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Conference 7.286::space

Title:Space Exploration
Notice:Shuttle launch schedules, see Note 6
Moderator:PRAGMA::GRIFFIN
Created:Mon Feb 17 1986
Last Modified:Thu Jun 05 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:974
Total number of notes:18843

391.0. "GALILEO Flight Delays" by ANGORA::PKANDAPPAN () Thu Jan 21 1988 03:10

WHile reading about the Galileo project (and watching the documentary on PBS),
I had few questions:
1. won't components 'age' because of unexpected delays, paritcularly of the
   order of 2-3 years? Won't this jeopardise the mission?
2. Are systems exercised while on the ground (ie. after the system has been
   certified, but has now been put on hold, do they run checks at regular
   intervals to see that nothing has failed)? Doesn't this add to the
   problems in 1.
3. if a particular system was developed (say the Galileo system) and then
   put on hold for a few years; then a new sub-system is desired as an add-on.
   Assuming that this add-on is feasible, is the technology for the sub-system
   restricted to one compatible with the old one (after all it will probably
   be about 6 years old) or will the old one be redesigned? I understand
   the cost and time implications but am looking for examples and/or
   case studies, if possible.
4. In the case of geo-stationary satellites, if the time period for the slot
   alloted to a particular project expires, what is the convention? Does
   one lose the right to the slot or is the allocation renewed?

Thankyou
-parthi
T.RTitleUserPersonal
Name
DateLines
391.1RANGLY::BARNABY_GALEThu Jan 21 1988 08:089
    as far as add-ons, I suspect they try to plan ahead. the voyagers
    were reprogrammed on the fly. looks like they planned ahead on that.
    and since it worked well, they probably looked into that area in
    the design of galileo. when I was at nasa and they put a hold on
    a project, it was mothballed. they also use top line components.
    look how well the voyager and viking probes worked. if the yoyos
    would only build cars that well. but we live in a country of waste.
    disposable razors to disposable cars. all parts have a markup, so
    the more they can make you throw away, the more they make.
391.2Make it fly :== hang it from the ceiling.SNDCSL::SMITHWilliam P.N. (WOOKIE::) SmithThu Jan 21 1988 11:4113
    I would think that they had caught all of the infant failures and
    allowed for redundancies and such, so wearout from aging really
    shouldn't be a factor.  I was under the impression that power supply
    life, and maybe thruster fuel, were the main wearout mechanisms,
    neither of which would come into play until the bird was launched.
    
    Probably the biggest danger is that the schedule is so late that
    the bird will never be launched.  There's a Saturn V being used
    as a lawn ornament at Cape Canaveral, and I'm told the National
    Aerospace museum has a fully functional Skylab that never got off
    the ground.  Heck of an expensive museum piece....
    
    Willie
391.3low probability, but...CRAIG::YANKESThu Jan 21 1988 14:468
    
    	A 300 km flyby of the earth?  Yikes!  Aren't they cutting this
    just a tad close?  I presume this is the first time that a solar
    orbiting body is going to be guided through our satellite field?
    I'd hate to think of the entire project being destroyed due to it
    hitting a piece of space junk left behind in orbit...
    
    							-c
391.4MONSTR::HUGHESThu Jan 21 1988 14:5516
    There is concern that the radioisotope thermal generators will run
    down before mission end. They have a limited life whether you use
    the power they generate or not. The plant that made the fuel elements
    has closed down.
    
    As for the question about geosynch orbits. For comsats, slots are
    assigned to countries by the ITU. Slots include location and frequency
    so you may have multiple birds in one 'location'. The FCC allocates
    from the the pool owned by the US. I believe that you have to show
    progress towards using the slot after a specified time or you lose
    it and have to reapply.
    
    I would think that all geosynch satellites have to go through this,
    but I'm not certain.
    
    gary
391.5Maneuvering thrusters need to be replacedMTWAIN::KLAESN = R*fgfpneflfifaLWed Mar 29 1989 13:3418
Xref: utzoo sci.space:10276 sci.space.shuttle:2728
Newsgroups: sci.space,sci.space.shuttle
Path: utzoo!henry
From: henry@utzoo.uucp (Henry Spencer)
Subject: Space news from January 16 AW&ST
Date: 	Mon, 27 Mar 89 23:50:26 EST
 
    GALILEO's maneuvering thrusters returned to MBB for testing and
modification.  They can overheat, it turns out.  This was discovered
fortuitously during experiments with TVSat 1, the abandoned German
comsat that failed to deploy one solar array - it used similar
thrusters.  GALILEO planners want to see reliable thrusters several
weeks before GALILEO goes to Cape Canaveral, Florida, on May 12,
otherwise the launch schedule will be in trouble. 
 
