Subject: [IGSMAIL-2848] Navstar GPS Constellation Status
From: Richard Langley <[email-masked]>
To: [email-masked]
Date: Sun, 21 May 2000 23:51:21 -0300 (ADT)

******************************************************************************
IGS Electronic Mail      21 May 19:51:30 PDT 2000      Message Number 2848
******************************************************************************

Author: Richard B. Langley

                        Navstar GPS Constellation Status
                                   (00-05-19)

Blk                      NORAD   Orbit   Launch
II       PRN  Internat. Catalog  Plane    Date
Seq  SVN Code    ID      Number  Pos'n    (UT)   Clock Available/Decommissioned
-------------------------------------------------------------------------------
Block I
      01  04  1978-020A  10684          78-02-22        78-03-29     85-07-17
      02  07  1978-047A  10893          78-05-13        78-07-14     81-07-16
      03  06  1978-093A  11054          78-10-06        78-11-13     92-05-18
      04  08  1978-112A  11141          78-12-10        79-01-08     89-10-14
      05  05  1980-011A  11690          80-02-09        80-02-27     83-11-28
      06  09  1980-032A  11783          80-04-26        80-05-16     91-03-06
      07                                81-12-18        Launch failure
      08  11  1983-072A  14189          83-07-14        83-08-10     93-05-04
      09  13  1984-059A  15039          84-06-13        84-07-19     94-06-20
      10  12  1984-097A  15271          84-09-08        84-10-03     95-11-18
      11  03  1985-093A  16129          85-10-09        85-10-30     94-04-13

Block II
II-1  14  14  1989-013A  19802          89-02-14        89-04-15     00-04-14
II-2  13  02  1989-044A  20061    B-3   89-06-10   Cs   89-08-10 20:46 UT
II-3  16  16  1989-064A  20185    E-5   89-08-18   Rb   89-10-14 20:21 UT
II-4  19  19  1989-085A  20302    A-5   89-10-21   Cs   89-11-23 03:13 UT
II-5  17  17  1989-097A  20361    D-3   89-12-11   Cs   90-01-06 03:30 UT
II-6  18  18  1990-008A  20452    F-3   90-01-24   Cs   90-02-14 22:26 UT
II-7  20  20  1990-025A  20533          90-03-26        90-04-18     96-05-10
II-8  21  21  1990-068A  20724    E-2   90-08-02   Cs   90-08-22 15:00 UT
II-9  15  15  1990-088A  20830    D-5   90-10-01   Cs   90-10-15 00:39 UT

Block IIA
II-10 23  23  1990-103A  20959    E-4   90-11-26   Cs   90-12-10 23:45 UT
II-11 24  24  1991-047A  21552    D-1   91-07-04   Rb   91-08-30 04:44 UT
II-12 25  25  1992-009A  21890    A-2   92-02-23   Cs   92-03-24 11:00 UT
II-13 28  28  1992-019A  21930          92-04-10        92-04-25     97-05
II-14 26  26  1992-039A  22014    F-2   92-07-07   Rb   92-07-23 19:43 UT
II-15 27  27  1992-058A  22108    A-4   92-09-09   Cs   92-09-30 20:08 UT
II-16 32  01  1992-079A  22231    F-4   92-11-22   Cs   92-12-11 14:49 UT
II-17 29  29  1992-089A  22275    F-1   92-12-18   Rb   93-01-05 16:39 UT
II-18 22  22  1993-007A  22446    B-1   93-02-03   Rb   93-04-04 05:20 UT
II-19 31  31  1993-017A  22581    C-3   93-03-30   Cs   93-04-13 20:53 UT
II-20 37  07  1993-032A  22657    C-4   93-05-13   Rb   93-06-12 16:15 UT
II-21 39  09  1993-042A  22700    A-1   93-06-26   Cs   93-07-20 12:54 UT
II-22 35  05  1993-054A  22779    B-4   93-08-30   Cs   93-09-28 19:29 UT
II-23 34  04  1993-068A  22877    D-4   93-10-26   Rb   93-11-22 18:20 UT
II-24 36  06  1994-016A  23027    C-1   94-03-10   Cs   94-03-28 14:20 UT
II-25 33  03  1996-019A  23833    C-2   96-03-28   Cs   96-04-09 21:17 UT
II-26 40  10  1996-041A  23953    E-3   96-07-16   Cs   96-08-15 15:05 UT
II-27 30  30  1996-056A  24320    B-2   96-09-12   Cs   96-10-01 15:28 UT
II-28 38  08  1997-067A  25030    A-3   97-11-06   Rb   97-12-18 15:24 UT

