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1993-04-21
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OFFICE OF PUBLIC INFORMATION
JET PROPULSION LABORATORY, CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIFORNIA. TELEPHONE 354-5011
MARINER '69 FACT SHEET
The National Aeronautics and Space Administration will
launch two Mariner spacecraft, F & G, on fly-by missions to Mars
in 1969. Project responsibility is assigned to the Jet
Propulsion Laboratory of the California Institute of Technology.
NASA's Lewis Research Center, Cleveland, is responsible for the
launch vehicle. Tracking and communication will be provided by
the Deep Space Net stations operated by JPL for NASA.
The Mariner Mars '69 launch period falls between mid-
February and mid-April. The spacecraft will arrive at Mars
between the end of July and mid-August.
The first spacecraft will be launched as early in the
period as possible the second as late as possible. The arrival
dates will not be less than five days apart.
The launch vehicle for this mission is the Atlas/Centaur
combination; the first time this combination has been used for
planetary exploration. The spacecraft will weigh approximately
900 pounds compared with 575 pounds for the Mariner Mars '64
mission.
All scientific experiments aboard the Mariner '69 are
planet-oriented with particular emphasis on providing data on the
atmosphere and surface of Mars. The experiments aboard Mariner
'69 are as follows:
-2-
__________ _______ ______________________
Infrared Measure the infrared Dr. G. C. Pimentel
Spectrometer spectral energy from the University of California
lower atmosphere and Berkeley
surface at 1.9 to 14.7
microns.
Infrared Measure thermally emitted Dr. G. Neugebauer
Radiometer energy from the surface California Institute of
in the regions of 8.0 to Technology
12.0 and 18.0 to 25.0
microns.
Ultraviolet Detect the presence and Dr. C. A. Barth
Spectrometer scale height of atmos- University of Colorado
phere constituents by Boulder, Colorado
measurements in the 1100
to 4500 Angstrom region.
Television Photograph planetary disc Dr. R. B. Leighton
and surface California Institute of
Technology
S-Band Determined atmospheric Dr. A. J. Kliore
Occultation surface pressure and den- Jet Propulsion Laboratory
sity and variations with
height and latitude.
Celestial Refine accuracy of the Dr. J. D. Anderson
Mechanics Earth and Mars orbits, Jet propulsion Laboratory
Mars Mass, Earth-Moon
mass ratio and the
astronomical unit.
On currently designed trajectories the two spacecraft
will fly-by Mars at a closest approach distance of approximately
2000 miles. In the 1964 mission the closest distance was 6000
miles. The extremely close approach, which will occur when Mars
is about 62 million miles from Earth, includes a 30,000 to 1
probability that the spacecraft will not impact and contaminate
the planet Mars.
-3-
The two camera systems, wide-angle and narrow angle
aboard each spacecraft will provide narrow angle photographs of
the disc of Mars as it revolves in front of the approaching
spacecraft during far-encounter, and both wide-and narrow-angle
pictures of the planet's surface during the near-encounter fly-by.
The best resolution of the full disc pictures will be
about 1 1/2 miles; the resolution of the near-encounter pictures
about 3000 yards for the wide angle camera and 300 yards for the
narrow angle camera. The Martian moon Phobos may be visible in
some of the approach pictures.
A minimum of thirty-three TV pictures will be obtained
by each spacecraft. At least eight of the pictures will be at a
range which will show the entire disc of the planet (far-encoun-
ter). (Optional sequences under consideration can provide
additional far-encounter pictures).
The remaining twenty-five pictures will be taken as the
spacecraft fly past the planet, (near-encounter).
The Infrared Radiometer (IRR), Infrared Spectrometer
(IRS) and Ultraviolet Spectrometer (UVS) will scan the same areas
photographed by the two cameras to allow correlation of data.
They will also scan the planet's dark side. Data from the IRR,
IRS and the UVS will yield information on temperatures in the
atmosphere and at the surface and the composition of the upper
and lower atmosphere.
Mariner '69 design is based upon the successful Mariner
missions to Venus 1962, Mars 1964, and Venus 1967. Comparison
-4-
between 1964, and Venus 1967. Comparison between 1964 and 1969
reflect the growth and improvements in the Mariner class
spacecraft.
____________ ____________
Weight 575 lbs. 900 lbs.
Transmitter 10 watts 20 watts
Bits per second 8 1/3 270 and 16,200
Bits per picture 240,000 3,991,680
Record time per picture 24 sec. 42.24 sec.
Weight of Science Instruments 60 lbs. 141.18 lbs.
Closest approach 6118 miles 2000 miles
Mariner 1969 has been designed to provide a number of
options in the operation of the two spacecraft after launch if
in-flight performance and the availability of ground tracking
facilities permit. The options will allow enhancement of mission
results.
Encounter of the two spacecraft with Mars will be
designed to allow one spacecraft to fly-by the Southern polar cap
and the other near the Equator. The point of closest approach
will occur over the tracking and communication station of the
Deep Space Net Station at Goldstone, California.
Program Manager for Mariner Mars '69 is N. W.
Cunningham, of the Office of Space Science and Application, NASA,
Washington.
Harris M. Schurmeier, is Project Manager for the Mars
mission for the Jet Propulsion Laboratory.
###
472/5/15/68