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1989-08-10
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W E L C O M E
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NASA SPACELINK
A Space-Related Informational Database
Provided by the NASA Educational Affairs Division
Operated by the Marshall Space Flight Center
On a Data General ECLIPSE MV7800 Minicomputer
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AOS/VS 7.60.00.00 / EXEC-32 7.60.00.00 10-Aug-89 20:01:19 @CON4
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MESSAGE
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automatically deleted from the system.
Check main menu option 3, subs 10, 11 & 12 for the latest Magellan/Venus
and Voyager/Neptune status reports.
The Shuttle and Mixed-Fleet Manifests (schedules of launches) are posted
under main menu option 3.
For info on future plans, check main menu option 6, submenu 11--NASA's
1989 Long Range Program Plan.
--------
Last previous logon 7-Aug-89 20:54:54
NASA/SPACELINK MENU SYSTEM Revision:1.32.00.00
NASA Spacelink Main Menu
1. Log Off NASA Spacelink
2. NASA Spacelink Overview
3. Current NASA News
4. Aeronautics
5. Space Exploration: Before the Shuttle
6. Space Exploration: The Shuttle and Beyond
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10. Space Program Spinoffs
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Current NASA News
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3..NASA News Releases
4..Shuttle Status Reports
5..Recent NASA Speeches
6..Shuttle and Other Manifests (Launch Dates)
7..1988 In Review
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10.Magellan Status Reports
11.Voyager Status Reports
12.Voyager Neptune Encounter Info
13.STS-28 (Current Shuttle Mission)
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Kennedy Space Center Shuttle Processing Reports
0..Return to Previous Menu 1..Return to Spacelink Main Menu
2..THURSDAY AUG. 10 1989
3..WEDNESDAY AUG. 9 1989
4..STS-28 Solid Rocket Booster Recovery Status
5..MONDAY AUG. 7 1989
6..SUNDAY AUG. 6 1989
7..SATURDAY AUG. 5 1989
8..FRIDAY AUG. 4 1989
9..WEDNESDAY AUG. 2 1989
10..MONDAY JULY 31 1989
11..FRIDAY JULY 28 1989
12..THURSDAY JULY 27 1989
13..SHUTTLE STATUS 7-25-89
14..MONDAY JULY 24 1989
15..FRIDAY JULY 21 1989
16..THURSDAY JULY 20 1989
17..WEDNESDAY JULY 19 1989
18..TUESDAY JULY 18 1989
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THURSDAY, AUG. 10, 1989
STS-28 - COLUMBIA (OV 102) - LAUNCH PAD 39-B
Landing is scheduled on Sunday, Aug. 13 at Edwards Air Force
Base, Calif. during a period from 9 a.m. to 12 noon EDT.
Mobile Launcher Platform 2 is being transferred from Pad B
to the VAB today.
Both solid rocket boosters are at Hangar AF where detailed
post-launch inspections, hydrolasing activities and disassembly
are scheduled over the next two weeks. The segments will be
shipped back to Morton Thiokol in Utah for refurbishment.
STS-34 - ATLANTIS (OV 104) - OPF BAY 2
Closeouts of the payload bay are underway in preparation for
door closure scheduled for Sunday. The Ku-band antenna has been
stowed for flight. Tonight several check valves in the main
propulsion system are scheduled to be replaced. This morning, 29
tile cavities were reported. A functional test of the landing
gear is planned for Sunday. Schedulers are targeting to move
Atlantis to the Vehicle Assembly Building at midnight on August
18.
STS-33 - DISCOVERY (OV 103) - OPF BAY 1
Power up operations and systems testing are planned today.
Modifications and tile work are underway. Operations scheduled
today include, testing of the waste containment system,
inspections of thermal blankets and leak checks of the helium
system. Installation of the main landing gear brakes is
scheduled today.
STS-34 SOLID ROCKET BOOSTERS/EXTERNAL TANK - VAB
Closeouts of the STS-34 external tank and solid rocket
boosters are underway this week.
