** Updated 29 June 2020 **
Latest changes (see below for earlier changes):
(30 May 2020): Iridium 96 (27376, 2002-005E) decayed on 30 May 2020.
Summary of current Iridium constellation status:
Iridium Next:
75 satellites have so far been launched , and all
orbital planes are now complete.
6 further satellites (Iridiums 174, 177, 178, 179, 181 and 182)
remain as on ground spares.
On 24 June 2020, Relativity Space announced that it had signed a
contract with Iridium for up to 6 launches of the on ground spare
satellites as needed between 2023 and 2030.
Original Iridium:
A total of 95 satellites were launched; none now remain
operational.
- 65 satellites have been de-orbited (retired) following
replacement by Iridium Next in 2017, 2018 and 2019. 61 out of
these have so far re-entered (decayed). It may be many months
before the rest decay.
- 25 satellites failed on-orbit and can no longer be controlled.
It will be many years before the last of these decay.
- 3 satellites rentered between 2000 and 2002 after failing to
reach operational orbit.
- 2 failed satellites were deliberately deorbited in 2001 and
2003.
For a summary of the Iridium launch sequence, see my Iridium Launch Chronology. There is now also a summary of Iridium Failures.
Note that the Iridium Next satellites are not expected to produce flares from the Main Mission Antenna in the same way as the original Iridium satellites.
Orbital <----------------------- Operational satellites ------------------------> Spares
Plane
Plane 1: 145 143 140 148 150 153 144 149 146 142 157 124 Note that Iridium 153 was migrated from Plane 2 to Plane 1.
Note that Iridium 124 was migrated from Plane 3 to Plane 1.
Plane 2: 134 141 137 116 135 151 120 113 138 130 131 115 Note that Iridiums 113 and 120 were migrated from Plane 3 to Plane 2. Iridium 115 was also migrated from Plane 3 to Plane 2.
Plane 3: 117 168 180 123 126 167 171 121 118 172 173 175 176 170
Plane 4: 119 122 128 107 132 129 127 133 125 136 139 169 Note that Iridium 128 was migrated from Plane 3 to Plane 4.
Note that Iridium 169 was migrated from Plane 3 to Plane 4.
Plane 5: 158 160 159 163 165 166 154 105/164 108 155 156 Note that Iridiums 108 and 105 were migrated from Plane 6 to Plane 5.
Plane 6: 102 112 104 114 103 109 106 152 147 110 111 162 161
Original <----------- Failed ------------> <--- Retired ---> <-------------------- Failed or retired ---------------------> Note that some of the failed satellites have drifted from the original orbital planes Orbital (but still in orbit) (still in orbit) (decayed) Plane Plane 1: 73t 63 74d 72d 21d 68d 67d 75d 65d 66d 70d 62d 14d 64d (Iridium 74 deliberately de-orbited. It was probably already a partial failure. Iridium 72, Iridium 21, Iridium 68, Iridium 67, Iridium 75, Iridium 65, Iridium 66, Iridium 70, Iridium 62, Iridium 14 and Iridium 64 deliberately de-orbited.) Plane 2: 69t 24t 71t 26 22 48d 3d 49d 23d 94d 25d 76d 47d 20d 11d 46d (Iridium 48, Iridium 3, Iridium 49, Iridium 46, Iridium 23, Iridium 94, Iridium 25, Iridium 47, Iridium 11 and Iridium 20 deliberately de-orbited.) Plane 3: 28 29 33t 57 45 27d 30d 31d 32d 59d 91d 60d 95d 55d 58d (Iridium 30, Iridium 31, Iridium 32, Iridium 91, Iridium 59, Iridium 60, Iridium 95, Iridium 55, Iridium 58 and Iridium 45 deliberately de-orbited.) Plane 4: 4 36t 7 51 5 8d 6d 34d 19d 37d 35d 61d 97d 96d (Iridium 8, Iridium 51, Iridium 5, Iridium 6, Iridium 19, Iridium 34, Iridium 96, Iridium 37, Iridium 35, Iridium 61 and Iridium 97 deliberately de-orbited. Iridium 7, Iridium 51 and Iridium 6 were probably already partial failures.) Plane 5: 2t 914t 911t 16t 85d 9d 13d 12d 50d 53d 86d 10d 56d 52d 84d 83d 90d 54d (Iridium 9, Iridium 90, Iridium 13, Iridium 12, Iridium 86, Iridium 56, Iridium 50, Iridium 84, Iridium 53, Iridium 10, Iridium 83 and Iridium 52 deliberately de-orbited.) Iridium 2 has drifted far from its original launch plane, and continues to drift Plane 6: 920t 921t 44t 38t 17t 42t 39 82 79d 77d 43d 81d 41d 80d 18d 98d 40d 15d (Iridium 40, Iridium 82, Iridium 43, Iridium 77, Iridium 18, Iridium 81, Iridium 41, Iridium 98, Iridium 80 and Iridium 15 deliberately de-orbited.)
t indicates satellites that have been reported as tumbling out of control.
Notes:
This is Rod Sladen's personal opinion of the status of the Iridium constellation, and the information herein has not been confirmed by the new owners, Iridium Satellite LLC, nor by Boeing who are maintaining the system for them.
Iridium 11 (at one time referred to by OIG as Iridium 20), Iridium 14, Iridium 20 (at one time referred to by OIG as Iridium 11) and Iridium 21 are the second (i.e. replacement) satellites known by those names. They were previously known as Iridium 20a, Iridium 14a, Iridium 11a and Iridium 21a respectively.
Iridium 911, Iridium 914, Iridium 920, Iridium 921 are the (failed) satellites originally known as Iridium 11, Iridium 14, Iridium 20 and Iridium 21 respectively.
d indicates satellites that have already decayed:
Iridium 79 (25470, 1998-051D) decayed on 29 November 2000
(see http://www.satobs.org/seesat/Nov-2000/0256.html),
Iridium 85 (25529, 1998-066C) decayed on 30 December 2000
(see http://www.satobs.org/seesat/Dec-2000/0409.html),
Iridium 48 (25107, 1997-082D) decayed on 5 May 2001
(see http://www.satobs.org/seesat/May-2001/0028.html),
and
Iridium 27 (24947, 1997-051D) decayed on 1 February 2002
(see http://www.satobs.org/seesat/Feb-2002/0002.html)
Iridium 9 (24838, 1997-030C) decayed on 11 March 2003
(see http://www.satobs.org/seesat/Mar-2003/0116.html)
Iridium 5 and Iridium 51 were confused during August 2001.
Note that the identities of various members of the Iridium
constellation have been confused at various times in the past.
Some interchanges of identities seems to have become permanent:
Iridium 24 is tumbling, and correctly labelled by Spacecom as
Iridium 24, and correctly tracked, but under 25105 (1997-082B)
which are the catalog number and launch identifier which
originally belonged to Iridium 46.
Iridium 46 remained operational, correctly labelled by Spacecom
as Iridium 46, and correctly tracked, but under 24905 (1997-043C)
which are the catalog number and launch identifier which
originally belonged to Iridium 24.
Iridium 11 was operational, and correctly labelled by Spacecom as
Iridium 11, and correctly tracked, but under 25578 (1998-074B)
which are the catalog number and launch identifier which
originally belonged to (the second) Iridium 20.
