Headline : Explained: What makes PSLV-C45 special
- ISRO has successfully launched the PSLV-C45 ferrying satellites to multiple orbits in a single launch.
- PSLV-C45 mission involved launching of following satellites in 3 different orbits
- EMISAT – 749 km
- 28 foreign satellites – 504 km
- Experimental satellites – 485 km
Unique features of PSLV-C45
The PSLV-C45 launch is unique in following ways
- PSLV-QL variant
- It was used for the 1st time
- PSLV-QL has 4 strap-on motors to provide additional thrust at various stages of the rocket travel.
- 3- Orbits in single launch
- This is the 1st time ISRO launched satellites in 3 different orbits
- PS-4 as orbital platform
- In a normal scenario, the last stage of a PSLV rocket PS-4, after releasing the primary satellite in space becomes dead and categorized as space debris.
- In PSLV-C45, the PS-4 stage moved to a lower orbit at around 458 km to establish an orbital platform.
- This orbital platform is then used to house experimental satellites
- Multiple-firing of 4th stage
- In order to inject satellites into multiple orbits, for the 1st time the 4th stage engine was fired twice.
- Normally engines used to fire only once.
In brief: Multiple orbit launch
- In the 1st step PSLV C-45 placed EMISAT to the 748 km sun-synchronous polar orbit.
- Then it made one complete revolution around Earth pole to pole.
- It lowered itself into an 504 km orbit, injected the 28 international customer satellites,
- Made another round of Earth, pole to pole and attained a lower orbit of 485 km, where the fourth stage of the rocket will act as orbital platform for experimental satellites.
- The 4th stage engines fired twice in order to achieve the additional revolution around the earth.
- The PS-4 stage experimental satellites include
- ARIS satellite of Indian Institute of Space Science and Technology to study the structure and composition of ionosphere.
- Automatic Identification System (AIS) for Maritime satellite applications
- Amateur radio applications satellite