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                         *********************


SPACEWARN BULLETIN


   SPX-450           APRIL 25, 1991


                              SPACEWARN Activities
              (All information in this publication was received between
                         March 26 and April 24, 1991.)


A.  List of New International Designations and Launch Dates.  (HQ USSPACECOM 
    Catalog numbers are in parentheses.)


1991-029A  (21230)  COSMOS 2142  Apr 16	1991-025C  (21218)  COSMOS 2141  Apr 04
     028A  (21227)  ASC-2        Apr 13	     025B  (21217)  COSMOS 2140  Apr 04
     027B  (21225)  GRO          Apr 05	     025A  (21216)  COSMOS 2139  Apr 04
     027A  (21224)  STS-37       Apr 05	     024A  (21213)  ALMAZ-1      Mar 31
     026A  (21222)  ANIK E-2     Apr 05	     023A  (21203)  COSMOS 2138  Mar 26


B.  Text of Launching Announcements.

1991-029A  COSMOS 2142 was launched on April 16, 1991, by the U.S.S.R. using a
           COSMOS rocket booster. Initial orbital parameters: period 105 min,
           apogee 1031 km, perigee 983 km, inclination 83 deg.

1991-028A  ASC-2 was launched on April 13, 1991, by the U.S. Initial orbital
           parameters: period 656.1 min, apogee 35,920 km, perigee 1348 km,
           inclination 22.5 deg.

1991-027B  GRO (Gamma Ray Observatory) was deployed from the orbiting STS-37 on
           April 5, 1991.  Initial orbital parameters: period 93.7 min, apogee
           463 km, perigee 449 km, inclination 28.5 deg.

1991-027A  STS-37, the space shuttle ATLANTIS was launched on April 5, 1991 by
           the U.S.  Initial orbital parameters: period 93.8 min, apogee 465 km,
           perigee 449 km, inclination 28.5 deg.

1991-026A  ANIK E-2 was launched on April 5, 1991, by ESA for Canada.  Initial
           orbital parameters: period 1090.7 min, apogee 35,748 km, perigee
           21,693 km, inclination 0.2 deg.

1991-025A  COSMOS 2139,2140,2141 were launched on April 4, 1991, by the U.S.S.R.
 through   using a PROTON rocket booster. The satellites have been put into
1991-025C  approximately circular orbits with the following parameters: period
           676 min, distance from the earths surface 19,148 km, inclination
           64.8 deg.

1991-024A  ALMAZ-1 was launched on March 31, 1991, by the U.S.S.R. using a
           PROTON rocket booster.  The flight program provides for filming of
           the territory of the Soviet Union and other countries in the interest
           of geology, cartography, oceanography, ecology, and agriculture.
           Initial orbital parameters: period 88.7 min, apogee 280 km, perigee 
           170 km, inclination 72.7 deg.

1991-023A  COSMOS 2138 was launched on March 26, 1991, by the U.S.S.R.  Initial
           orbital parameters: period 89.6 min, apogee 369 km, perigee 175 km,
           inclination 67.2 deg.


C.  Spacecraft Particularly Suited for International Participation (Category I).

    1. Spacecraft with essentially continuous radio beacons on frequencies less
than 150 MHz, or higher frequencies if especially suited for ionospheric or
geodetic studies.  ("NNSS" denotes U.S. Navy Navigational Satellite System;
brackets indicate updated information since the last issue.  Spacewarn would
appreciate suggestions to update this list.)

Dessignation,    Epoch, Frequency, Power,
National Name    and Orbit Information      Remarks
-------------    ------------------------   -------