STS-33 SOLID ROCKET BOOSTERS - RPSF
Buildup of the left and right aft boosters for the STS-33
mission is continuing at the Rotation Processing and Surge
Facility. Stacking is scheduled to begin later this month.
MOBILE LAUNCHER PLATFORM 3 - VAB
Mobile Launcher Platform 3 has been undergoing modifications
in the VAB to bring it "on-line" to support Space Shuttle
launches. It was transferred to Pad A yesterday for several weeks
of interface verification testing before going back to the VAB.
(Yesterday's status report incorrectly stated transfer to the Pad
would occur today.) MLP 3 is currently scheduled to support the
STS-32 launch of Columbia in December.
# # # # #
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STS-28 Solid Rocket Booster Recovery Status
Aug. 9, 1989, 10:30 a.m.
Both boosters from the STS-28 launch of Columbia were success-
fully taken under tow Tuesday by crews of the two recovery ships.
Initial observation of the boosters by retrieval team members has
revealed no discrepancies other than one missing booster separa-
tion motor cover from the frustum (nose cone) of the lefthand
booster. The cover is a hinged metal door which springs open
during separation motor firing and serves as a protective cover
for the separation motor. There have been occasional instances
in the past of the covers, which are approximately eight inches
in diameter, detaching from their hinges.
The recovery ship Freedom, towing the lefthand booster, is ex-
pected to arrive at Port Canaveral between 1 and 1:30 p.m. EDT
today. The Liberty, towing the righthand booster, is experienc-
ing difficulties with the clutch of one engine and is expected
about 9 p.m.
The solid rocket booster disassembly and evaluation team is in
place at Canaveral Air Force Station and will begin their assess-
ment upon arrival of the boosters at Hangar "AF." Actual disas-
sembly of the hardware will begin next week.
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Kennedy Space Center Shuttle Processing Reports
0..Return to Previous Menu 1..Return to Spacelink Main Menu
2..THURSDAY AUG. 10 1989
3..WEDNESDAY AUG. 9 1989
4..STS-28 Solid Rocket Booster Recovery Status
5..MONDAY AUG. 7 1989
6..SUNDAY AUG. 6 1989
7..SATURDAY AUG. 5 1989
8..FRIDAY AUG. 4 1989
9..WEDNESDAY AUG. 2 1989
10..MONDAY JULY 31 1989
11..FRIDAY JULY 28 1989
12..THURSDAY JULY 27 1989
13..SHUTTLE STATUS 7-25-89
14..MONDAY JULY 24 1989
15..FRIDAY JULY 21 1989
16..THURSDAY JULY 20 1989
17..WEDNESDAY JULY 19 1989
18..TUESDAY JULY 18 1989
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Current NASA News
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10.Magellan Status Reports
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12.Voyager Neptune Encounter Info
13.STS-28 (Current Shuttle Mission)
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STS-28
Note: This is a classified Department of Defense mission. Very little
information on the flight will be available.
0..Previous Menu
1..Main Menu
2..Launch Advisory
3..Orbiter Modifications
4..Mission Control Statement
5..Mission Control 24 Hours Statement
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STS-28 Statement
8 August 1989
This is Mission Control, Houston at 2 hours 12 minutes into the
flight of Columbia.
The crew of Columbia has been given a go for orbit operations.
The ship is performing well. There are no systems problems to
report aboard Columbia. The crew is doing well and again they
have been given the go for orbit operations.
This concludes our commentary for today on the flight of
Columbia, STS-28 at mission elapsed time of 2 hours 13 minutes.
This is Mission Control, Houston.
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LAUNCH + 24 HOUR ANNOUNCEMENT
"This is Mission Control, Houston, with an advisory on the flight
of Columbia. The advisory follows in 30 seconds:
The landing period for Shuttle mission STS-28 is a three-hour
window between the hours of 8 a.m. and 11 a.m. CDT, on August
13th. Landing is scheduled for Edwards AFB, California.
Meanwhile, the STS-28 crew is doing well and the Columbia
continues to perform satisfactorily."
====PRESS RETURN TO CONTINUE====
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STS-28
Note: This is a classified Department of Defense mission. Very little
information on the flight will be available.
