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1993-04-21
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OFFICE OF PUBLIC EDUCATION AND INFORMATION
JET PROPULSION LABORATORY, CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIFORNIA. TELEPHONE 354-5011
The following statement was released 3:00 PM EST, November 18,
1964, by NASA Headquarters, Washington, D.C.
NASA SCHEDULES MARINER D LAUNCH NO EARLIER THAN NOVEMBER 27
National Aeronautics and Space administration officials
are preparing the Mariner D spacecraft for launch on a Mars
trajectory within the current launch opportunity. The launch of
Mariner D, now undergoing final checkout at Cape Kennedy, has
awaited analysis of the failure of the Mariner 3 mission launched
November 5.
If current tests of Mariner, its Atlas/Agena launch
vehicle, and the aerodynamic fairing protecting the spacecraft
during powered flight goes well, Mariner D will be launched no
earlier than November 27.
After a detailed analysis of the Mariner 3 launch
project officials concluded that the fairing did not completely
jettison as scheduled some 5 1/2 minutes after launch. The space-
craft could not deploy its solar panels and its battery was
drained about 9 hours after launch.
Investigation indicated that the fairing, made of a
light weight fiberglass, laminated, honeycombed structure,
probably had a structural failure when exposed to the flight
environment. This prevented shroud separation from the space-
craft.
As a result, a decision was made to design and fabricate
a metal shroud section to replace the fiberglass section. This
work is being done under direction of NASA's Lewis Research
-2-
Center, Cleveland, at Lockheed Missile and Space Company,
Sunnyvale, California, on a 24-hour-day, 7-day-week schedule.
One metal shroud, made of a light weight magnesium alloy, has
been completed and is now being tested by Lockheed. A second
metal shroud is currently being fabricated.
If the testing goes well, it is planned that the first
of the metal shrouds will be shipped to Cape Kennedy this weekend
so that all system checks can be conducted on the spacecraft/
launch vehicle combination at Complex 12 next week.
The Lewis Center also has ordered removal of the command
destruct system from the Agena second stage of the launch vehicle.
The command system is being replaced by a self destruct system.
This is similar to the Atlas/Agena configuration which launched
the first six Rangers and the first two Mariners. This modifica-
tion, which reduces the weight of the Agena by about 30 lbs.,
could gain a few days in the current Mars launch opportunity. It
could also off-set the slightly increased weight -- about 50 lb.
-- resulting from the proposed switch to a metal fairing.
Current launch opportunity for Mars opens November 4
for about a one month period. The rapid failure analysis and
resulting modifications were necessary because a Mars launch
opportunity occurs only once every 25 months. Failure to launch
in 1964 would mean either cancellation of the Mariner D or a two
year storage period with a launch attempt in 1966.
OFFICE OF PUBLIC EDUCATION AND INFORMATION
CALIFORNIA INSTITUTE OF TECHNOLOGY JET PROPULSION LABORATORY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIFORNIA. TELEPHONE 354-5011
FOR RELEASE: A.M.'s of Friday, August 21, 1964
__________________________
The National Aeronautics and Space Administration will
launch two Mariner space vehicles in the fourth quarter of this
year to begin the first step by the United States in the explora-
tion of Mars with unmanned spacecraft.
This is the most complex mission to be attempted to
date in the U.S. unmanned space program.
Objectives for these first Mariners will be to explore
interplanetary space between Earth and Mars and to validate new
engineering techniques that will be used for the first time in
this mission.
The decision to launch two spacecraft on the same
mission was dictated by the difficult engineering task that the
Mars mission represents and by the necessity of utilizing untried
engineering advancements to achieve any probability of success.
The two Mariners will be prepared simultaneously on
separate launch pads because of the relatively short opportunity
for a Mars launch. The second spacecraft will be launched as
soon as practical after the first. The period in which a space-
craft can be launched to Mars lasts only a few weeks and occurs
only once every 25 months.
An Atlas-D/Agena-D combination will be used to launch
the Mariners. Maximum performance demands have been placed on
these vehicles for this mission.
-2-
Management and technical direction for the Mariner Pro-
ject is assigned by NASA's Office of Space Science and Applica-
tions to the California Institute of Technology Jet Propulsion
Laboratory. This includes responsibility for the spacecraft,
space flight operations, and deep space tracking and communica-
tions. The Atlas/Agena launch vehicles are under direction of
NASA's Lewis Research Center, Cleveland, and will be launched by
Goddard Space Flight Center's Launch Operations from Cape Kennedy,
Florida.
Interplanetary scientific equipment on the Mariners will
report on radiation, magnetic fields, and micrometeorites.
If either Mariner is functioning at planet encounter,
planetary experiments will return television pictures and other
measurements of the planet.
Future exploration of Mars will require landing an
instrumented capsule on the surface to perform biological
experiments. Designing a capsule, however, requires accurate
information on the density of the Martian atmosphere. Current
scientific estimates vary over a wide range.
Therefore, an attempt will be made to make a measurement
of the Martian atmosphere in the Mariner-Mars 64 mission.
This will be accomplished by selecting a spacecraft
trajectory that will cause the spacecraft to pass behind Mars and
to be occulted from Earth. Prior to occultation the tracking
signal transmitted from the spacecraft will pass through the
Martian atmosphere. The effects of the atmosphere on this radio
-3-
signal will yield information on the varying density of the
Martian atmosphere. One or both of the Mariners may perform this
experiment.
It is expected that the proximity of Mars to the
asteroid belt may produce a higher incidence of micrometeorites
than was the case in the flight of Mariner II from Earth to Venus
in 1962. Part of the exploratory nature of the first Mars mission
will be to determine if micrometeorites constitute a serious
hazard in flights to Mars.
The first Mars mission will also yield important data on
space navigation over tremendous distances and on the capability
of powering a spacecraft by converting sunlight to electricity
during a mission in which the Sun-spacecraft distance is steadily
increasing. The Mars Mariners will be equipped with four solar
panels as compared with two for Mariner II and the Ranger lunar
impact spacecraft.
Unprecedented distances in space are involved in this
mission. At launch, the Mariners will be aimed along a
trajectory between the orbits of Earth and Mars, which will be
some 350 million miles long. At time of encounter, Mars and
Earth will be about 150 million miles apart.
The Mariner Mars spacecraft will weigh approximately
570 pounds with a span of 22 feet, panel extended, and a height
of 9-1/2 feet. Flight times vary, relative to day of launch,
from 7-1/2 months to 8-1/2 months with an additional three weeks
of flight beyond the planet needed to return data.
-4-
This mission will utilize the following technical
advancements for the first time:
1. High frequency radio communication. The communica-
tion distance of more than 150 million miles. This compares with
53.9 million miles achieved for the 1962 Mariner II Venus mission.
2. A midcourse guidance rocket engine that can be fired
twice. Earlier spacecraft have not had a re-start cpaability.
3. First use of the Agena-D second stage and first use
of the Atlas-D with many improvements.
4. First use of the star Canopus for spacecraft
attitude reference.
The long duration of the mission requires that the
Mariners survive in space for a minimum of nine months. The
longest previous life-time requirement for a U.S. deep space probe
was 3-1/2 months for the Mariner II Venus mission.
The nine-month flight requirement is applied to some
138,000 component parts for the Mariner Mars spacecraft compared
with 54,000 component parts for the Mariner II.
###
298 - 8/19/64