Iridium 20 was operational, and correctly labelled by Spacecom as
Iridium 20, and correctly tracked, but under 25577 (1998-074A)
which are the catalog number and launch identifier which
originally belonged to (the second) Iridium 11.
(27 December 2019): Iridium 97 (27450,
2002-031A) decayed on 27 December 2019.
(05 December 2019): The process of de-orbiting Iridium 97
(27450, 2002-031A) has started.
(mid November 2019): Iridium 169 (43926,
2019-002E) has completed its migration from Plane 3 to Plane 4
and is now the spare in Plane 4, replacing Iridium 97
(23 July 2019): Iridium 61 (25263,
1998-018B) decayed on 23 July 2019.
(21 June 2019): The process of de-orbiting Iridium 61
(25263, 1998-018B) has started.
(11 May 2019): Iridium 46 (tracked as
24905, 1997-043C) decayed on 11 May 2019.
(11 May 2019): Iridium 54 (25171, 1998-010C)
decayed on 11 May 2019.
(16 April 2019): The process of de-orbiting Iridium 54
(25171, 1998-010C) has started.
(07 April 2019): Iridium 58 (25274, 1998-019C) decayed on
07 April 2019.
(01 April 2019): Iridium 64 (25287, 1998-021C)
decayed on 01 April 2019.
(31 March 2019): Iridium 55 (25272, 1998-019A)
decayed on 31 March 2019.
(28 March 2019): The process of de-orbiting
Iridium 45 (25104, 1997-082A) has started.
(25 March 2019): Iridium 95 (27375, 2005-005D)
decayed on 25 March 2019.
(21 March 2019): The process of de-orbiting
Iridium 58 (25274, 1998-019C) has started.
(17 March 2019): Iridium 60 (25276, 1998-019E)
decayed on 17 March 2019.
(15 March 2019): The process of de-orbiting
Iridium 64 (25287, 1998-021C) has started.
(15 March 2019): Iridium 14 (25777, 1999-032A)
decayed on 15 March 2019.
(13 March 2019): The process of de-orbiting
Iridium 55 (25272, 1998-019A) has started.
(13 March 2019): Iridium 91 (27372, 2005-005A)
decayed on 13 March 2019.
(11 March 2019): Iridium 59 (25275, 1998-019D)
decayed on 11 March 2019.
(10 March 2019): Iridium 32 (24945, 1997-051B)
decayed on 10 March 2019.
(07 March 2019): The process of de-orbiting
Iridium 95 (27375, 2005-005D) has started.
(01 March 2019): The process of de-orbiting
Iridium 60 (25276, 1998-019E) has started.
(27 February 2019): The process of de-orbiting
Iridium 14 (25777, 1999-032A) has started.
(22 February 2019): The process of de-orbiting
Iridium 59 (25275, 1998-019D) has started.
(15 February 2019): The process of de-orbiting
Iridium 91 (27372, 2005-005A) has started.
(08 February 2019): The process of de-orbiting
Iridium 32 (24945, 1997-051B) has started.
Iridium 175 (43928, 2019-002G), Iridium 176
(43923, 2019-002B) and Iridium 170 (43930, 2019-002J) have had
their orbits raised slightly, and are evidently to remain as
spares in orbital plane 3.
(02 February 2019): Iridium 169 (43926, 2019-002E) has started
migrating from Orbital Plane 3 towards Orbital Plane 4.
(06 February 2019): Iridium 168 and Iridium 180 are reported as
having entered service, completing the Iridium Next
constellation.
(-- February 2019): Iridium 180 (43922, 2019-002A) has entered
the operational constellation at Plane 3, Slot 3, a few seconds
behind Iridium 45 (25104, 1997-082A).
(31 January 2019): Iridium 168 (43924, 2019-002C) has entered the
operational constellation at Plane 3, Slot 2, a few seconds
behind Iridium 95 (27375, 2002-005D).
(01 February 2019): Iridium 172 and Iridium 173 are reported as
having entered service on 01 February 2019.
(29 January 2019): Iridium 173 (43925, 2019-002D) has entered the
operational constellation at Plane 3, Slot 11, a few seconds
behind Iridium 60 (25276, 1998-019E).
(-- January 2019): Iridium 172 (43927, 2019-002F) has entered the
operational constellation at Plane 3, Slot 10, a few seconds
behind Iridium 59 (25275, 1998-019D).
(28 January 2019): Iridium 167 and Iridium 171 are reported as
having entered service on 28 January 2019.
(26 January 2019): Iridium 171 (43929, 2019-002H) has entered the
operational constellation at Plane 3, Slot 7, a few seconds
behind Iridium 91 (27372, 2005-005A).
(24 January 2019): Iridium 167 (43931, 2019-002K) has entered the
operational constellation at Plane 3, Slot 6, a few seconds
behind Iridium 32 (24945, 1997-051B).
(23 January 2019): Iridium 90 (27373, 2002-005B) decayed on 23 January 2019.
The eighth Iridium Next launch took place
on 11 January 2019 and was directed towards orbital plane 3. This
included Iridiums 167, 168, 169, 170, 171, 172, 173, 175, 176 and
180.
Some of the satellites will be used to complete orbital plane 3,
while others will be moved to become spares for adjacent orbital
planes.
(28 December 2018): Iridium 124 (42810, 2017-039H) completed migration from Orbital plane 3 to Orbital Plane 1, and its orbit was raised. It will presumably be a spare for Orbital Plane 1.
(26 December 2018): Iridium 35 (24966,
1997-056B) decayed on 26 December 2018.
(20 December 2018): Iridium 31 (24950,
1997-051G) decayed on 20 December 2018.
(06 December 2018): The process of de-orbiting
Iridium 35 (24966, 1997-056B) has started.
(30 November 2018): The process of de-orbiting
Iridium 31 (24950, 1997-051G) has started.
(07 November 2018): Iridium 62 (25285,
1998-021A) decayed on 07 November 2018.
(05 November 2018): Iridium 52 (25169,
1998-010A) decayed on 05 November 2018.
(05 November 2018): Iridium 83 (25531,
1998-066E) decayed on 05 November 2018.
(04 November 2018): Iridium 84 (25530,
1998-066D) decayed on 04 November 2018.
(22 October 2018): Iridium 11 (25578, 1998-074B)
decayed on 22 October 2018.
(22 October 2018): Iridium 20 (25577, 1998-074A)
decayed on 22 October 2018.
(19 October 2018): The process of de-orbiting
Iridium 62 (25285, 1998-021A) has started.
(17 October 2018): The process of de-orbiting
Iridium 52 (25169, 1998-010A) has started.
(14 October 2018): Iridium 15 (24869, 1997-034A)
decayed on 14 October 2018.
(11 October 2018): The process of de-orbiting
Iridium 83 (25531, 1998-066E) has started.
(11 October 2018): Iridium 56 (25170, 1998-010B)
decayed on 11 October 2018.
(11 October 2018): Iridium 70 (25342, 1998-032A)
decayed on 11 October 2018.
(06 October 2018): Iridium 10 (24839, 1997-030D)
decayed on 06 October 2018.