0..Previous Menu
1..Main Menu
2..Launch Advisory
3..Orbiter Modifications
4..Mission Control Statement
5..Mission Control 24 Hours Statement
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10.Magellan Status Reports
11.Voyager Status Reports
12.Voyager Neptune Encounter Info
13.STS-28 (Current Shuttle Mission)
Enter a number or press RETURN to redisplay menu...10
Magellan Status Reports
0..Return to Previous Menu 1..Return to Spacelink Main Menu
2..MAGELLAN WEEKLY STATUS August 7 1989
3..MAGELLAN WEEKLY STATUS July 25 1989
4..MAGELLAN WEEKLY STATUS July 17 1989
5..MAGELLAN WEEKLY STATUS July 11 1989
6..MAGELLAN WEEKLY STATUS June 26 1989
7..MAGELLAN WEEKLY STATUS June 20 1989
8..MAGELLAN WEEKLY STATUS June 13
9..MAGELLAN WEEKLY STATUS June 6
10..MAGELLAN WEEKLY STATUS May 30-June 3 1989
11..MAGELLAN STATUS May 26 1989
12..MAGELLAN STATUS May 25 1989
13..MAGELLAN STATUS May 24 1989
14..MAGELLAN STATUS May 23 1989
15..MAGELLAN STATUS May 22 1989
16..MAGELLAN STATUS May 19 1989
17..MAGELLAN STATUS May 18 1989
18..MAGELLAN STATUS May 17 1989
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The following document was updated on 08-09-89 and contains 1931 characters.
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MAGELLAN WEEKLY STATUS August 7, 1989
This is a weekly status report. The Magellan spacecraft
continues to perform twice daily momentum wheel desaturations and
once daily star calibrations for attitude update. Numerous
additional Starcals were performed to calibrate the star scanner
to future guide stars and safing stars.
Continuing solar activity during the past week has resulted
in spurious interrupts in the star tracker for four of the daily
attitude update Starcals and two of the star scanner
calibrations. Seven Starcals were fully successful.
On August 1, the operations team performed the first
calibration of the High-Gain Antenna (HGA), involving a series
of spacecraft maneuvers to sweep two axes of the HGA across the
Deep Space Network (DSN) station. The HGA maneuver went well with
solid signals throughout the sweep, but the Starcal performed
before the HGA calibration had a spurious interrupt and
contaminated the initial attitude accuracy. The data is being
corrected to allow a computation of HGA misalignment.
Results of testing at Rocket Research show no performance
loss for the half-pound thruster or the five-pound thruster at
110 degrees C (230 F). The 100-pound engine did produce lower
impulse-bits during tests at 120 C (248 F) and 90 C (194 F), but
it is unclear if this is temporary or permanent. The answer will
remain unresolved until the final tests.
Computer sequence C-8 was uploaded August 4 and execution
began on August 7. Final sequence development for C-9 will
commence following approval of final sequence planning and
preliminary sequence development for C-10 has begun.