Welcome to Mars!  Your         |     Henry Spencer at U of Toronto Zoology
passport and visa, comrade?    | uunet!attcan!utzoo!henry henry@zoo.toronto.edu
 
391.6STAR::HUGHESWed Mar 29 1989 15:484
    I think I read that those problems have been fixed (that news item
    dates from early January).
    
    gary
391.7The thrusters were fixedMTWAIN::KLAESN = R*fgfpneflfifaLThu Mar 30 1989 20:3544
Article 10483 of sci.space:
Path: prism!gatech!rutgers!jarvis.csri.toronto.edu!utgpu!utzoo!henry
From: henry@utzoo.uucp (Henry Spencer)
Newsgroups: sci.space,sci.space.shuttle
Subject: Space news from January 23 AW&ST
Message-ID: <1989Mar30.035436.14584@utzoo.uucp>
Date: 30 Mar 89 03:54:36 GMT
Organization: U of Toronto Zoology
Xref: prism sci.space:10483 sci.space.shuttle:2875
 
    Galileo's thrusters are fixed and re-acceptance tests are about to
start. This is on the critical path for launching on time in October. 
About three weeks of margin remain if nothing goes wrong.  The changes
will reduce thruster efficiency about 5%, and may require eliminating
one of the two asteroid flybys or one of the Jovian-satellite
encounters, although there is hope for the full mission.  JPL is very
grateful that they didn't launch in 1986; a workaround for the
thruster problems would probably not have been possible. 

    The problem was discovered during experiments with TVSat 1,
Germany's TV-broadcast satellite that was written off after one solar
array failed to deploy:  it was being used as an operational testbed
when its thrusters failed.  When run nonstop, the thrusters tend to
overheat and destroy themselves.  Worse, there is a "hot start"
problem when pulsing the thrusters, which can ruin the thrusters in
seconds.  MBB is investigating why these problems weren't found during
development.  Minor design differences between Galileo and TVSat 1 may
account for the hot-start problem not showing up on TVSat 1 (or on the
French TDF-1, which has the same thrusters, now being operated in
pulsed mode to avoid the overheating problem). Small plumbing changes
remove the hot-start problem, and changes in mixture ratio and flow
rate remove the overheating problem.  However, the latter set of
changes reduce specific impulse from 280 to 270 s, cutting about 10 kg
off Galileo's fuel reserve.  This is of some concern because the fuel
reserve for Galileo's full mission varied from 50 kg to zero,
depending on what assumptions were made about things like navigational
error and launch date.  If Galileo gets off on time (Oct 12) and
errors are at the 50% level, reserve should be 30-40 kg.  Eliminating
the second asteroid flyby would save about 40 kg, and eliminating one
satellite encounter would save about 15. 
 
Welcome to Mars!  Your         |     Henry Spencer at U of Toronto Zoology
passport and visa, comrade?    | uunet!attcan!utzoo!henry henry@zoo.toronto.edu
  
391.8Thrusters fixed, but use will be very cautiousRENOIR::KLAESN = R*fgfpneflfifaLMon May 15 1989 15:0238
From: henry@utzoo.uucp (Henry Spencer)
Newsgroups: sci.space,sci.space.shuttle
Subject: Space news from April 10 AW&ST
Date: 15 May 89 04:18:14 GMT
Organization: U of Toronto Zoology
 
    Galileo's thrusters have been cleared for flight and are being
reattached, putting Galileo back on schedule for the October launch. 
Unfortunately, there is bad news too:  NASA has decided to restrict
the thrusters to firing only short bursts, out of fear that sustained
operation might damage other nearby thrusters if overheating problems
reappear.  This does not hurt the efficiency of the thrusters, but it
means that major firings take place over longer periods, which *does*
hurt the overall fuel efficiency.  (There are other complications too,
like limits on Galileo's time in preferred thrusting attitudes when in
the near-Sun part of the mission, when solar heating can be a
problem.)  Also, on close inspection, some pulsed-thrust maneuvers
that were in the flight plan already were not examined closely enough,
and they turn out to be more expensive than expected.  Preliminary
estimates, assuming that unpredictable factors are at the 50%
probability level, say that Galileo is about 10 kg short of fuel for
its full mission.  Eliminating one of the two asteroid flybys would
save about 40 kg, and each of the Jovian-moon encounters (10 planned)
costs about 20 kg.  No decision will be made until after Venus
encounter (next Feb), by which time Galileo's actual flight
performance will be known better. 
 
    Actually, only nine of the twelve thrusters tested 100% okay; one
more was rebuilt, the other two have minor problems -- not expected to
endanger the mission -- and are being put in positions where they will
see only light use.  Galileo will go to KSC mid-May and will launch,
it is hoped, Oct 12.  The window is Oct 12 through Nov 24, but fuel
consumption will be minimized with a launch in the first few days. 
The next window is in July 1991. 
 