(05 October 2018): Iridium 86 (25528, 1998-066B)
decayed on 05 October 2018.
(05 October 2018): The process of de-orbiting
Iridium 20 (25577, 1998-074A) has started.
(03 October 2018): The process of de-orbiting
Iridium 11 (25578, 1998-074B) has started.
(30 September 2018): Iridium 53 (25173,
1998-010E) decayed on 30 September 2018.
(28 September 2018): The process of de-orbiting
Iridium 15 (24869, 1997-034A) has started.
(24 September 2018): The orbit of Iridium 14 (25777,
1999-032A) has been lowered by 15km and it is presumably being
retained as a spare for plane 1.
(23 September 2018): Iridium 40 (25041,
1997-069C) decayed on 23 September 2018.
(23 September 2018): Iridium 50 (25172,
1998-010D) decayed on 23 September 2018.
(20 September 2018): The process of de-orbiting
Iridium 70 (25342, 1998-032A) has started.
(15 September 2018): The orbit of Iridium 52 (25169,
1998-010A) has been lowered by 15km and it is presumably being
retained as a spare for plane 5.
(14 September 2018): The process of de-orbiting
Iridium 10 (24839, 1997-030D) has started.
(13 September 2018): The process of de-orbiting
Iridium 53 (25173, 1998-010E) has started.
(09 September 2018): The orbit of Iridium 54 (25171,
1998-010C) has been lowered by 15km and it is presumably being
retained as a spare for plane 5.
(07 September 2018): The process of de-orbiting
Iridium 84 (25530, 1998-066D) has started.
(04 September 2018): Iridium 153 (43078, 2017-083J) has
completed migration from orbital plane 2 to orbital plane 1,
and has entered the operational constellation at Plane 1, Slot 6,
a few seconds behind Iridium 14 (25777, 1999-032A)
(02 September 2018): Iridium 12 (24837, 1997-030B)
decayed on 02 September 2018.
(01 September 2018): Iridium 47 (25106,
1997-082C) decayed on 01 September 2018.
(01 September 2018): The process of de-orbiting
Iridium 50 (25172, 1998-010D) has started.
(28 August 2018): Iridium 76 (25432, 1998-048B)
decayed on 28 August 2018.
(27 August 2018): Iridium 164 (43577, 2018-061J) has
entered the operational constellation at Plane 5, Slot 8, a few
seconds behind Iridium 105 (41921, 2017-003E)!
(24 August 2018): Iridium 98 (27451, 2002-031B) decayed
on 24 August 2018.
(24 August 2018): Iridium 154 (43574, 2018-061F) has
entered the operational constellation at Plane 5, Slot 7, a few
seconds behind Iridium 54 (25171, 1998-010C).
(24 August 2018): The process of de-orbiting Iridium 56
(25170, 1998-010B) has started.
(23 August 2018): Iridium 66 (25289, 1998-021E)
decayed on 23 August 2018.
(22 August 2018): The process of de-orbiting
Iridium 86 (25528, 1998-066B) has started.
(22 August 2018): Iridium 166 (43570, 2018-061B) has
entered the operational constellation at Plane 5, Slot 6, a few
seconds behind Iridium 10 (24839, 1997-030D).
(19 August 2018): Iridium 18 (24872, 1997-034D) decayed
on 19 August 2018.
(18 August 2018): Iridium 165 (43572, 2018-061D) has
entered the operational constellation at Plane 5, Slot 5, a few
seconds behind Iridium 84 (25530, 1998-066D).
(18 August 2018): Iridium 163 (43575, 2018-061G) has entered the
operational constellation at Plane 5, Slot 4, a few seconds
behind Iridium 53 (25173, 1998-010E).
(17 August 2018): The process of de-orbiting Iridium 47
(25106, 1997-082C) has started.
(16 August 2018): Iridium 159 (43578, 2018-061K) has
entered the operational constellation at Plane 5, Slot 3, a few
seconds behind Iridium 52 (25169, 1998-010A).
(15 August 2018): The process of de-orbiting Iridium 12
(24837, 1997-030B) has started.
(13 August 2018): Iridium 160 (43569, 2018-061A) has entered the
operational constellation at Plane 5, Slot 2, a few seconds
behind Iridium 56 (25170, 1998-010B).
(12 August 2018): Iridium 158 (43571, 2018-061C) has entered the
operational constellation at Plane 5, Slot 1, a few seconds
behind Iridium 50 (25172, 1998-010D).
(12 August 2018): Iridium 80 (25469, 1998-051C) decayed
on 12 August 2018.
(10 August 2018): Iridium 156 (43576, 2018-061H) has
entered the operational constellation at Plane 5, Slot 11, a few
seconds behind Iridium 86 (25528, 1998-066B).
(09 August 2018): The process of de-orbiting Iridium 76
(25432, 1998-048B) has started.
(09 August 2018): Iridium 155 (43573, 2018-061E) has
entered the operational constellation at Plane 5, Slot 10, a few
seconds behind Iridium 83 (25531, 1998-066E).
(02 August 2018): The process of de-orbiting Iridium 66
(25289, 1998-021E) has started.
(28 July 2018): Iridium 41 (25040, 1997-069B)
decayed on 28 July 2018.
(25 July 2018): The seventh Iridium Next launch took place on 25 July 2018 and was directed towards orbital plane 5. It included Iridiums 154, 155, 156, 158, 159, 160, 163, 164, 165 and 166.
(19 July 2018): Iridium 65 (25288, 1998-021D) decayed on 19 July 2018
(17 July 2018): Iridium 81 (25468, 1998-051B) decayed on 17 July 2018
(12 July 2018): The process of de-orbiting Iridium 80 (25469, 1998-051C) has started.
(10 July 2018): Iridium 75 (25346, 1998-032B) decayed on 10 July 2018
(07 July 2018): The process of de-orbiting Iridium 98 (27451, 2002-031B) has started.
(02 July 2018): Iridium 67 (25290, 1998-021F) decayed on 02 July 2018
(28 June 2018): The process of de-orbiting Iridium 65 (25288, 1998-021D) has started.
(21 June 2018): The process of de-orbiting Iridium 41 (25040, 1997-069B) has started.
(15 June 2018): The process of de-orbiting Iridium 75 (25346, 1998-032B) has started.
(14 June 2018): Iridium 152 (43479, 2018-047D) has entered the operational constellation at Plane 6, Slot 8, a few seconds behind Iridium 80 (25469, 1998-051C).
(13 June 2018): The process of de-orbiting Iridium 81 (25468, 1998-051B) has started.
(12 June 2018): The orbit of Iridium 70 (25342, 1998-032A) has been lowered by 15km and it is presumably being retained as a spare for plane 1.
(10 June 2018): Iridium 147 (43480, 2018-047E)
has entered the operational constellation at Plane 6, Slot 9, a
few seconds behind Iridium 98 (27451, 2002-031B).
(09 June 2018): Iridium 110 (43481, 2018-047F) has entered the
operational constellation at Plane 6, Slot 10, a few seconds
behind Iridium 41 (25040, 1997-069B).
(08 June 2018): The process of de-orbiting Iridium 67 (25290, 1998-021F) has started.
