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List

A table containing all major information can be found here.

The DORIS satellites list
Name Cospar Launch Mission End Video
SENTINEL-3C26209012026-09-15-
HY-2E26149012026-07-01-
SENTINEL-6B25264012025-11-17-
SWOT22173012022-12-16-
HY-2D21043012021-05-19-
SENTINEL-6A20086012020-11-21-
HY-2C20066012020-09-21-
SENTINEL-3B18039012018-04-25-
SENTINEL-3A16011012016-02-16-
JASON-316002012016-01-17-
SARAL13009012013-02-25-
HY-2A11043012011-08-152020-09-14
CRYOSAT-210013012010-04-08-
JASON-28032012008-06-202019-10-10
STPSat-17006042007-03-092009-10-07
SPOT-52021012002-05-042015-12-11
ENVISAT2009012002-04-012012-05-09
JASON-11055012001-12-072013-06-21
SPOT-498017011998-03-242013-06-24
SPOT-393061011993-09-261996-11-14
TOPEX/POSEIDON92052011992-08-102005-10-09
SPOT-290005011990-01-222009-07-29

 

 


Timeline of the DORIS constellation

Constellation2026

 

 

The constellation

2026 DORISconstellation

The DORIS constellation as of June 2026.

 

 

Orbit plans

2026 OrbitPlans

 

 

Tandem phases

The term tandem is used for the intercalibration phase between a new mission and the previous one, one following the other in the same orbit at less than one minute. The tandem phases have been implemented after the launch of each new altimetry reference mission: Topex-Poseidon and Jason-1 (2002), Jason-1 and Jason-2 (2008), Jason-2 and Jason-3 (2016), and Jason-3 and Sentinel-6A (2021–2022).Note that the term tandem phase may also have been used when Topex was on the inter-track of Jason-1, during the last phase of the Topex mission (from September 2022).

  • Topex-Poseidon / Jason-1: 2002/01/15 (Jason-1’s first cycle) - 2002/08/15 (Jason-1 behind Topex (AC), 70s apart)
  • Jason-1 / Jason-2: 2008/07/04 - 2009/01/26 (Jason-2 behind Jason-1, 55s apart)
  • Jason-2 / Jason-3: 2016/02/12 - 2016/10/02 (Jason-3 behind Jason-2, 80s apart)
  • Jason-3 / Sentinel-6A: 2020/12/18 – 2022/04/07 (Jason-3 ahead Sentinel-6A, 30 seconds apart)
  • Jason-3 / Sentinel-6A: (2nd tandem phase) 2025/01/30 - 2025/06/02 (Sentinel-6A ahead Jason-3, 1 minute apart)
  • Sentinel-3A / Sentinel-3B: 2018/06/07 – 2018/10/16 (Sentinel-3B ahead Sentinel-3A, 30 seconds apart)
  • Sentinel-6A / Sentinel-6B: scheduled 2025/12/18 - 2026/11/17 (Sentinel-6B behind Sentinel-6A, 30 seconds apart)

Note: all dates are YYYY/MM/DD

 

 

Orbit changes

Topex-Poseidon

  • Launch: 1992/08/10
  • Maneuver sequence: 1992/08/17 – 1992/09/21
  • Reference orbit: 1992/09/21 – 2002/08/15
  • Maneuver sequence: 2022/08/15-2002/09/16
  • Interleaved orbit: 2002/09/16 – 2006/01/18
  • End of science mission: 2005/10/09
  • Satellite turned off: 2006/01/18

Jason-1 (Poseidon-2)

  • Launch: 2001/12/07
  • Maneuver sequence: 2001/12/11 – 2001/12/20
  • Reference orbit: 2001/12/20 – 2009/01/26
  • Maneuver sequence: 2009/01/26 – 2009/02/14
  • Interleaved orbit: 2009/02/15 – 2012/04/24
  • Maneuver sequence: 2012/04/25 -2012/05/02
  • Drifting geodetic orbit (406-day period; 1324km): 2012/05/03 – 2013/07/01
  • End of science mission: 2013/06/21
  • Satellite passivated and decommissioned: 2013/07/01

Jason-2 (Poseidon-3)

  • Launch: 2008/06/20
  • Maneuver sequence: 2008/06/23 – 2008/07/04
  • Reference orbit: 2008/07/04 – 2016/10/02
  • Maneuver sequence: 2016/10/02 – 2016/10/13
  • Interleaved orbit: 2016/10/13 - 2017/05/17
  • Maneuver sequence: 2017/07/03 – 2017/07/10
  • Long Repeat Orbit (LRO; 1309.5km): 2017/07/11 – 2018/07/16
  • Maneuver sequence: 2018/07/16 – 201/07/18
  • Interleaved Long Repeat Orbit (i-LRO; shifted 4 km from LRO*; 1309km): 2018/07/19 – 2019/10/01
  • End of mission: 2019/10/01
  • Satellite passivated and decommissioned: 2019/10/10