Subversion, n:  A superset     |     Henry Spencer at U of Toronto Zoology
of a subset.    --J.J. Horning | uunet!attcan!utzoo!henry henry@zoo.toronto.edu

391.9GALILEO Payload Status - May 26RENOIR::KLAESN = R*fgfpneflfifaLFri May 26 1989 19:3549
Newsgroups: sci.space
Subject: Payload Status for 05/26/89 (Forwarded)
Date: 26 May 89 17:16:19 GMT
Reply-To: yee@trident.arc.nasa.gov (Peter E. Yee)
Organization: NASA Ames Research Center, Moffett Field, CA
 
                                   Payload Status Report
                                   Kennedy Space Center
                                   May 26, 1989
 
          George H. Diller
  
          Galileo/IUS-19  (Atlantis)
 
               The Galileo spacecraft left the Jet Propulsion Laboratory in
          Pasadena, California on May 12 and arrived at KSC's SAEF-2
          planetary spacecraft checkout facility at 7:30 p.m. on May 16.
          Galileo and its support equipment were entered through the
          airlock and unloaded on May 17 and 18.  On May 19 Galileo was
          hoisted into a test stand and access platforms were moved into
          position around the spacecraft.  The Galileo probe arrived at KSC
          over a month ago on April 17, and has been in an adjacent SAEF-2
          test cell undergoing final assembly and checkout.  On May 23, it
          was moved into the SAEF-2 high bay with the Galileo orbiter to
          prepare it for integration scheduled for late next week.  This
          will be followed by the final buildup of the spacecraft during
          early June.
 
          Atlas Centaur AC-68/FltSatCom
 
               The AC-68 launch vehicle arrived at the Skid Strip on Cape
          Canaveral Air Force Station at 7:00 a.m. Wednesday, May 24.  It
          was offloaded and taken to Hangar J for receiving inspections.
          On or about Tuesday, May 30 the Atlas will be taken to Pad B at
          Launch Complex 36 for erection.  It will be followed by the
          erection of the Centaur stage approximately two days later.  The
          FltSatCom spacecraft is expected to arrive in mid-June.  The
          launch is expected to occur shortly after Labor Day.
 
          Delta/COBE
 
               The necessary refurbishment of Space Launch Complex 2-West
          at Vandenberg Air Force Base in California is complete.  Assembly
          and checkout of the spacecraft continues at NASA's Goddard
          Spaceflight Center in Greenbelt, Maryland.  The launch of
          Delta/COBE is not expected to occur until at least the end of
          October.  The erection of the booster will begin when a launch
          time frame is determined.

391.10GALILEO Payload Status - June 15RENOIR::KLAESN = R*fgfpneflfifaLThu Jun 15 1989 22:3457
Newsgroups: sci.space
Subject: Payload Status for 06/15/89 (Forwarded)
Date: 15 Jun 89 13:59:27 GMT
Reply-To: yee@trident.arc.nasa.gov (Peter E. Yee)
Organization: NASA Ames Research Center, Moffett Field, CA
 
                                   Payload Status Report
                                   Kennedy Space Center
                                   June 15, 1989
          George Diller
 
          Galileo/IUS-19
 
               Galileo was destacked during the last week of May for
          installation of Central Data System electronics and was followed
          by computer testing.  The umbrella-like high gain antenna, which
          is scheduled for installation at the end of June, underwent a
          deployment test on May 31.  Also that day, the probe was mated to
          the orbiter's despun section.  This section together section with
          the associated retro propulsion module has now been restacked
          with the spun bus.
 
               Electrical testing of individual spacecraft elements has
          been underway over the past week.  On Saturday, June 10, a "stand
          alone" mission sequence test was conducted to electrically verify
          the events which the spacecraft will perform from launch through
          separation from the Inertial Upper Stage.  The IUS will also
          perform this test later in the Vertical Processing Facility.
 
               Yesterday and today, June 14-15, a total of 1300 pounds of
          nitrogen tetroxide oxidizer is being loaded into a pair of
          onboard oxidizer tanks.  Next week the spacecraft will be fueled
          with 800 pounds of hydrazine.
 
               The Inertial Upper Stage is at Cape Canaveral Air Force
          Station.  Electrical testing has been underway on the second
          stage, and a nozzle cone extension test was recently completed.
          Preparations are underway for mating the first and second stage
          late this week.
 
 
          Atlas Centaur AC-68/FltSatCom F-8
 
               The Atlas first stage was erected in the gantry of Pad B on
          Launch Complex 36 on June 6.  The interstage adapter was attached
          on June 7.  The Centaur stage was hoisted into the gantry and
          mated to the Atlas on June 8.  Since that time, electrical
          hookups and attachment of umbilicals have been underway.  The
          work will be completed this week.
 
