Orbit

From its launch on February 2013 to July 2016, Saral/AltiKa has a repetitive orbit, on the same ground-track as Envisat (during its repetitive orbit, before 2010/10) with a 501-pass, 35-day exact repeat cycle on a sun-synchronous orbit (see below these paramters). It is complentary to Jason-2 ground tracks. Due to technical issues on the reaction wheels from March 2015, CNES and ISRO have decided to pursue this mission with a new phase named “SARAL-DP” for SARAL-Drifting Orbit". From July 2016, and during this drifting phase, the repetitive ground track are no more maintained and with the natural decay of the orbit, the ground track will drift.

The mean classical orbit elements duriong the repetitive phase (2013-2016) are given in the table below:

Pass locator

Referenced orbit Saral

Orbit parameters (repetitive phase 2013/02 - 2016/07)

Main characteristics
Semi-major axis7159.496 km
Eccentricity0.000165
Argument of perigee90.0°
Inclination (sun-synchronous)98.55°
Auxiliary data
Mean altitude800 km
Nodal period100.59 min
Repeat cycle35 days
Number of revolution per cycle501
Ground track separation at Equator75 km
Orbital velocity7.47 km/s