1966-110A        June 16, 1988              Weak signals.  VHF translator
ATS 1            137.35 MHz                 on ~12 hr/day
                 Inclination: 14.0 deg
1967-111A        June 16, 1988              Weak signals
ATS 3            136.37 MHz
                 137.35 MHz
                 Location: 105 deg W
                 Inclination: 12.1 deg
1973-081A        September 15, 1988         Operational transit
OSCAR (NAV) 20   150 MHz at 0.75 W          (Also known as NNSS 30200)
                 400 MHz at 1.25 W
                 Inclination: 89.9 deg
1975-100A        [March 23,1991]
GOES 1           136.38 MHz  
                 [Location: 82.4 deg W]
                 [Inclination: 10.3 deg]
1977-048A        [March 14, 1991]
GOES 2           136.38 MHz
                 [Location: 59.7 deg W]
                 [Inclination: 8.7 deg]
1978-012A        [April 5, 1991]
IUE              136.86 MHz
                 [Inclination: 32.731 deg]
1978-062A        [March 15, 1991]
GOES 3           136.38 MHz
                 [Location: 177.0 deg W]
                 [Inclination: 7.6 deg]
1981-044A        [March 4, 1991             Removed from service 0204Z Mar 3]
NOVA I           150 MHz at 3.00 W          [Switched to maintenance frequency]
                 400 MHz at 5.00 W          [at 2127Z Mar 4]
                 Inclination: 90.0 deg      (Also known as NNSS 30480)
1981-057A        [March 25, 1991]
METEOSAT 2       137.078 MHz
                 [Location: 10.3 deg W]
                 [Inclination: 4.0 deg]
1984-110A        September 15, 1988          Operational transit
NOVA III         150 MHz at 3.00 W           (Also known as NNSS 30500)
                 400 MHz at 5.00 W
                 Inclination: 90.0 deg
1984-114B        [April 1, 1991]
MARECS-B2        137.17 MHz
                 [Location: 55.6 deg W]
                 [Inclination: 2.0 deg]
1984-123A        [April 7, 1991]
NOAA 9           137.62 MHz
                 [Inclination: 99.173 deg]
1985-066B        [February 26, 1991          Switched to maintenance frequency]
OSCAR (NAV) 30   150 MHz at 1.00 W           [and placed in on-orbit storage]
                 400 MHz at 2.00 W           [2048Z Feb 26]
                 Inclination: 89.9 deg       (Also known as NNSS 30300)
1986-073A        [April 7, 1991]
NOAA 10          137.50 MHz
                 [Inclination: 98.572 deg]
1986-088A        September 15, 1988          Experimental
POLAR BEAR       150 MHz at 0.75 W
                 400 MHz at 1.25 W           (Also known as NNSS 30170)
                 Inclination: 89.9 deg
1987-080A        December 5, 1988           Operational transit
OSCAR (NAV) 27   150 MHz at 0.75 W          (Also known as NNSS 30270)
                 400 MHz at 1.25 W
                 Inclination: 90.3 deg
1987-080B        [February 7, 1991          Operational transit]
OSCAR (NAV) 29   150 MHz at 0.75 W          (Also known as NNSS 30290)
                 400 MHz at 1.25 W
                 Inclination: 90.3 deg
1988-033A        January 31, 1989           Operational transit
OSCAR (NAV) 23   150 MHz at 0.75 W          (Also known as NNSS 30230)
                 400 MHz at 1.25 W           
                 Inclination: 90.4 deg         
1988-033B        [February 26, 1991         Operational transit]
OSCAR (NAV) 32   150 MHz at 1.00 W          (Also known as NNSS 30320)
                 400 MHz at 2.00 W
                 Inclination: 90.4 deg
1988-051A        February 7, 1991           Turned-on when beacon of METEOSAT 2
METEOSAT 3       137.080 MHz                is turned off and vice versa
                 Location: 3 deg W
1988-052A        September 15, 1988         Operational transit
NOVA II          150 MHz at 3.00 W          (Also known as NNSS 30490)
                 400 MHz at 5.00 W
                 Inclination: 90.0 deg
1988-074A        September 15, 1988         Stored in orbit at an offset
OSCAR (NAV) 25   150 MHz at 0.75 W          frequency
                 400 MHz at 1.25 W          (Also known as NNSS 30250)
                 Inclination: 90.0 deg       
1988-074B        March 8, 1990              Stored in orbit at an offset
OSCAR (NAV) 31   150 MHz at 1.00 W          frequency
                 400 MHz at 2.00 W          (Also known as NNSS 30130)
                 Inclination: 98.971 deg
1988-089A        [April 9, 1991]
NOAA 11          136.77 MHz
                 137.77 MHz
                 [Inclination: 99.024 deg]

    2. Optical objects used for geophysical studies.  (These objects are also
suitable for studies of air density and atmospheric winds.  Additional research
interest is indicated by + for gravitational fields.  SPACEWARN would appreciate
suggestions to update this list.)