               A power-up of the booster is scheduled on or about June 22.
          The Terminal Countdown Demonstration (TCD), a tanking of the
          vehicle and simulated countdown, is scheduled for Aug. 9.
 
               The FltSatCom spacecraft is scheduled to arrive at Hangar AM
          on Cape Canaveral Air Force Station on July 31.

391.11GALILEO Payload Status - June 23RENOIR::KLAESN = R*fgfpneflfifaLFri Jun 23 1989 21:1153
Newsgroups: sci.space
Subject: Payload Status for 06/23/89 (Forwarded)
Date: 23 Jun 89 15:50:13 GMT
Reply-To: yee@trident.arc.nasa.gov (Peter E. Yee)
Organization: NASA Ames Research Center, Moffett Field, CA
 
                                   Payload Status Report
                                   Kennedy Space Center
                                   June 23, 1989
 
          George H. Diller
  
          Galileo/IUS-19
 
               In the SAEF-2 planetary spacecraft checkout facility, the
          Galileo spacecraft has been loaded with propellants.  On June 14-
          15, the spacecraft's oxidizer tanks were loaded with approximately 
          1300 pounds of nitrogen tetroxide, and on June 19-20, its fuel 
          tanks were loaded with approximately 800 pounds of hydrazine.  
          The tanks are now being pressurized with helium.  These propellants 
          will be used for spacecraft control during the cruise phase and for 
          mission operations at Jupiter.
 
               The spacecraft is being powered up for further testing.
          Operations are scheduled to resume for the installation of
          pyrotechnic devices next week.  Among the tasks these devices
          perform are deployment of the spacecraft's antennas and instrument 
          booms, removing protective covers, and the probe release.
 
               Other work scheduled next week is a deployment test of the
          umbrella-like high gain antenna, to be followed by its
          installation on the spacecraft.
 
               On IUS-19, the second stage nozzle cone extension tests have
          been sucessfully completed.  Electrical testing of the second
          stage continues.    The IUS is planned to be transported to the
          Vertical Processing Facility on July 23.
 
               Final spacecraft operations and checkout are on schedule
          which will lead to moving the probe to the VPF on July 24.
  
          Atlas Centaur AC-68/FltSatCom F-8
 
               Electrical hook-ups and umbilical connections have been
          completed.  The vehicle was powered up on Tuesday, June 20, to
          begin testing.  Upcoming work includes initial pressurization of
          vehicle systems and series of valve functional tests for the
          Atlas and the Centaur main engines.
 
               The FltSatCom spacecraft is at the TRW plant in Redondo
          Beach, California, being prepared to shipment to the Cape late
          next month.

391.12GALILEO Payload Status - June 30RENOIR::KLAESN = R*fgfpneflfifaLFri Jun 30 1989 22:0372
Newsgroups: sci.space
Subject: Payload Status for 06/30/89 (Forwarded)
Date: 30 Jun 89 17:57:40 GMT
Reply-To: yee@trident.arc.nasa.gov (Peter E. Yee)
Organization: NASA Ames Research Center, Moffett Field, CA
 
                                   Payload Status Report
                                   Kennedy Space Center
                                   Friday, June 30, 1989
  
          George H. Diller
  
          Galileo/IUS-19
 
               In the SAEF-2 planetary spacecraft checkout facility, the S-
          Band/X-band high gain antenna was hoisted atop Galileo on
          Thursday, June 29.  Earlier this week, the installation of 120
          radioisotope heater units was completed.  These are small heat
          devices that keep the science experiments and moveable spacecraft
          elements warm in the very cold environment of deep space.  There
          are 84 on the spacecraft, and 36 on the probe for a total of 120
          RHU's.
 
               Also this week, a stand-alone functional test of the S-
          Band/X-band high gain antenna was conducted.  On Monday, June 26,
          the antenna was deployed.  The following day, a check of antenna
          radio power was conducted.  On Wednesday, June 28, the antenna
          was stowed for flight and prepared for mating with the
          spacecraft.  Today, now that installation on Galileo is complete,
          the antenna will be turned on and the test of radio power
          repeated.  The data will be compared with the earlier results to
          verify that the antenna is properly connected and performing as
          required.  This antenna is used to transmit and receive signals
          between the spacecraft and the Deep Space Network tracking
          stations.
 
               Also scheduled for today is a deployment check of Galileo's
          science boom.  Continuing in work are electrical tests of the
          pyrotechnic devices which have been installed.  These devices are
          associated with boom deployment, removal of optical covers, and
          release of the probe.  Next week, final installation of the
          thermal blankets will begin, and there will be a deployment check
          of the two RTG booms.
 