(06 June 2018): Iridium 68 (25291, 1998-021G) decayed on 06 June 2018
(05 June 2018): Iridium 115 (42806, 2017-039D) has completed migration from Orbital Plane 3 to Orbital Plane 2, and will presumably be kept as on-orbit spare for Orbital Plane 2.
(01 June 2018): The process of de-orbiting Iridium 18 (24872, 1997-034D) has started.
(26 May 2018): Iridium 37 (24968,
1997-056D) decayed on 26 May 2018
(24 May 2018): Iridium 21 (25778, 1999-032B)
decayed on 24 May 2018
(22 May 2018): The sixth Iridium Next launch took place on 22 May 2018 and was directed towards orbital plane 6. It included Iridiums 110, 147, 152, 161 and 162.
(14 May 2018): Iridium 25 (24904,
1997-043B) decayed on 14 May 2018
(14 May 2018): Iridium 72 (25343, 1998-032B)
decayed on 14 May 2018
(14 May 2018): The orbit of Iridium 62 (25285,
1998-021A) has been lowered by 15km and it is presumably being
retained as a spare for plane 2.
(12 May 2018): The orbit of Iridium 64 (25287, 1998-021C) has
been lowered by 15km and it is presumably being retained as a
spare for plane 2.
(12 May 2018): The orbit of Iridium 66 (25289, 1998-021E) has
been lowered by 15km and it is presumably being retained as a
spare for plane 2.
(10 May 2018): The process of de-orbiting Iridium 68 (25291, 1998-021G) has started.
(07 May 2018): Iridium 140 (43252, 2018-030D) has entered the operational constellation at Plane 1, Slot 3, a few seconds behind Iridium 75 (25346, 1998-032E).
(06 May 2018): The orbit of Iridium 47 (25106, 1997-082C) has been lowered by 15km and it is presumably being retained as a spare for plane 2.
(04 May 2018): Iridium 148 (43255, 2018-030G) (previously
labelled as Iridium 144) has entered the operational
constellation at Plane 1, Slot 4, a few seconds behind Iridium 70
(25342, 1998-032A).
(03 May 2018): Iridium 150 (43257, 2018-030J) (previously
labelled as Iridium 142) has entered the operational
constellation at Plane 1, Slot 5, a few seconds behind Iridium 62
(25285, 1998-021A).
(03 May 2018): The process of de-orbiting Iridium 21 (25778, 1999-032B) has started.
(01 May 2018): The names of Iridium 144 and Iridium 148 were exchanged, as were the names of Iridium 142 and 150. This was presumably to bring Space-Track's naming in line with that of the Iridium operators.
(29 April 2018): Iridium 13 (24840, 1997-030E) decayed on 29 April 2018
(28 April 2018): Iridium 148 (43249, 2018-030A) (since relabelled as Iridium 144) has entered the operational constellation at Plane 1, Slot 7, a few seconds behind Iridium 64 (25287, 1998-021C).
(27 April 2018): The process of de-orbiting Iridium 72 (25343, 1998-032B) has started.
(26 April 2018): Iridium 149 (43250, 2018-030B)
has entered the operational constellation at Plane 1, Slot 8, a
few seconds behind Iridium 65 (25288, 1998-021D).
(26 April 2018): Iridium 146 (43254, 2018-030F) has entered the
operational constellation at Plane 1, Slot 9, a few seconds
behind Iridium 66 (25289, 1998-021E).
(25 April 2018): The orbit of Iridium 11 (tracked as 25578, 1998-047B) has been lowered by 15km and it is presumably being retained as a spare for plane 2.
(21 April 2018): Iridium 150 (43256, 2018-030H) (since
relabelled as Iridium 142) has entered the operational
constellation at Plane 1, Slot 10, a few seconds behind Iridium
67 (25290, 1998-021F).
(21 April 2018): Iridium 157 (43251, 2018-030C) has entered the
operational constellation at Plane 1, Slot 11, a few seconds
behind Iridium 68 (25291, 1998-021G).
(19 April 2018): The process of de-orbiting Iridium 25 (24904, 1997-043B) has started.
(18 April 2018): Iridium 94 (27374, 2002-005C) decayed on 18 April 2018
(17 April 2018): Iridium 145 (43253, 2018-030E)
has entered the operational constellation at Plane 1, Slot 1, a
few seconds behind Iridium 21 (25778, 1999-032B).
(16 April 2018): Iridium 143 (43258, 2018-030K) has entered the
operational constellation at Plane 1, Slot 2, a few seconds
behind Iridium 72 (25343, 1998-032B).
(13 April 2018): The orbit of Iridium 35 (24966, 1997-056B) has been lowered by 15km and it is presumably being retained as a spare for plane 4.
(7 April 2018): The orbit of Iridium 20 (tracked as 25577, 1998-047A) has been lowered by 15km and it is presumably being retained as a spare for plane 2.
(7 April 2018): Iridium 19 (24965, 1997-056A) decayed on 7 April 2018
(30 March 2018): The fifth Iridium Next launch took place on 30 March 2018 and was directed towards orbital plane 1. It included Iridiums 140, 142, 143, 144, 145, 146, 148, 149, 150 and 157.
(29 March 2018): Iridium 23 (24906, 1997-043D) decayed on 28-29 March 2018.
(23 March 2018): The orbit of Iridium 12 (24837, 1997-030B) has been lowered by 15km and it is presumably being retained as a spare for plane 5.
(22 March 2018) Iridium 128 (42811, 2017-039J) is reported as having entered service at Plane 4, Slot 3, replacing Iridium 35 (24966, 1997-056B). It has probably been in service for several weeks while still migrating.
(19 March 2018): Iridium 113 (42803, 2017-039A)
and Iridium 120 (42805, 2017-039C) have completed migration from
Orbital Plane 3 to Orbital Plane 2, and have been raised to the
operational orbit as follows:
Iridium 120 (42805, 2017-039C) has entered the operational
constellation at Plane 2, Slot 7, a few seconds behind Iridium 47
(25106, 1997-082C).
Iridium 113 (42803, 2017-039A) has entered the operational
constellation at Plane 2, Slot 8, a few seconds behind Iridium 20
(25577, 1998-047A).
Iridiums 120 and 113 are reported as having entered service on 23
March 2018.
(17 March 2018): The process of de-orbiting Iridium 13 (24840, 1997-030E) has started.
(10 March 2018): The orbit of Iridium 76 (25432,
1998-048B) has been lowered by 15km and it is presumably being
retained as a spare for plane 2.
(09 March 2018): The orbit of Iridium 97 (27450, 2002-031A) has
been lowered by 15km and it is presumably being retained as a
spare for plane 4.
(09 March 2018): The process of de-orbiting Iridium 90
(27373, 2002-005B) has started. Iridium 90 was launched
to orbital plane 3, but migrated to orbital plane 5. It was never
used in operational service.
(01 March 2018): The process of de-orbiting Iridium 94 (27374, 2002-005C) has started.
(28 February 2018): Iridium 105 (2017-003E) and
Iridium 108 (2017-003H) have completed migration from Orbital
Plane 6 to Orbital Plane 5, and have been raised to the
operational orbit as follows:
Iridium 105 (41921, 2017-003E) has entered the operational
constellation at Plane 5, Slot 8, a few seconds behind Iridium 12
(24837, 1997-030B).