Jason-3 (Poseidon-3B)

  • Launch: 2016/01/17
  • Maneuver sequence: 2016/01/19– 2016/02/11
  • Reference orbit: 2016/02/12 – 2022/04/07
  • Maneuver sequence: 2022/04/07 – 2022/04/24
  • Interleaved orbit: 2022/04/25 – 2025/01/07
  • Maneuver sequence: 2025/01/07 – 2025/01/28
  • Reference orbit: 2025/01/29 – 2025/06/02
  • Maneuver sequence: 2025/06/02 – 2025/06/17
  • Long Repeat Orbit (LRO): 2025/06/18 - 2026/06/23
  • Maneuver sequence: 2026/06/23 – 2026/06/25
  • Interleaved Long Repeat Orbit (i-LRO; shifted 4 km from LRO): 2026/06/26 - today

Swot (Poseidon-3C)

  • Launch: 2022/12/16
  • 1-day CalVal orbit (altitude 857 km): 2022/12/16 – 2023/07/10
  • Maneuver sequence: 2023/07/11 – 2023/07/21
  • 21-day Science orbit (altitude 890 km): 2023/07/21 – today

SPOT-4

  • Launch: 1998/03/24
  • Nominal orbit: 1998/03/24 - 2009/12/08
  • Maneuver sequence: 2009/12/08 and 2010/02/02 (altitude slightly increased then lowered to correct orbital drift from 70º (drifted situation) to 166º (nominal position) between SPOT-4 and SPOT-5)
  • Nominal orbit: 2010/01/ - 2013/01/29 (end of trade mission on 2013/01/11)
  • Maneuver sequence: 2013/01/29
  • TAKE5 orbit (3 km lower orbit, 5-day repeat cycle): 2013/01/29 (start of TAKE5 mission on 2013/01/31) – 2013/06/19
  • End of mission: 2013/06/29

SPOT-5

  • Launch: 2002/05/04
  • Nominal orbit: 2002/05/04 - 2015/04/02 (end of trade mission on 2015/03/31)
  • Maneuver sequence: 2015/04/02
  • TAKE5 orbit (2.5 km lower orbit, 5-day repeat cycle): 2015/04/02 (start of TAKE5 mission on 2015/04/08) – 2015/12/01
  • Desorbitation maneuver sequence: 2015/12/01 (start)
  • End of mission: 2015/12/11

Envisat

  • Launch: 2002/03/01
  • Initial orbit: 2002/03/04 - 2010/10/21
  • Maneuver sequence: 2010/10/22 - 2010/10/26
  • Extension orbit (17 km lower orbit): 2010/10/27 – 2012/05/09
  • End of mission: 2012/05/09

HY-2A

  • Launch: 2011/08/15
  • 14-day initial orbit (altitude 971 km): 2011/08/15 – 2016/03/23
  • Maneuver sequence: 2016/03/23
  • 168-day geodetic orbit (altitude 973 km): 2016/03/24 – 2020/09/14
  • End of mission: 2020/09/14

Saral

  • Launch: 2013/02/25
  • Initial orbit: 2013/02/25 - 2016/07/03
  • Maneuver sequence: 2016/07/04
  • Drifting phase (Saral-DP) (semi-major increased +1 km): 2016/07/04 – today

Sentinel-3B

  • Launch: 2018/04/25
  • Initial Orbit (Sentinel-3B 30 seconds in front of Sentinel-3A): 2018/06/06 – 2018/10/16
  • Maneuver sequence: 2018/10/16 – 2018/11/27
  • Routine Orbit (Sentinel-3B 140 degrees in front of Sentinel-3A): 2018/11/27 – today

Note: all dates are YYYY/MM/DD

*About Jason's LRO:

LRO #1 Jason-2 July 2017 to July 2018
LRO #2 Jason-2 July 2018 to September 2019 (shifted 4 km from LRO #1)
LRO #3 Jason-3 June 2025 to June 2026 (shifted 2 km from LRO #1)
LRO #4 Jason-3 July 2026 to July 2027 (shifting 4 km from LRO #3, or 2 km from LRO #1) 

 

Video



The DORIS constellation as of February 2022. See also DORIS constellation 2016.