               The Inertial Upper Stage booster is undergoing checkout on
          Cape Canaveral Air Force Station.  The testing of the avionics
          systems is complete and checkout of the first and second stage
          interfaces will now begin.
 
          SSBUV
 
               On the Shuttle Backscatter Ultraviolet (SSBUV) experiment,
          which will have fixed attachments in the payload bay of Atlantis,
          calibration testing of the experiment has been completed.  The
          flight batteries have been undergoing installation this week.  It
          will be transported from the Hangar AE cleanroom on Cape
          Canaveral Air Force Station to the Orbiter Processing Facility in
          about another week.  It is scheduled for installation in the
          orbiter's payload bay on July 13.
 
          AC-68/FltSatCom F-8
 
               Power-on testing continues.  The nose fairing has arrived
          and has been taken to Hangar J for storage.  The Terminal
          Countdown Demonstration test, the practice countdown which
          includes a complete fueling of the launch vehicle, is scheduled
          for August 9.
 
               The FltSatCom F-8 spacecraft is at the TRW plant in Redondo
          Beach, California, being prepared for shipment.  It will arrive
          at Cape Canaveral on July 31.

391.13GALILEO Payload Status - July 14RENOIR::KLAESN = R*fgfpneflfifaLMon Jul 17 1989 16:56156
Newsgroups: sci.space
Subject: Payload Status for 07/14/89 (Forwarded)
Date: 15 Jul 89 06:34:28 GMT
Reply-To: yee@trident.arc.nasa.gov (Peter E. Yee)
Organization: NASA Ames Research Center, Moffett Field, CA
 
                                     Payload Status Report
                                     Kennedy Space Center
                                     Friday, July 14, 1989
  
          George H. Diller
 
          Galileo/IUS-19
 
               Final prelaunch assembly of the Galileo spacecraft continues
          in the SAEF-2 planetary spacecraft checkout facility.  The low
          gain antenna has been installed and checked out.  Final thermal
          blanket installation continues and is scheduled for completion at
          the end of this week.  The installation of micrometeorite
          shielding is also nearing completion.
 
               The sun gate, acquisition sensor, and star scanner have been
          installed and testing on those instruments is finished.  Testing
          has also been completed on the attitude control sensors.  The
          magnetometer has been installed, connected, and calibrated.
          Deployment tests of the science boom and the pair of RTG booms is
          complete.
 
               A decision has been made to reschedule the installation of
          the radio relay antenna to later at the Vertical Processing
          Facility.  Some additional thermal blanket work is necessary in
          the area of the antenna.  This system is used by the Galileo
          orbiter to receive data from the probe after its deployment.
 
               Earlier this week a test was performed between Galileo and
          the MILA tracking station at KSC.  The exercise attempted to
          determine whether the power and the pair of radio frequencies
          used by MILA could cause spurious commands to be introduced into
          the spacecraft computer.  Such a concern arose on Magellan during
          the launch countdown.  While a low level of radio noise in the
          spacecraft receiver was detected, the test determined that
          inadvertant commands to Galileo's computer is unlikely.
 
               Checkout of the Inertial Upper Stage booster continues on
          Cape Canaveral Air Force Station.  The first and second stage
          have been mated, and this week the booster was attached to the
          aft airborne support equipment.  Electrical testing is now
          underway.  Mating with the forward ASE is scheduled for Monday
          and will also be followed by a series of electrical tests.  The
          IUS will be moved to the Vertical Processing Facility on July 23
          and Galileo's arrival will follow on July 24.  Preparations will
          then begin for IUS/Galileo mating.
  
          SSBUV
 
               Shuttle Solar Backscatter Ultraviolet experiment (SSBUV)
          will provide direct in-orbit data for calibration of ultraviolet
          readings provided by NOAA-9, NOAA 11, and the Ultraviolet
          Atmospheric Research Satellite.  Its primary use relates to the
          long term studies of atmospheric ozone depletion.  This will be
          the first of ten flights for the instrument scheduled between now
          and the end of 1995.
 
               The payload consists of two GAS-type canisters which are
          mounted on an adapter beam in the orbiter.  One canister contains
          the instrument and operates with a motorized door assembly while
          the other canister contains the support systems.
 
               SSBUV is currently in Hangar AE on Cape Canaveral Air Force
          Station and is ready to be transported to the orbiter processing
          facility.  On Tuesday, July 18, it is scheduled to be mounted on
          the right payload bay wall of Atlantis.  On Wednesday, July 19,
          an interface verification test (IVT) will be conducted.
  
          AC-68/FltSatCom F-8
 
               Checkout of the Atlas Centaur on Pad B at Launch Complex 36
          is going well.  Testing of the Atlas stage and Centaur stage
          propulsion systems is underway.  The installation of the vernier
          engine thrusters used in launch vehicle guidance has been
          completed.
 
