to shrinking the size of Surveyor's orbit, aerobraking 
has also had a positive effect on the solar panel that deployed about 20 
degrees short of its final position just after launch. This position 
discrepancy resulted when part of the panel's deployment mechanism broke 
and wedged into the hinge connecting the panel to the spacecraft. During 
the most recent atmospheric passes, the force of the oncoming air flow 
has been strong enough to force the panel back into position despite the 
presence of debris in the hinge. The panel is now less than one degree 
from its proper position.

     After a mission elapsed time of 330 days from launch, Surveyor is 
167.81 million miles (270.07 million kilometers) from the Earth and in an 
orbit around Mars with a period of 39.25 hours. The spacecraft is 
currently executing the P14 command sequence, and all systems continue to 
be in excellent condition.

---------------------------------------
Status report prepared by:
 
Office of the Flight Operations Manager
Mars Surveyor Operations Project
NASA Jet Propulsion Laboratory
California Institute of Technology
Pasadena, CA 91109
---------------------------------------