Block IIR
IIR-1 42  12                            97-01-17        Launch failure
IIR-2 43  13  1997-035A  24876    F-5   97-07-23   Rb   98-01-31 00:57 UT
IIR-3 46  11  1999-055A  25933    D-2   99-10-07   Rb   00-01-03 15:02 UT
IIR-4 51  20  2000-025A  26360    E-1   00-05-11   Rb

Notes
-----
1.  NORAD Catalog Number is also known as U.S. Space Command (USSPACECOM)
    object number and NASA catalog number.
2.  No orbital plane position = satellite no longer operational.
3.  Clock:  Rb = Rubidium; Cs = Cesium.
4.  Selective Availability (S/A) had been enabled on Block II satellites during
    part of 1990; S/A off between about 10 August 1990 and 1 July 1991 due to
    Gulf crisis; standard level re-implemented on 15 November 1991;
    occasionally off for test and other purposes.  S/A was set to 0 on all 
    satellites by presidential order on 2 May 2000 at approximately 04:00 UT.
5.  Anti-spoofing (A-S) was activated on 31 January 1994 at 00:00 UT on all 
    Block II satellites (ref. NANU 050-94042); occasionally off for test and 
    other purposes.
6.  Decommissioning dates:
    The decommissioning date for PRN06/SVN03 is the date of termination of
    operations of this satellite (ref. USNO) and is about 3 weeks later than
    other published dates for "deactivation".
    PRN14 was set unusable on 26 March 2000 at 23:48 UT and subsequently 
    decommissioned on 14 April 2000 at 13:47 UT (ref. NANUs 2000037 and 
    2000054).
    SVN20/PRN20 had been unusable since 10 May 1996 according to NANU 118-96204
    although it was set usable between 07:36 UT on 20 May 1996 and 22:42 UT on
    21 May 1996 (ref. NANUs 094-96141 and 095-96142). Disposed of on 13
    December 1996 (ref. USNO).
    PRN28 was last usable on 4 November 1996 at 16:34 UT (ref. NANU 179-96309).
    It was declared inoperable in May 1997.  It was removed from the broadcast
    almanacs of all satellites on 15 August 1997.  See Navstar GPS
    Constellation Status report of 6 November 1997 for more information.
7.  PRN number of SVN32 was changed from 32 to 01 on 28 January 1993.
8.  PRN05 and PRN06 are equipped with corner-cube reflectors for satellite
    laser ranging (SLR).  SLR tracking of the satellites will permit onboard
    clock errors and satellite ephemeris errors in GPS tracking to be
    differentiated.
9.  PRN11 (SVN46) was launched on 7 October 1999.  It was set usable on 3 
    January 2000 at 15:02 UT (ref. NANU 2000001).
10. PRN14's active clock was switched from a cesium to a rubidium in a 
    procedure beginning on 26 January 2000 at 01:00 UT.  The procedure was 
    completed on 3 February 2000 at 18:16 UT (ref. NANU 2000023).  PRN14 was 
    subsequently decommissioned (see above).
11. PRN16 has experienced clock problems.  Its active clock was switched from 
    Cesium #4 to Rubidium #1 and then to Rubidium #2 in a procedure beginning 
    on 24 March 2000 at 09:55 UT.  The procedure was completed on 7 April 2000 
    at 21:12 UT (ref. NANU 2000047, GPS Support Center, and USCG).
12. SVN51/PRN20 was launched on 11 May 2000 at 01:48 UT.  It will reside in 
    slot E-1, replacing PRN14.
13. The satellites in planes A and F have been re-phased.  This version of the 
    constellation status table indicates the re-phased slot locations.
14. Compiled by Richard B. Langley, Dept. of Geodesy and Geomatics Engineering,
    University of New Brunswick.
                                                                                
=============================================================================== 
 Richard B. Langley                            E-mail: [email-masked]  
 Geodetic Research Laboratory                  Web: http://www.unb.ca/GGE/
 Dept. of Geodesy and Geomatics Engineering    Phone:    +1 506 453-5142      
 University of New Brunswick                   Fax:      +1 506 453-4943      
 Fredericton, N.B., Canada  E3B 5A3        
     Fredericton?  Where's that?  See: http://www.city.fredericton.nb.ca/
===============================================================================