               The nose fairing has been moved to the ESA-60 explosive safe
          area where it will be prepared for its eventual encapsulation of
          the FltSatCom satellite late in August.  The spacecraft remains
          scheduled to arrive at Cape Canaveral Air Force Station on July
          31 and will be taken to the Hangar AM spacecraft checkout
          facility for final assembly and testing.
 
               Ground facilities and ground support equipment continues
          under test at the launch pad and in the Complex 36 blockhouse.
          There have been no signifcant problems.
 
               The Terminal Countdown Demonstration test - a practice
          countdown, propellant tanking, and launch team certification - is
          scheduled for August 9.
 
               The launch of AC-68 remains targeted for September 8.

Newsgroups: sci.space
Subject: Galileo press briefing scheduled (Forwarded)
Date: 15 Jul 89 06:55:47 GMT
Reply-To: yee@trident.arc.nasa.gov (Peter E. Yee)
Organization: NASA Ames Research Center, Moffett Field, CA
 
Paula Cleggett-Haleim
Headquarters, Washington, D.C.                    July 14, 1989
 
George Diller
Kennedy Space Center, Fla.
 
N89-52
 
    NOTE TO EDITORS:  GALILEO PRESS BRIEFING SCHEDULED
 
     The Galileo planetary spacecraft will be the topic of a press
briefing on Friday, July 21, at the Kennedy Space center, Fla.  A
photo opportunity with the Galileo spacecraft will follow. 
 
     The Galileo briefing will begin at 11:30 a.m. EDT in the KSC News
Center auditorium and will be carried on NASA Select television:
Satcom F2R, transponder 13, 72 degrees west longitude.  Two-way
question and answer capability will be available. 
 
    Participating in the briefing will be:
 
    John Conway, NASA Director of Payload Management and Operations,
Kennedy Space Center 
 
    John Casani, Deputy Assistant Director for Flight Projects,
Jet Propulsion Laboratory, Pasadena, Calif.
 
    Dick Spehalski, Galileo Project Manager, Jet Propulsion Laboratory
 
    Torrence Johnson, Galileo Project Scientist, Jet Propulsion Laboratory
 
    At the conclusion of the press briefing, media representatives
will be transported to the SAEF-2 planetary spacecraft checkout
facility to view Galileo.  All workstands and access platforms have
been removed from around the spacecraft. 
 
     Required clean room attire for members of the press will be
provided.  All photographic equipment must be self contained with
internal power; no external power will be available.  Electronic flash
will be permitted; no flash bulbs may be used.  No flame producing
devices can be permitted in any part of SAEF-2. 
 
     All reporters are asked to refrain from using hair spray and
make-up until after the showing and are requested to wear low-heeled,
closed-toed shoes. 
 
     Because access to Galileo is on a non-interference basis with
spacecraft operations, media representatives may wish to keep in
contact with the Kennedy News Center to be certain that there has been
no change in the date or time of the event. 

391.14Lightning strike at KSCTFH::BAUERWed Sep 13 1989 12:5113
    I saw a picture in the Middlesex news (a Boston Metrowest paper) of
    the space shuttle sitting on the pad with a large bolt of lightning
    striking the pad (next to the base of the right hand SRB).  There
    was no story with the photo.  The caption said:  "Lightning strikes
    near a shuttle vehicle at the Kennedy Space Center in Cape Canaveral
    Fla., where scientists are conducting an ambitious lightning detection
    and protection experiment".  That's all the info they provided.  I
    guess the press figures we don't really care, but it made a nice
    picture.  If this photo is recent, it would mean that the Galleo probe
    is sitting in the cargo bay on the pad.  Does anyone have any more info
    on this?  Was the probe or shuttle damaged?
                                                        
                                             Ron Bauer 
391.15Re: .14PRAGMA::GRIFFINDave GriffinWed Sep 13 1989 14:116
The daily shuttle status reports for the past couple of days did not mention
anything about a lightning strike.  STS-34 looks rather normal from a
launch preparation standpoint.  About the only unusual event was the
replacement of an igniter seal on one of the SRB's.

- dave
391.16Probably No DamageVOSTOK::LEPAGETruth travels slowlyWed Sep 13 1989 14:1412
    Re:.14
    	I believe that the Shuttle that will carry Galileo is already on
    the pad. I'm not too sure, however, whether Galileo and its IUS booster
    are in the cargo bay yet. The capability exists to transfer such
    payloads into the Shuttle while it's on the pad (my geuss is that it is
    in the cargo bay right now though). As far as damage from the pictured
    lightning strike, I haven't heard anything but there is an extensive
    lightning arresting system on and around the Shuttle launch pads making
    lightning damage unlikely.
    