Iridium 108 (41924, 2017-003H) has entered the operational
constellation at Plane 5, Slot 9, a few seconds behind Iridium 13
(24840, 1997-030E).
Iridiums 105 and 108 are reported as having entered service on 5
March 2018.
(13 February 2018): Iridium 49 (25108,
1997-082E) decayed on 13 February 2018.
(11 February 2018): Iridium 43 (25039, 1997-069A) decayed
on 11 February 2018.
(10 February 2018): The orbit of Iridium 25 (24904, 1997-043B)
has been lowered by 15km and it is presumably being retained as a
spare for plane 2.
(10 February 2018): The process of de-orbiting Iridium 23
(24906, 1997-043D) has started.
(8 February 2018): Iridium 3 (25431, 1998-048A) decayed
on 8 February 2018.
(7 February 2018): The process of de-orbiting Iridium 46
(tracked as 24905, 1997-043C) has started.
(5 February 2018): It has been reported that 32 Iridium Next
satellites are now in service.
(3 February 2018): Iridium 11 (tracked as 25578, 1998-074B) has
been moved from Plane 2, Slot 10 (now covered by Iridium 130) to
Plane 2, Slot 1, close to Iridium 134 (43075, 2017-083F).
(29 January 2018): Iridium 141 (43077, 2017-083H) has entered the
operational constellation at Plane 2, Slot 2, a few seconds
behind Iridium 94 (27374, 2002-005C).
(29 January 2018): Iridium 137 (43076, 2017-083G) has entered the
operational constellation at Plane 2, Slot 3, a few seconds
behind Iridium 76 (25432, 1998-048B).
(26 January 2018): The process of de-orbiting Iridium 49
(25108, 1997-082E) has started.
(26 January 2018): Iridium 116 (43072, 2017-083C) has entered the
operational constellation at Plane 2, Slot 4, a few seconds
behind Iridium 25 (24904, 1997-043B).
(23 January 2018): Iridium 135 (43070, 2017-083A) has entered the
operational constellation at Plane 2, Slot 5, a few seconds
behind Iridium 23 (24906, 1997-043D).
(21 January 2018): The process of de-orbiting Iridium 3
(25431, 1998-048A) has started.
(21 January 2018): Iridium 151 (43074, 2017-083E) has entered the
operational constellation at Plane 2, Slot 6, a few seconds
behind Iridium 46 (tracked as 24905, 1997-043C).
(early January 2018): Iridium 128 (42811, 2017-039J), which is
still migrating from orbital plane 3, into which it was launched,
towards orbital plane 4, has been raised to the operational
altitude, and is presumably intended to cover Plane 4, Slot 3,
currently occupied by Iridium 35 (24966, 1997-056B).
(15 January 2018): Iridium 138 (43071, 2017-083B) has entered the
operational constellation at Plane 2, Slot 9, a few seconds
behind Iridium 49 (25108, 1997-082E).
(12 January 2018): The process of de-orbiting Iridium 37
(24968, 1997-056D) has started.
(12 January 2018): Iridium 130 (43073, 2017-083D) has entered the
operational constellation at Plane 2, Slot 10, a few seconds
behind Iridium 11 (tracked as 25578, 1998-074B).
(12 January 2018): Iridium 131 and Iridium 134 are reported as
having entered service.
(11 January 2018): Iridium 131 (43079, 2017-083K) has entered the
operational constellation at Plane 2, Slot 11, a few seconds
behind Iridium 3 (25431, 1998-048A).
(8 January 2018): Iridium 34 (24969, 1997-056E) decayed
on 8 January 2018.
(8 January 2018): Iridium 134 (43075, 2017-083F) has entered the
operational constellation at Plane 2, Slot 1, a few seconds
behind Iridium 22 (24907, 1997-043E). Iridium 22 may already have
failed on station.
(6 January 2018): Iridium 153 (43078, 2017-083J) appears to have
started migrating towards orbital plane 1.
Iridium 6 (24794, 1997-020C) decayed on 23 December 2017.
The fourth Iridium Next launch took place on 23 December 2017 and was directed towards orbital plane 2. It included Iridiums 116, 130, 131, 134, 135, 137, 138, 141, 151 and 153.
(14 December 2017): The process of de-orbiting Iridium 96 (27376, 2002-005E) has started.
(by early December 2017):
The orbit of Iridium 61 (25263, 1998-018B) has been lowered by
15km and it is presumably being retained as a spare for plane 4.
The orbit of Iridium 37 (24968, 1997-056D) has been lowered by
15km and it is presumably being retained as a spare for plane 4.
The process of de-orbiting Iridium 34 (24969, 1997-056E)
has started.
The process of de-orbiting Iridium 19 (24965, 1997-056A) has
started.
The process of de-orbiting Iridium 6 (24794, 1997-020C) has
started.
(24 November 2017) Iridium 8 (24792, 1997-020A) decayed on 24 November 2017.
(20 November 2017) The orbit of Iridium 6 (24794, 1997-020C) has been lowered by 25km to the Engineering Orbit.
(18 November 2017) Iridium 97 (27450, 2002-031A) has been moved from Plane 4, Slot 4 (now covered by Iridium 107) to Plane 4, Slot 8, a few seconds ahead of Iridium 133 (42955, 2017-061A)
(16 November 2017) The process of de-orbiting Iridium 5 (24795, 1997-020D) has started.
(13 November 2017) Iridium 125 (42964, 2017-061K)
has entered the operational constellation at Plane 4, Slot 9, a
few seconds behind Iridium 96 (27376, 2002-005E).
All of the third batch of 10 Iridium Next satellites have now
been raised to the operational orbit.
(12 November 2017) More satellites have recently
been raised to the operational constellation:
Iridium 139 (42963, 2017- 061J) has entered the operational
constellation at Plane 4, Slot 11, a few seconds behind Iridium
61 (25263, 1998-018B)
Iridium 136 (42962, 2017- 061H) has entered the operational
constellation at Plane 4, Slot 10, a few seconds behind Iridium
37 (24968, 1997-056D)
The process of de-orbiting Iridium 51 (25262, 1998-018A)
has started.
(9 November 2017) More satellites have recently
been raised to the operational constellation:
Iridium 129 (42958, 2017-061D) has entered the operational
constellation at Plane 4, Slot 6, a few seconds behind Iridium 6
(24794, 1997-020C)
Iridium 119 (42959, 2017-061E) has entered the operational
constellation at Plane 4, Slot 1, a few seconds behind Iridium 19
(24965, 1997-056A)
Iridium 132 (42961, 2017-061G) has entered the operational
constellation at Plane 4, Slot 5, a few seconds behind Iridium 5
(24795, 1997-020D)
Iridium 107 (42960, 2017-061F) has entered the operational
constellation at Plane 4, Slot 4, a few seconds behind Iridium 97
(27450, 2002-031A)
(1 November 2017) Iridium 127 (42956, 2017-061B)
has entered the operational constellation at Plane 4, Slot 7, a
few seconds behind Iridium 51 (25262, 1998-018A)
Note: Iridium 7 (24793, 1997-020B), which was paired with Iridium
51, appears to be drifting away from Plane 4, Slot 7.