SPACECRAFT
Distance From Earth (mi) 16,173,246
Velocity Geocentric 16,458 mph
Heliocentric 72,992 mph
One Way Light Time 86.8 seconds
====PRESS RETURN TO CONTINUE====
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Magellan Status Reports
0..Return to Previous Menu 1..Return to Spacelink Main Menu
2..MAGELLAN WEEKLY STATUS August 7 1989
3..MAGELLAN WEEKLY STATUS July 25 1989
4..MAGELLAN WEEKLY STATUS July 17 1989
5..MAGELLAN WEEKLY STATUS July 11 1989
6..MAGELLAN WEEKLY STATUS June 26 1989
7..MAGELLAN WEEKLY STATUS June 20 1989
8..MAGELLAN WEEKLY STATUS June 13
9..MAGELLAN WEEKLY STATUS June 6
10..MAGELLAN WEEKLY STATUS May 30-June 3 1989
11..MAGELLAN STATUS May 26 1989
12..MAGELLAN STATUS May 25 1989
13..MAGELLAN STATUS May 24 1989
14..MAGELLAN STATUS May 23 1989
15..MAGELLAN STATUS May 22 1989
16..MAGELLAN STATUS May 19 1989
17..MAGELLAN STATUS May 18 1989
18..MAGELLAN STATUS May 17 1989
Enter a number or press RETURN to redisplay menu...0
Current NASA News
0..Previous Menu
1..Main Menu
2..NASA Educational Programs
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5..Recent NASA Speeches
6..Shuttle and Other Manifests (Launch Dates)
7..1988 In Review
8..NASA/Lewis Satellite TV Schedule
9..NASA in the News/NASA Select TV Schedule (Public Affairs Programs)
10.Magellan Status Reports
11.Voyager Status Reports
12.Voyager Neptune Encounter Info
13.STS-28 (Current Shuttle Mission)
Enter a number or press RETURN to redisplay menu...11
Voyager Status Reports
0..Return to Previous Menu 1..Return to Spacelink Main Menu
2..Voyager Status Report August 8 1989
3..Voyager Status Report August 2 1989
4..Voyager Status Report August 1 1989
5..Voyager Status Report July 25 1989
6..Voyager Status 7/18
7..Voyager Status Report July 11 1989
8..Voyager Status Report July 7 1989
9..Voyager Status Report July 5 1989
10..Voyager Status Report 6/27
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The following document was updated on 08-08-89 and contains 1711 characters.
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Voyager Status Report August 8, 1989
Voyager 2 moved into its "far encounter" phase Sunday,
stepping up its studies of the planet's atmospheric features
and continuing searches for new moons and possible ring arcs.
More than two dozen previously planned photographs of
the Neptune system have been repointed toward interesting
atmospheric features such as the large dark spot and the
bright, fast-moving clouds (dubbed "scooters" by the science
team) that move along the top edge of the dark southern
latitudinal band.
Studies of features in the atmosphere are yielding
preliminary calculations of Neptune's wind speeds. Winds on
Neptune at 55 degrees south latitude seem to blow at a
roaring 400 miles per hour -- similar to the wind speed in
the same region on Uranus.
Mission controllers this week sent commands to the
spacecraft to boost the power in part of the narrow-angle
camera. The vidicon television camera, which long ago began
showing signs of age sooner than its wide-angle companion
camera, needed the added voltage to bring it up to standard
operation and ensure that it returns clear, normal-contrast
images throughout the encounter. "Vidicons do have limited
lifetimes," said assistant project scientist Dr. Ellis Miner,
"but we restricted use of Voyager 2's narrow-angle camera at
Saturn and Uranus to save it for Neptune." The heightened
voltage is just one of many ways the imaging team is able to
maintain the camera's sensitivity when needed, Miner added.
"We still have ways to up its sensitivity before it's no
longer useful."
DISTANCE TO EARTH: 2,717,465,000 miles
DISTANCE TO NEPTUNE: 14,918,000 miles
HELIOCENTRIC VELOCITY: 42,190 mph
====PRESS RETURN TO CONTINUE====
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Current NASA News
0..Previous Menu
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2..NASA Educational Programs
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5..Recent NASA Speeches
6..Shuttle and Other Manifests (Launch Dates)
7..1988 In Review
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9..NASA in the News/NASA Select TV Schedule (Public Affairs Programs)
10.Magellan Status Reports
11.Voyager Status Reports
12.Voyager Neptune Encounter Info
13.STS-28 (Current Shuttle Mission)
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Voyager at Neptune
0..Previous Menu
1..Main Menu
2..Voyager at Neptune & Triton Fact Sheet
3..Neptune Encounter Fact Sheet (1/89)
4..Voyager/Neptune Bulletins
5..NASA Select Programming--Neptune Encounter
6..Neptune Encounter TV Schedule
7..PRESS KIT
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Voyager/Neptune PRESS KIT
0..Previous Menu
1..Main Menu
2..Voyager 2 Encounter of Neptune
3..The Voyager Mission
4..Facts at a Glance
5..Neptune
6..Science Objectives
7..The Science Instruments
8..Voyager 2's Health
9..Mission Operations
10.Telecommunications
11.Voyager Management Team
12.*** All the above in one file ***
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The following document was updated on 08-08-89 and contains 1349 characters.