    				Drew
    
391.17LILAC::ZOREI'm the NRA!Tue Sep 19 1989 16:465
My understanding from the news is that hey might pull the shuttle off the 
pad if Hugo gets too close.  Anyone hear anything else about that?  What's 
the top wind speed that the shuttle can sit thru?

Rich
391.1865 mph on pad, 40 mph on transporterCTD016::J_BUTLERLeave it better than you found it...Tue Sep 19 1989 18:2713
    The new report I heard (ABC radio) was that the Shuttle would be
    OK with winds up to 65mph while on the pad. If Hugo threatens landfall
    in the vicinity of Cape Canaveral a decision must be reached much
    earlier since the Shuttle would then have to be moved to the VAB.
    While on the transporter, the Shuttle can only withstand winds up
    to 40mph.
    The reporter also said that the ground crews need 48 hours to conduct
    preparations for the move. He mentioned de-mating, but did not 
    say what would be de-mated. I suspect it would be Galileo and the
    IUS. 
    Is anybody out there familiar with how to remove the Shuttle from
    the pad without launching it?
    John B.
391.19A Lot of (Paper) WorkVOSTOK::LEPAGETruth travels slowlyTue Sep 19 1989 19:2815
    Re:.18
    	Excluding any special handling for the payload (and I am still not
    sure how Galileo and its IUS are being handled), the RCS and APU fuel
    tanks would have to be drained, any test equipment in the shuttle or on
    the pad would have to be removed and stowed, and all the umbilicals
    connecting the fixed facilities (e.g. the service tower) to the mobile
    facilities (e.g. the mobile launch pad and shuttle) would have to be
    disconnected. I also believe that the whole shuttle stack would have to
    be powered down. Once this is all completed (and the mountain of paper
    work to make sure that it has been done) the crawler would be brought
    in, pick up the Shuttle and the mobile pad, and bring it back to the
    VAB which alone takes almost 8 hours.
    
    				Drew
                  
391.20BEATLE::STRANGEOu est le Soleil?Wed Sep 20 1989 01:024
    ... not to mention a significant delay in the launch schedule, at least
    a week I'd guess.
    
    			Steve
391.21The DelayVOSTOK::LEPAGETruth travels slowlyWed Sep 20 1989 13:068
    Re:.20
    	At very least a week. Depending where they are in the processing
    cycle, the delay could be as long as two or three weeks! A delay any
    longer than that could force a scrub of the mission because of
    Galileo's limited launch window.
    
    				Drew
    
391.22Did Galileo launch in time for asteroid flybys?TOLKIN::MCCABEFri Oct 27 1989 13:5571
    
.
.
.

GALILEO MISSION EVENTS


Launch Window (Atlantis and IUS)	Oct. 12 to Nov. 21, 1989

(Note:  for both asteroids, closes in mid-October)

Venus flyby ( 9,300 mi)	*Feb. 9, 1990

Venus data playback	Oct. 1990

Earth 1 flyby ( about 600 mi)	*Dec. 8, 1990

Asteroid Gaspra flyby (600 mi)	*Oct. 29, 1991

Earth 2 flyby (200 mi)	*Dec. 8, 1992

Asteroid Ida flyby (600 mi)	*Aug. 28, 1993

Probe release	July 1995

Jupiter arrival	Dec. 7, 1995

(includes Io flyby, probe entry and relay, Jupiter orbit insertion)

Orbital tour of Galilean satellites	Dec '95-Oct '97


*Exact dates may vary according to actual launch date


.
.
.

FIRST ASTEROID


     Nine months after the Earth passage and still in an elliptical solar orbit,
Galileo will enter the asteroid belt, and two months later, will have its
first asteroid encounter.  Gaspra is believed to be a fairly representative
main-belt asteroid, about 10 miles across and probably similar in
composition to stony meteorites.

     The spacecraft will pass within about 600 miles at a relative speed of
about 18,000 miles per hour.  It will collect several pictures of Gaspra and
make spectral measurements to indicate its composition and physical
properties.


.
.
.

SECOND ASTEROID


     Nine months after the final Earth flyby, Galileo may have a second
asteroid-observing opportunity.  Ida is about 20 miles across.  Like Gaspra,
Ida is believed to represent the majority of main-belt asteroids in
composition, though there are believed to be differences between the two. 
Relative velocity for this flyby will be nearly 28,000 miles per hour, with a
planned closest approach of about 600 miles.