(1 November 2017): The process of de-orbiting Iridium 8
(24792, 1997-020A) has started.
(28 October 2017) Iridium 133 (42955, 2017-061A)
has entered the operational constellation at Plane 4, Slot 8, a
few seconds behind Iridium 8 (24792, 1997-020A)
(28 October 2017) Iridium 122 (42957, 2017-061C) has entered the
operational constellation at Plane 4, Slot 2, a few seconds
behind Iridium 34 (24969, 1997-056E)
(28 October 2017) The rest of the third batch of 10 Iridium Next
satellites have now been raised to the storage orbit. Iridium 129
(42958, 2017- 061D) is being raised towards the operational
orbit.
(23 October 2017) Most of the third batch of 10 Iridium Next satellites have now been raised to the storage orbit. Iridium 133 (42955, 2017-061A) is now being raised towards the operational orbit.
(9 October 2017) The third batch of 10 Iridium Next satellites (107, 119, 122, 125, 127, 129, 132, 133, 136, 139) were successfully launched to orbital plane 4.
(28 September 2017): Iridium 30 (24949, 1997-051F) decayed on 28 September 2017.
(22 September 2017): Iridium 77 (25471, 1998-051E) decayed on 22 September 2017.
(26 August 2017) The orbit of Iridium 31 (24950, 1997-051G) has been lowered by 15km and it is presumably being retained as a spare for plane 3.
(23 August 2017): The process of de-orbiting Iridium 77 (25471, 1998-051E) has started.
(21 August 2017) The orbit of Iridium 58 (25274,
1998-019C) has been lowered by 15km and it is presumably being
retained as a spare for plane 3.
(12 August 2017) The orbit of Iridium 55 (25272, 1998-019A) has
been lowered by 15km and it is presumably being retained as a
spare for plane 3.
(3 August 2017): The process of de-orbiting Iridium 30 (24949, 1997-051F) has started.
(1 August 2017): It was announced that all 5
Iridium Next satellites remaining in orbital plane 3 were now in
service.
(late July 2017): Iridium 117 (42808, 2017-039F) has been raised
to the operational orbit at Plane 3, Slot 1, a few seconds behind
Iridium 55 (25272, 1998-019A)
(late July 2017): Iridium 115 (42806, 2017-039D) and Iridium 124
(42810, 2017-039H) appear to have started migrating towards
orbital plane 2.
Iridium 113 (42803, 2017-039A) and Iridium 120
(42805, 2017-039C) appear to have started migrating towards
orbital plane 2.
Iridium 117 (42808, 2017-039F) was in process of having its orbit
raised within plane 3.
Iridium 118 (42807, 2017-039E) has been raised to the operational
orbit at Plane 3, Slot 9, a few seconds behind Iridium 58 (25274,
1998-019C)
Iridium 126 (42809, 2017-039G) has been raised to the operational
orbit at Plane 3, Slot 5, a few seconds behind Iridium 30 (24949,
1997-051F)
(15 July 2017) Iridium 123 (42804, 2017-039B) has been raised to
the operational orbit at Plane 3, Slot 4, a few seconds behind
Iridium 31 (24950, 1997-051G).
(13 July 2017) Iridium 121 (42812, 2017-039K) has been raised to
the operational orbit to fill the gap at Plane 3, Slot 8, which
had been vacant since the failure of Iridium 57 (25273,
1998-019B) in May 2016.
Iridium 128 (42811, 2017-039J) had its orbit raised, and appears
to have started migrating towards orbital plane 4.
Other satellites are in process of having their orbits raised.
(25 June 2017) The second batch of 10 Iridium Next satellites were successfully launched to orbital plane 3. Apparently 5 satellites are to remain in orbital plane 3, while the remaining 5 will be drifted to other planes.
(mid-June 2017) Iridium 51 (25262, 1998-018A), which had been paired wth Iridium 6 (24794. 1997-020C) since October 2014, was moved within orbital plane 4 to be paired once again with Iridium 7 (24793, 1997-020B). This is possibly a consequence of a further significant failure of either Iridium 6 or Iridium 7.
(11 June 2017) The orbit of Iridium 74
(25345, 1998-032D) was lowered rapidly starting at the beginning
of June 2017, and it decayed on 11 June 2017.
Iridium 74 had been "spare" in orbital plane 1
for many years, evidently fully controllable, but operationally
unusable.
(17 May 2017) The orbit of Iridium 18 (24872, 1997-034D has been lowered by 15km and it is presumably being retained as a spare for plane 6.
(12 May 2017) The orbit of Iridium 77 (25471,
1998-051E) has been lowered by 15km and it was presumably being
retained as a spare for plane 6.
(11 May 2017) Iridium 43 (25039, 1997-069A) is being
de-orbited.
(04 May 2017) It is now clear that Iridium 98
(27451, 2002-031B), previously at Plane 6, Slot 2, which was
moved around the plane to Plane 6, Slot 9. has now taken over
from Iridum 82 (25467, 1998-051A).
(04 May 2017) Iridium 82 (25467, 1998-051A) is being
de-orbited.
It is now clear that Iridium 80 (25469, 1998-051C),
previously at Plane 6, Slot 5 which was moved around the plane to
Plane 6. Slot 8, has now taken over from Iridum 81 (25468,
1998-051B) .
- The orbit of Iridium 81 has been lowered by 15km and
it is presumably being retained as a spare for plane 6.
** The first eight Iridium Next
satellites are now in service **
Note that the Iridium Next satellites are
not expected to produce flares from the Main Mission Antenna in
the same way as the original Iridium satellites.
Iridium 111 (2017-003K) is in service at
Plane 6. Slot 11, replacing Iridium 43 (25039, 1997-069A).
- Iridium 43 initially remained near its previous orbital
position
Iridium 102 (2017-003D) is in service at Plane
6. Slot 1, replacing Iridium 18 (24872, 1997-034D).
- Iridium 18 initially remained near its previous orbital
position.
Iridium 112 (2017-003J) is in service at Plane
6. Slot 2, replacing Iridium 98 (27451, 2002-031B).
- The orbit of Iridium 98 was lowered by 5km allowing it to move
to another slot in plane 6.
Iridium 104 (2017-003F) is in service at Plane
6. Slot 3, replacing Iridium 40 (25041, 1997-069C).
(07 April 2017) Iridium 40 (25041,
1997-069C) is being de-orbited.
Iridium 114 (2017-003G) is in service
at Plane 6. Slot 4, replacing Iridium 15 (24869, 1997-034A).
- The orbit of Iridium 15 has been lowered by 15km and
it is presumably being retained as a spare for plane 6.
Iridium 103 (2017-003B) is in service at Plane
6. Slot 5, replacing Iridium 80 (25469, 1998-051C).
- The orbit of Iridium 80 has been raised by 10km
allowing it to move to another slot in plane 6.
Iridium 109 (2017-003C) is in service at Plane
6. Slot 6, replacing Iridium 77 (25471, 1998-051E).
- Iridium 77 initially remained near its previous orbital
position
Iridium 106 (2017-003A) is in service at Plane
6, Slot 7.