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FACTS AT A GLANCE
Closest Approaches: August 24, 1989
Times Distance
(at the spacecraft)
Nereid 8:12 p.m. EDT 2,890,000 mi
Ring-plane crossing 11:03 p.m. EDT
(inbound)
Neptune 12 midnight EDT 3,000 mi
August 25, 1989
Ring-plane crossing 1:29 a.m. EDT
(Outbound)
Triton 5:14 a.m. EDT 23,600 mi
One-way light time, Voyager at Neptune to Earth = 4 hours, 6 minutes.
Distance of Voyager 2 from Earth on August 24, 1989: 2,748,802,418 mi
Velocity of Voyager 2 on August 24: Geocentric 90,381 mph
Heliocentric 43,236 mph
Total (arc length) distance Voyager 2 has traveled since launch
at closest approach = 4.4 billion mi.
Total number of images taken at Neptune = 8,000.
General directions of Voyagers after leaving solar system:
Voyager 1 northward to the star AC+79 in Camelopardolis.
Voyager 2 southward to the star Ross 248 in Andromeda.
Launch dates: Voyager 1 September 5, 1977
Voyager 2 August 20, 1977
Cost of Voyager mission as of Neptune Encounter = $556 million
(for both spacecraft not including launch, tracking or data
acquisition).
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VOYAGER 2's HEALTH
The Voyager spacecraft engineering team has learned to cope
creatively with several problems the geriatric machine has
experienced in its long lifetime. Still, the spacecraft and all
of its instruments are in good operating condition.
Malfunctioning Radio
On April 5, 1978, the spacecraft's computer-command
subsystem automatically switched to the back-up receiver. The
back-up at that point had concealed a problem of its own -- a
faulty tracking loop capacitor -- meaning that the receiver could
not hold onto the changing frequency of the transmitted signal.
This required the ground transmitter to send the precise
frequency, taking into account the Doppler shift caused by the
relative motion between the spacecraft and Earth, so that it
would match the frequency that the receiver on the spacecraft was
expecting. That frequency depends on a number of factors,
including the receiver's temperature which fluctuates with
spacecraft activity. When the prime receiver was turned back on,
it failed almost immediately, requiring that the rest of the
mission be flown on the tone-deaf back-up receiver.
Voyager engineers have determined how the tuning depends on
temperature and how the operation of different subsystems onboard
affects the temperature of the receiver. Even so, there is a
period after any change in the spacecraft's configuration when it
is impossible to know the receiver's temperature with adequate
precision. As a result, commands are not routinely transmitted
to Voyager after a change in the spacecraft configuration until
the receiver's temperature has had time to stabilize.
If need be, controllers can send commands to the spacecraft
at different frequencies in rapid succession to ensure that one
will be picked up by the receiver. This and other techniques,
that work around the crippled receiver, were successfully
employed at Jupiter and have been refined further in ensuing
years.
There is always a chance that the backup receiver could fail
or lose contact with Earth permanently. The Voyager team has
planned against this possibility by programming a backup
spacecraft computer with simplified encounter routines for
execution at Neptune. The spacecraft has been instructed to send
data back to Earth even in the event that it loses uplink
contact.
The Stuck Scan Platform
In 1981, Voyager 2's scan platform jammed in one axis just
after its Saturn encounter. The problem limited pointing of the
instruments for the duration of the encounter.
After 2 days, the platform was again movable. Three years
of analysis and testing showed that the problem was due to a loss
of lubricant from overuse at high speeds, which resulted in
damage to a bearing in the high-speed gear train of the
platform. The lubricant apparently migrated back into the gear
train after a short period of rest and the platform was
successfully operated at lower speeds during the Uranus
encounter.
The scan platform continues to be fully operable at lower
speeds and has operated successfully during the cruise to
Neptune. It is expected to operate without problems through the
end of the Neptune encounter.
