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Jonathan's Space Report, No. 405

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  • Frits Westra
    Jonathan s Space Report No. 405 1999 Aug 4 Cambridge, MA
    Message 1 of 1 , Aug 5, 1999
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      Jonathan's Space Report
      No. 405 1999 Aug 4 Cambridge, MA


      I don't often editorialize like this, but I'll make an exception. Even
      with the restoration of funding for the crucial SIRTF mission on Friday,
      the proposed NASA budget cuts are a devastating blow to the US space
      science program and to the morale of all of us who work on NASA
      programs. The Discovery and Explorer programs are badly hit, US
      participation in Solar B and FIRST/Planck would be cut, and the GLAST
      gamma ray telescope might face the axe. NASA's budget in real terms has
      been cut repeatedly in recent years. The new cuts to space science are
      especially harsh, given the major successful reforms of the NASA space
      science program. We've worked hard over the past decade to bring the US
      public great results from our studies of the universe while cutting back
      budgets. I frequently give talks to the general public and have been
      aware of a growing enthusiasm for, interest in, and support for space
      science over the past few years. I hope the US public will become aware
      of the proposed cuts and persuade Congress to relent further.


      Chandra continues to operate well in transfer orbit. Both the ACIS and
      HRC cameras have survived launch and will be checked out over the next
      few weeks. The IPS-3 burn to raise apogee to 140000 km was carried out
      at 2232 UTC on Jul 31. DSN tracking indicates the orbit is now 3482 x
      139384 km x 28.5 deg. A further IPS-4 burn on Aug 4 raised perigee to
      around 5700 km, and another perigee raise burn is planned for Aug 7.

      The Integral Propulsion System on Chandra uses four TR-308 bipropellant
      thrusters for orbit changes. The thrusters use N2O4 (nitrogen tetroxide)
      oxidizer and N2H4 (hydrazine) fuel. They have a thrust of 472N and a
      specific impulse of 322.3s; the TR-308 is an upgrade of the TR-306 that
      was used on three Lockheed Martin Series 5000 satellites. The same fuel
      tanks also feed Marquardt 89N monopropellant hydrazine RCS thrusters. In
      addition to the IPS, the MUPS (Momentum Unloading Propulsion System)
      uses 0.9N hydrazine thrusters to unload momentum from the gyro systems
      used to point Chandra. (Thanks to the TRW propulsion experts for the
      info). Thrusters LAE-1 and LAE-3 were used for the first three burns;
      LAE-2 and LAE-4 were used for IPS-4 and will be used for the remaining

      Columbia landed at 0320 UTC on Jul 28 on runway 33 at KSC. Post flight
      inspection confirms the presence of holes in the cooling lines on the
      nozzle of SSME 2019 (engine 3) which caused a hydrogen leak. A loose
      repair pin in the engine broke free and may have caused the failure.
      Although the leak was small, this combined with the electrical short
      makes two semi-serious failures in the main propulsion system during
      ascent, and I can't remember a launch since 51-L when we've had that.
      Fortunately the two failures didn't add together, but it seems like we
      lost enough redundancy to make me nervous.

      Recent Launches

      Deep Space 1 made a flyby of minor planet (9969) Braille at 0446 UTC on
      Jul 29. Flyby distance was less than 25 km and possibly as little as 15
      km. DS 1 failed to point its camera to image the target at closest
      approach, but the navigation system was successful in bringing the
      vehicle close to the asteroid, and longer range IR imaging was
      successful. The NSTAR ion engine continues to operate well.

      Lunar Prospector impacted the lunar surface at 0952 UTC on 1999 Jul 31.
      Impact site was 42.1E, 87.7S near the lunar south pole. The orbit was
      raised to a 230 km apogee before the deorbit burn over the lunar farside
      at 0919 UTC.

      Table of Recent Launches
      Date UT Name Launch Vehicle Site Mission INTL.

      Jun 5 0721 Starshine - OV-103, LEO Education 30B
      Jun 10 1348 Globalstar 52) Delta 7420-10 Canaveral SLC17B Comsat 31A
      Globalstar 49) 31B
      Globalstar 25) 31C
      Globalstar 47) 31D
      Jun 11 1715 Iridium 14A ) CZ-2C/SD Taiyuan Comsat 32A
      Iridium 21A ) Comsat 32B
      Jun 18 0149 Astra 1H Proton-K/DM3 Baykonur LC81L Comsat 33A
      Jun 20 0215 QuikScat Titan 23G Vandenberg SLC4W R/Sensing 34A
      Jun 24 1544 FUSE Delta 7320-10 Canaveral SLC17A Astronomy 35A
      Jul 5 1332 Raduga Proton-K/BrizM Baykonur LC81P Comsat F02
      Jul 8 0846 Molniya-3 Molniya-M Plesetsk Comsat 36A
      Jul 10 0845 Globalstar 32) Delta 7420-10 Canaveral SLC17B Comsat 37A
      Globalstar 30) Comsat 37B
      Globalstar 35) Comsat 37C
      Globalstar 51) Comsat 37D
      Jul 16 1636 Progress M-42 Soyuz-U Baykonur LC1 Cargo 38A
      Jul 17 0638 Okean-O Zenit-2 Baykonur LC45 R/Sensing 39A
      Jul 23 0428 Columbia Shuttle Kennedy LC39B Spaceship 40A
      Jul 23 1147 Chandra IUS OV-102, LEO Astronomy 40B
      Jul 25 0746 Globalstar 26) Delta 7420 Canaveral SLC17A Comsat 41A
      Globalstar 28) Comsat 41B
      Globalstar 43) Comsat 41C
      Globalstar 48) Comsat 41D

      Current Shuttle Processing Status

      Orbiters Location Mission Launch Due

      OV-102 Columbia OPF Bay 3 OMDP
      OV-103 Discovery OPF Bay 1 STS-103 Oct 14
      OV-104 Atlantis VAB Bay 2 STS-101 Dec 2
      OV-105 Endeavour OPF Bay 2 STS-99 Sep 18

      MLP1/ LC39B STS-93
      MLP3/RSRM-71?/ET? VAB Bay 3 STS-99

      | Jonathan McDowell | phone : (617) 495-7176 |
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