    
391.23It's not too lateVOSTOK::LEPAGETruth travels slowlyFri Oct 27 1989 14:3314
    Re: .22
    	I believe that Galileo was launched in time to reach both asteriods
    provided that the decision to flyby them is made. This decision is
    expected sometime after the Venus flyby in February, 1990. The problem
    at this point is fuel. Based on the expected fuel consumption rates,
    there is a 50% chance that Galileo will be able to flyby the first
    asteriod and still have enough fuel for its primary mission at Jupiter.
    During the cruise to Venus, fuel consumption will be closely monitored.
    If the consumption rate is lower than expected and the trajectory
    correction maneuvers are smaller than planned, at least one and
    possibly both of the asteroids will be observed.
    
    				Drew
    
391.24QuestionsCTD024::TAVARESJohn -- Stay low, keep movingFri Oct 27 1989 19:3614
< Note 391.22 by TOLKIN::MCCABE >
              -< Did Galileo launch in time for asteroid flybys? >-
>Venus flyby ( 9,300 mi)	*Feb. 9, 1990

>Venus data playback	Oct. 1990

Why is there so much time between flyby and playback?

>Asteroid Gaspra flyby (600 mi)	*Oct. 29, 1991

>Asteroid Ida flyby (600 mi)	*Aug. 28, 1993

These are tiny objects (10 and 20 miles) and the probe will be
moving very fast! -- How can get any usable data from them? 
391.25The Playback DelayVOSTOK::LEPAGETruth travels slowlyMon Oct 30 1989 13:0225
    Re:.24
    	The high gain antenna on Galileo is to be left furled behind a sun
    sheild until after its first Earth flyby since the heat from the Sun at
    distances less than Earth's can damage the antenna. Unfortunately, the
    high gain antenna is also Galileo's only means of transmitting at high
    data rates over interplanetary distances. Until after the first Earth
    flyby only a pair of low gain antennas are available for communication.
    At the distance of Venus, the transmission rate will be VERY low (a
    couple of dozen bits per second); so low that it would take about a
    year and a half to transmit all the Venus encounter data. When Galileo
    is closer to the Earth higher transmission rates can be used. By
    October 1990, Galileo will be close enough to the Earth so that the
    data can be played back in a few hours.
    
    	Concerning your other question, trying to observe an asteroid while
    flying past a several miles per second is difficult but possible.
    Voyager was able to obtain sharp pictures and useful data from Neptune
    despite long integration time and exposure times. Galileo's cameras and
    instruments are more sensitive than Voyager's and the light and other
    radiation levels will be much higher in the asteroid belt than they
    were at Neptune. All in all, it is easier for Galileo to observe those
    asteroids than it was for Voyager to observe Neptune.
    
        			Drew
    
391.26Galileo status 10/1/9456821::BATTERSBYSat Oct 01 1994 12:5157
Article: 6499
From: Admin@ccmail.jpl.nasa.gov
Newsgroups: sci.space.news
Subject: Galileo status 10/1/94
Date: 30 Sep 1994 20:55:59 -0700
Organization: Jet Propulsion Laboratory - Pasadena CA
Sender: daemon@news.arc.nasa.gov
 
PUBLIC INFORMATION OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF. 91109. TELEPHONE (818) 354-5011
 
                      GALILEO MISSION STATUS
                          October 1,1994
 
     On Tuesday, September 13, the Jupiter-bound Galileo
spacecraft experienced a failure in one memory cell of an on-
board computer -- one bit out of more than 3 million bits total
in the computer.  This is the only memory failure to have
occurred on Galileo in the 5 years of its flight to date.
 
     During the development of the advanced computer memories, it
was recognized that perhaps dozens of cells would randomly fail
over the 8-year mission lifetime. To protect against such
failures, special fault protection was included in the spacecraft
flight software. Immediately upon detecting the failure on Sept.
13, that fault protection software executed as it was intended
to.  This stopped the sequence of commands then being carried out
to play back science data from Galileo's observation of Comet
Shoemaker-Levy 9 impacts at Jupiter in July, and reconfigured the
spacecraft in a safe state.
 
     By Sept. 25, the failure had been traced and programmed
around, and the transmission of Shoemaker-Levy data resumed. No
long-term mission impacts of the memory failure are expected.
Some of the data lost due to the problem will be recovered by
changing the priorities in a later transmission of data stored on
Galileo's on-board tape recorder.  Transmission of Shoemaker-Levy
data is planned to continue through January 1995.
 
     Currently, data from Galileo's near-infrared mapping
spectrometer of Comet Shoemaker-Levy's fragment G impact are
being transmitted and will be followed later this month by data
from the imaging cameras's observations of the impacts of
fragments K and N.
 
     The spacecraft continues to operate normally, spinning at
about 3 rpm and transmitting at 10 bits per second to ground
stations at NASA/JPL's Deep Space Network. The spacecraft will
reach Jupiter on December 7, 1995, when its probe will descend
into the Jovian atmosphere and the orbiter spacecraft will begin
two years of observation and measurement of the planet, its moons
and magnetosphere.
 
                              #####