(First generation Iridium satellites remain active in Slot 8,
Slot 9 and Slot 10 of Plane 6)
Iridium 105 (2017-003E) and Iridium 108 (2017-003H) remain in the insertion orbit, but have now started migrating from Orbital Plane 6 towards Orbital Plane 5
Iridium 111 (2017-003K) was raised to the operational orbit at
Plane 6, Slot 11, a few seconds behind Iridium 43 (25039,
1997-069A)
Iridium 102 (2017-003D) was raised to the operational orbit at
Plane 6, Slot 1, a few seconds behind Iridium 18 (24872,
1997-034D)
Iridium 112 (2017-003J) was raised to the operational orbit at
Plane 6, Slot 2, a few seconds behind Iridium 98 (27451,
2002-031B)
Iridium 104 (2017-003F) was raised to the operational orbit at
Plane 6, Slot 3, a few seconds behind Iridium 40 (25041,
1997-069C)
Iridium 114 (2017-003G) was raised to the operational orbit at
Plane 6, Slot 4, a few seconds behind Iridium 15 (24869,
1997-034A)
Iridium 103 (2017-003B) was raised to the operational orbit at
Plane 6, Slot 5, a few seconds behind Iridium 80 (25469,
1998-051C)
Iridium 109 (2017-003C) was raised to the operational orbit at
Plane 6, Slot 6, a few seconds behind Iridium 77 (25471,
1998-051E)
On 17 February 2017, Iridium Communications announced that the launch of the second batch of 10 Iridium Next satellites was now delayed until mid-June, 2017
It was also announced on 17 February 2017 that the first of the Iridium Next satellites (i.e. Iridium 106) was expected to begin providing service to customers in the next few days.
By 14 February 2017, Iridium 106 (2017-003A) had been raised
to the operational orbit to fill the gap at Plane 6, Slot 7,
which had been vacant since the failure of Iridium 39 (25042,
1997-069D) in June 2016
Iridium 103 (2017-003B), Iridium 109 (2017-003C), Iridium 102
(2017-003D), Iridium 104 (2017-003F), Iridium 114 (2017-003G),
Iridium 112 (2017-003J), and Iridium 111 (2017-003K) were all in
the 700km * 705km storage orbit.
Iridium 105 (2017-003E) and Iridium 108 (2017-003H) still
remained in the 605km * 625km insertion orbit.
The first Iridium Next launch (2017-003) took place on 14
January 2017, lifting the first ten Iridium Next satellites to
Orbital Plane 6.
Initially all 10 Iridium Next satellites were in a 605km * 625km
insertion orbit.
On 22 January 2017, Iridium 106 (2017-003A) was the first to have
its orbit raised by about 10km, presumably following a successful
initial check-out.
On 24 January 2017, Iridium 103 (2017-003B) had its orbit raised
by about 10km.
On 25 January 2017, Iridium 106 (2017-003A) was raised
significantly to a 700km * 705km storage orbit.
By 28 January 2017, Iridium 103 (2017-003B) and Iridium 109
(2017-003C) had also been raised to the 700km * 705km storage
orbit., and Iridium 102 (2017-003D) was in the process of being
raised.
Over the next few days, Iridium 102 (2017-003D), Iridium 104
(2017-003F), and Iridium 114 (2017-003G) were also raised to the
700km * 705km storage orbit.
It initially seemed unlikely that any of the Iridium Next satellites launched to Oribital Plane 6 would be moved to other orbital planes, as any gaps in those planes caould be filled more quickly by the launches direct to those planes that are expected to take place in the coming months.
The status of the Iridium constellation immediately prior to the first Iridium Next launch appears to have been as follows:
(At this time, it was reported that 64 of the original Iridium satellites still remained operational)
Orbital <-------------- Operational satellites --------------> Spares Plane Plane 1: 21 72 75 70 62 14 64 65 66 67 68 74 (note: Iridium 74 is probably a partial failure) Plane 2: 22 94 76 25 23 46 47 20 49 11 3 (note: Iridium 23 is probably a partial failure) Plane 3: 55 95 45 31 30 32 91 58 59 60 Plane 4: 19 34 35 97 5 6/51 7 8 96 37 61 (note: Iridiums 6, 7 and 51 are probably partial failures) Plane 5: 50 56 52 53 84 10 54 12 13 83 86 90 (launched to plane 3, but has been migrated to plane 5) Plane 6: 18 98 40 15 80 77 81 82 41 43
Original <----- Failed -----> <- Failed -> Note that some of the failed satellites have drifted from the original orbital planes Orbital (but still in orbit) (decayed) Plane Plane 1: 73t 63 Plane 2: 69t 24t 71t 26 48d Plane 3: 28 29 33t 57 27d Iridium 33 was fragmented by the collison with Cosmos 2251 on February 10, 2009 Plane 4: 4 36t Plane 5: 2t 914t 911t 16t 85d 9d Iridium 2 has drifted far from its original launch plane, and continues to drift Plane 6: 920t 921t 44t 38t 17t 42t 39 79d
t indicates satellites that have been reported as tumbling out of control.
In their quarterly report dated 30 June, 2016, Iridium Satellite LLC acknowledged the failure of two satellites in the preceding quarter year.
In June 2016, Iridium 15 (24869, 1997-034A) was moved from Plane 6, Slot 7 to Plane 6, Slot 4, replacing Iridium 39 (25042, 1997-069D). The intention may have been to swap over the two satellites but, in any case problems were experienced with with Iridium 39, which was then removed from the operational constellation, leaving a gap at Plane 6, Slot 7. No spare was available to replace it.
In May 2016, Iridium 57 (25273, 1998-019B) began to drift away slowly from its nominal position (Plane 3, Slot 8) and has presumably failed. See Iridium 57 looks to have a bad attitude.
In the middle of 2015, Iridium 45 (25104, 1997-082A) which had been migrating from orbital plane 2 towards orbital plane 3 for about 14 months, arrived in oribital plane 3. It appears to have already been in operational use as part of orbital plane 3 for some months previously, even though it was not in its final orbital location (Plane 3, Slot 3).
In early December 2014, Space-Track catalogued four items of debris (40324-40327, 2002-05G to 2002-05K) associated wth the 2002-05 launch .These are labelled by Space-Track as "IRIDIUM 91 DEB", and seem to be associated with Iridium 91 (27372, 2002-005A) which appears, however, to remain fully operational.
In early October 2014, Iridium 51 (25262, 1998-018A), which had been paired wth Iridium 7 (24793, 1997-020B) was moved within orbital plane 4 to be paired with Iridium 6 (24794. 1997-020C).
At the end of August 2014, Iridium 14 (25777, 1999-032A) , whch had been spare in orbital plane 1 since launch, was raised to operational altitude to replace Iridium 63 (25286. 1998-021B), which had presumably failed.
At the end of August 2014, Iridium 98 (27451, 2002-301B) , whch had been spare in orbital plane 6 since migrating from plane 4, was raised to operational altitude a few seconds behind Iridium 42 (25077. 1977-077) which had presumably failed. Iridium 42 has since been reported to be flashing.
By early 2014, Iridium 45 (25104, 1997-082A) was no longer maintaining its place in orbital plane 2, and was evidently migrating towards orbital plane 3. Its place in orbital plane 2, slot 5 was taken by Iridium 23 (24906, 1997-043D).