                       + 1965-098C ALOUETTE  2 (rocket)
                         1970-034B CHINA 1     (rocket)
                         1971-016A COSMOS  398
                       + 1984-106A COSMOS 1603
                       + 1988-021B IRS-1A      (rocket)


    3. Satellites useful for simultaneous observation programs with small 
cameras.  ("NNN" Denotes no national name. SPACEWARN should appreciate 
suggestions to update this list.)

                              Apogee   Perigee
                       Incl    (km)     (km)    Magn      Remarks
                       ----   ------   -------  ----      -------

1963-049A  NNN         89.9    1086     1060     +5   cylinder, 4.8 x 1.4 m
1964-001A  NNN         69.9     927      904     +5   cylinder, 8 x 1.5 m
1964-053A  COSMOS 44   65.1     817      608     +4   cylinder
1965-070F  COSMOS      56.1    1515     1357     +5   rocket body
1965-073F  COSMOS      56.1    1686     1387     +5   rocket body
1965-089A  GEOS 1      59.4    2275     1113          octahedron and pyramid,
                                                        0.81 x 1.22 m
1968-002A  GEOS 2     105.8    1570     1082          octahedron and pyramid,
                                                        0.81 x 1.22 m
1975-027A  GEOS 3     115.0     858      818          octahedron and pyramid,
                                                        1.11 x 1.22 m
1976-039A  LAGEOS     109.8    5946     5837          sphere, 0.6 m diameter


    4. Satellite objects that are nearing their decay into the atmosphere.
(Orbital observations of these objects during the decaying phase are useful for
atmospheric studies.  Note: For maneuverable spacecraft the prediction may be
invalid.)

                Objects predicted to decay with 60 days
                ---------------------------------------

                       Expected Decay Dates 1991
                       -------------------------

                            NOT AVAILABLE


    5. Actual Decays.

                          Actual Decay Dates 1991
                          -----------------------

1961-OMI 265                Mar 20	1968-097DX                  Apr 09
1963-047M                   Apr 10	1970-025LJ                  Mar 20
1968-091Z                   Mar 20	1970-025LK                  Mar 28
1970-025LY                  Mar 29	1990-105Q                   Apr 09
1970-025MC                  Apr 01	1990-105X                   Apr 12
1972-058DJ                  Mar 22	1990-105Y                   Apr 12
1980-053A  (MOLNIYA 1-47)   Apr 01	1990-105AC                  Apr 08
1981-053EN                  Mar 25	1990-105AD                  Apr 08
1984-056D                   Apr 14	1991-008A   (COSMOS 2124)   Apr 07
1986-019AX                  Apr 01	1991-011A   (COSMOS 2134)   Apr 01
1986-019JU                  Feb 15	1991-016A   (COSMOS 2136)   Mar 20
1986-019SF                  Mar 26	1991-016F                   Mar 22
1986-019SS                  Apr 01	1991-016H                   Mar 22
1987-020CW                  Mar 28	1991-022B                   Apr 02
1987-020DG                  Mar 30	1991-022C                   Mar 28
1987-036G                   Apr 12	1991-022E                   Mar 29
1989-045B                   Mar 25	1991-023B                   Mar 29
1989-079A   (COSMOS 2046)   Apr 16	1991-024B                   Apr 02
1989-096D                   Apr 15	1991-025D                   Apr 04
1990-096A   (COSMOS 2103)   Apr 03	1991-027A                   Apr 11


D. Launching Reports and Updated Information.

   1. Updated Information

   1991-020A (21188) PROGRESS M-7
        Docked with the orbiting station MIR on March 28, 1991.

   1991-027A (21224) STS-37 
        Landed in California on April 11, 1991


                              CORRECTION
                              ----------

Decay of 1988-038A COSMOS 2033 on January 9, in section C. 5, of SPX-449, the
International ID should read 1989-058A, NOT 1988-038A.
                                        -------------
