News

As endorsed by the Joint Steering Group held on September 14th, Jason-1 satellite will be performing a series of maneuvers between 28-Sept and 17-Oct 2011, to burn off excess hydrazine.

As endorsed by the Joint Steering Group held on September 14th, Jason-1 satellite will be performing a series of maneuvers between 28-Sept and 17-Oct 2011, to burn off excess hydrazine. This plan is a pre-requisite to get authorization for continuing the mission over the next 2 years. It is now relevant thanks to the succesful thrusters test maneuvers performed early September 2011.

The nominal plan will consist of 13 (TBC) pairs of long-thrust inclination maneuvers. Each maneuver will consist of a pair of 600-second thrusts that will alternately change the inclination by either +0.03-degrees or -0.03-degrees. There will only be one maneuver (1 pair of burns) each working day (hence none on weekends). A preliminary schedule is given below and will be updated daily in front of the real efficiency of the burns. Thus, additional maneuvers may be decided at any time.

These maneuvers will be qualitatively similar to the Jason-1 maneuvers that occurred earlier in September where the thrust sequences and thruster performance were tested.

During the period, latency and quality of IGDR products will be degraded. All the teams at CNES & JPL will do their best in order to minimize the impacts but we ask you to process carefully the data. Indeed orbit for near real time (OSDR) and off-line (I/GDR) products will be less accurate than usual and may be affected even by potential data gaps. No noticeable impact is expected on Ssalto/Duacs products. Of course IGDR products will be processed without time constraints leading to some delivery delays. The following Jason-1 Science cycles will be degraded: end of cycle 358, cycle 359, cycle 360.

#       Date & time   
1       28/09/2011 22h47m49s640 329.53 { Orbital - Descending node pass time }
1       29/09/2011 01h36m29s038 107.01 { Orbital - Ascending node pass time } 
2       29/09/2011 23h09m24s550 321.03 { Orbital - Descending node pass time }
2       30/09/2011 01h58m03s952 98.51 { Orbital - Ascending node pass time }  
3       02/10/2011 22h21m43s497 323.86 { Orbital - Descending node pass time }
3       03/10/2011 01h10m22s929 101.34 { Orbital - Ascending node pass time } 
4       03/10/2011 23h39m14s504 121.26 { Orbital - Ascending node pass time } 
4       04/10/2011 02h27m52s276 258.74 { Orbital - Descending node pass time }
5       04/10/2011 21h12m09s787 335.28 { Orbital - Descending node pass time }
5       05/10/2011 00h00m49s210 112.75 { Orbital - Ascending node pass time } 
6       05/10/2011 21h33m44s510 326.77 { Orbital - Descending node pass time }
6       06/10/2011 00h22m23s952 104.25 { Orbital - Ascending node pass time } 
7       06/10/2011 21h55m19s223 318.27 { Orbital - Descending node pass time }
7       07/10/2011 00h43m58s661 95.75 { Orbital - Ascending node pass time }  
8       09/10/2011 21h07m37s599 321.11 { Orbital - Descending node pass time }
8       09/10/2011 23h56m17s056 98.58 { Orbital - Ascending node pass time }  
9       10/10/2011 22h25m26s000 118.43 { Orbital - Ascending node pass time } 
9       11/10/2011 01h14m03s734 255.91 { Orbital - Descending node pass time }
10      11/10/2011 22h47m00s685 109.92 { Orbital - Ascending node pass time } 
10      12/10/2011 01h35m38s435 247.41 { Orbital - Descending node pass time }
11      12/10/2011 23h08m35s386 101.42 { Orbital - Ascending node pass time } 
11      13/10/2011 01h57m13s157 238.9 { Orbital - Descending node pass time } 
12      13/10/2011 21h37m44s324 121.26 { Orbital - Ascending node pass time } 
12      14/10/2011 00h26m22s040 258.75 { Orbital - Descending node pass time }
13      16/10/2011 20h50m02s667 124.1 { Orbital - Ascending node pass time }  
13      16/10/2011 23h38m40s373 261.58 { Orbital - Descending node pass time }