By early 2014, Iridium 29 (24944, 1997-051A) had ceased to maintain its position in the constellation, and had presumably failed. At that time, there was no spare available in plane 3 to replace it..
On 20 November, 2012, Iridium 96 (27376, 2002-005E), previously spare in orbital place 3, began migrating towards orbital plane 4, which had no on-orbit spare, This left orbital place 3 without a spare. The migration took around twelve months. Iridium 96 took over from failed Iridium 4 (24796, 1997-020E). Iridium 96 was raised to operational altitude several months before its arrival in plane 4 and appears to have been brought into use at that time.
On 13 November, 2012, Iridium 94 (27374, 2002-005C), which had been migrating over the past year from orbital place 3, arrived at orbital plane 2, and was immediately raised to operational altitude to replace Iridium 23 (24906, 1997-043D) which had evidently failed, though retaining at least some functionality. Iridium 23 initially remained at operational altitude a few seconds behind Iridium 94, but was later used to replace Iridium 45 (25104, 1997-02A).
In mid 2012, Iridium 4 (24796, 1997-020E) ceased to maintain its position in the constellation. At that time, Plane 4 had no on-orbit spare
In late July 2012, Iridium 51 (25262, 1998-018A). which had been out of the operational constellation for many years, was moved in the position previously occupied by Iridium 7 (24793, 1997-020B), while Iridum 7 was moved to follow slightly behind it. The two satellites were each providing some of the functionality for the given slot. Orbital Plane 4 has no other spare satellite.
In early August 2011, Iridium 11 (originally 25577, 1998-074A,
but currently labelled by Space-Track as 25578, 1998-074B), which had apparently taken over from
Iridium 23 (24906, 1997-043D) in November 2010, was moved
around the plane, evidently to take
over from Iridium 26 (24903, 1997-043A).
This suggests that Iridium 26 must have failed on station, and
also that Iridium 23 retained some functionality.
Orbital Plane 2 had no other spare satellite, but Iridium 94 (27374, 2002-005C) was in process
of migrating from Orbital Place 3.
In early November 2010, Iridium 11 (originally 25577, 1998-074A, but currently labelled by Space-Track as 25578, 1998-074B), previously spare, was raised to the operational orbit, just a few seconds behind Iridium 23 (24906, 1997-043D). This suggests that Iridium 23 must have failed on station, but possibly only partially.
In early March 2009, Iridium 91 (27372, 2002-005A) [note that some sources still label this satellite as Iridium 90] was raised to the operational orbit to fill the gap left by the loss of Iridium 33.
On February 10, 2009 at 16:56 UT, Iridium 33 (24946, 1997-051C) was in collision with Cosmos 2251 (22675, 1993-036A) . See Iridium 33 collision. Iridium 33 is no longer functional.
In late July 2008, Iridium 95 (27375, 2002-005D), up till then a spare satellite in orbital plane 3, entered the operational constellation, evidently to replace Iridium 28 (24948, 1997-051E). Initially, Iridium 28 remained close to its nominal position in the constellation, so had presumably failed on station.
(January 2008) Iridium 90 [previously labelled as Iridium 91] which had been manouvering since mid October 2005, has arrived in orbital plane 5
(May 2007) Iridium 98, which had been manouvering since late June 2005, has arrived in orbital plane 6
In early January 2007, Iridium 97 (27450,2002-031A), a spare satellite in orbital plane 4, entered the operational constellation, evidently to replace Iridium 36 (24967, 1997-056C). Iridium 36 initially remained close to its nominal position in the constellation - it had evidently failed on station.
On or about January 10, 2006, Iridium 21 (25778, 199-032B), one of two spare satellites in orbital plane 1, was raised to operational altitude, presumably to replace Iridium 74 (25345, 1998-032B),. which was lowered to the engineering orbit. It is unclear whether Iridium 74 has failed completely
On January 1, 2006, the Spacecom labelling of Iridium 90 and Iridium 91 was interchanged. There was no change to the operational constellation.
In August 2005, Iridium 17 evidently failed, and Iridium 77 took its place in the operational constellation. This left orbital plane 6 without a spare satellite.
In April 2005, Iridium 16 was removed from the operational constellation, and subsequently Iridium 86 took its place in the operational constellation. This left orbital plane 5 without a spare satellite.
On January 29, 2004, the OIG/Spacecom labelling of Iridium 11 and Iridium 20 was
interchanged.
There was no change to the operational constellation.
Iridium 82 replaced Iridium 38 in orbital plane 6 on or about September 17, 2003.
Iridium 30 and 31 exchanged places in the constellation on September 19-22, 2002.
2 further spares (Iridium 97 and 98) were launched at 0933 UT on 20 June 2002 from Plesetsk Cosmodrome by Eurockot.. This launch was directed at orbital plane 4. Iridium 98 was subesquently moved to orbital plane 6.
5 additional spare Iridium satellites (Iridium 90, 91, 94, 95 and 96) were launched from Vandenberg AFB aboard a Delta II rocket on 11 February 2002 at 17:43:44 UT. The originally intended launch on 8 February 2002 at 18:00:30 UT was scrubbed at the last moment, while the launch opportunities on 9 February 2002 at 17:54:55 UT and 10 February 2002 at 17:49:19 UT also had to be scrubbed. See http://www.boeing.com/news/releases/2002/q1/nr_020211s.html and http://spaceflightnow.com/delta/d290/status.html for more details on the launch. This launch was directed at orbital plane 3, which previously had no spares. Perhaps surprisingly, there was initially no indication that it was intended to drift some of the spares to other orbital planes. However, Iridium 90 (initially labelled as Iridium 91) was subesquently moved to orbital plane 5, and Iridium 94 was later moved to orbital plane 2. Iridium 96 is now being moved towards plane 4.
@ Iridium 5 and Iridium 51 were confused during August 2001.
The previous change to the operational constellation was the replacement of Iridium 9 by Iridium 84.
Additional Notes:
Iridium 2 has drifted far from its original orbital plane (as have several of the tumbling satellites). At one time, it was deliberately allowed to drift to become the spare in another plane (plane 4?), but it evidently failed on arrival in the new plane, and continues to drift out of control.
At the Iridium Satellite LLC press conference call on 12
December 2000
(see http://www.ee.surrey.ac.uk/Personal/L.Wood/constellations/iridium/conference-call-Dec-2000.html),
a figure of 8 operational spares was quoted. This would include
Iridium 82, 84 and 86 which have since become operational.
Also at the Iridium Satellite LLC press conference call on 12
December 2000
(see http://www.ee.surrey.ac.uk/Personal/L.Wood/constellations/iridium/conference-call-Dec-2000.html),
plans were announced to launch further spare satellites for the
constellation:
"We'll be launching seven more in the next year or so.
We have the first launch scheduled for next June, June of 2001.
That will be a Delta 2 launch; we'll be putting five spare
satellites into orbit. The following spring, roughly March of
2002, we'll be launching two more and in that case we'll be using
the Russian rocket. So we will inject seven more spares into the
system, so we'll have more than two spares in each orbit, and
that will give us the life that we believe is there"
These launches were in fact delayed until 2002.