====PRESS RETURN TO CONTINUE====
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TELECOMMUNICATIONS
The Deep Space Network, operated by the NASA JPL, has
carried out all tracking and communication with the Voyagers
since they left the Earth.
DSN stations are located around the world, in multi-antenna
complexes at Goldstone, in California's Mojave Desert; in
Robledo, near Madrid, Spain; and on the Tidbinbilla Nature
Preserve near Canberra, Australia. The three complexes are
spaced at widely separated longitudes so that spacecraft can be
in continuous view as the Earth rotates.
Each location is equipped with 230-foot antenna (enlarged
from 210 feet); one standard and one high-efficiency 112-foot
antennas; and a 85-foot antenna.
In addition to the antennas, each of the network's signal
processing centers houses equipment for transmission, receiving,
data-handling and interstation communication. The downlink radio
frequency system includes cryogenically-cooled, low-noise
amplifiers.
Uplink
The uplink operates at S-band radio frequency (2,113
megahertz), carrying commands and ranging signals from ground
stations to the spacecraft. The 230-foot antenna stations have
400-kilowatt transmitters. Transmitting power for the standard
112-foot stations is 20 kilowatts.
Downlink
The downlink is transmitted from the spacecraft at S-band
(approximately 2,295 MHz) and X-band (approximately 8,415 MHz)
frequencies. The standard 112-foot antennas and the 230-foot
antennas can receive the S- and X-band signals simultaneously.
The high-efficiency, 112-foot antennas receive only X-band
transmissions.
The signal from Voyager's 20-watt transmitter (about the
same wattage as the light bulb in a refrigerator) gets
progressively fainter as the spacecraft moves farther away. By
the time it reaches Earth, the signal is about 20 billion times
weaker than the battery power that runs an ordinary digital
wristwatch. To track this faint signal, either larger antennas
or more sensitive receivers are needed. In addition, more power
(up to 100 kilowatts for Voyager) is needed to transmit to the
spacecraft across the vast distance.
Shortly after the Voyager 2 Uranus flyby, the three largest
(210 feet in diameter) and most sensitive antennas of the Deep
Space Network were systematically stripped of their surfaces and
rebuilt to create an even larger (230-foot) receiving area for
the incoming signal.
During the Neptune encounter, the 230-foot and 112-foot
antennas at each complex will be arrayed so that their combined
collecting areas will increase the amount of signal captured.
This will improve the potential for high-rate, low-error data
return.
At Canberra, the three DSN antennas will be arrayed with the
210-foot Parkes Radio Astronomy Observatory. The Parkes
facility, operated by the Congress of Scientific and Industrial
Research Organization, is once again critical to spacecraft
support during the Neptune encounter. As during the Uranus
encounter, the high southern (-23 degree) declination of Voyager
2 will result in long, 12-hour periods during which the
spacecraft will be over the Canberra complex and 9 hours over the
Parkes antenna. (The shorter viewing time at Parkes is due to
antenna pointing constraints.) The quality of data received at
the Australian facility also is likely to be higher than that
received in California and Spain because of the large distance
between antennas, which decreases the risk of data loss due to
local weather conditions.
Innovative uses of other, existing equipment, along with the
larger antennas, will significantly increase the potential data
return from Voyager during its last planetary encounter.
In Japan, the 210-foot Usuda Radio Observatory tracking
antenna, owned by the Institute of Space and Astronautical
Science of Japan, will join the Canberra station in collecting
radio science data during the Neptune and Triton radio
occultation experiments.
In the U.S., radio astronomy antennas never before used to
track spacecraft have been accepted into service to track Voyager
at Neptune. The 27 90-foot antennas of the Very Large Array in
Socorro, N.M., operated by Associated Universities, Inc., for the
National Science Foundation, will be arrayed with the Goldstone,
Calif., tracking station.
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Voyager at Neptune
0..Previous Menu
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2..Voyager at Neptune & Triton Fact Sheet
3..Neptune Encounter Fact Sheet (1/89)
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5..NASA Select Programming--Neptune Encounter
6..Neptune Encounter TV Schedule
7..PRESS KIT
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