Context:
Green Propulsion System under the Technology Development Fund (TDF) scheme, Defence Research Development Organisation (DRDO) has successfully demonstrated in-orbit functionality on a payload launched by PSLV C-58 mission.
Green Propulsion System:
- Development Agency – Bengaluru-based start-up Bellatrix Aerospace Pvt Ltd
- Uses a 1N Class Green Monopropellant for altitude control and orbit keeping of microsatellites.
- Propulsion system –
- Indigenously-developed
- Non-toxic and environment-friendly for low orbit space,
- The system is ideal for space missions with high thrust requirements
PSLV-C58 Mission:
- Developed by ISRO
- Aim – To investigate the polarization of intense X-ray sources.
- Lauched X-ray Polarimeter Satellite (XPoSat) into an Eastward low inclination orbit
- 1st dedicated scientific satellite from ISRO to carry out research in space-based polarisation measurements of X-ray emission from celestial sources
- Uses – Measuring X-ray polarization, aids astronomers in studying magnetic field orientations and strengths in celestial bodies, crucial for understanding pulsars, black hole regions, and other X-ray-emitting cosmic phenomena.
Polar satellite launch vehicle (PSLV) vs. Geosynchronous satellite launch vehicle (GSLV):
| Polar satellite launch vehicle (PSLV) | Geosynchronous satellite launch vehicle (GSLV) | |
| Altitude | 600-900 km | Upto 36000 km |
| Lift of Mass | 320 tonnes | 415 tonnes |
| Payload | 1,750 kg | 5000 kg |
| Number of stages | 4 | 3 |
| 1st & 3rd stage – Solid rocket motors 2nd & 4th stages – Liquid rocket engines | 1st stage –Solid rocket motor 2nd stage – Liquid fuel 3rd stage – Cryogenic engine | |
| Delivery of | Earth-observation or remote-sensing’ satellites | Communication satellites |
| Delivery to | Sun-Synchronous Polar Orbits | Highly elliptical Geosynchronous Transfer Orbit (GTO) |
| View of satellite from earth | Orbit the earth from pole-to-pole | Appear to remain permanently fixed in same position in the sky |
Source: The Hindu
Previous Year Question
With reference to India’s satellite launch vehicles, consider the following statements:
1. PSLVs launch the satellites useful for Earth resources monitoring whereas GSLVs are designed mainly to launch communication satellites.
2. Satellites launched by PSLV appear to remain permanently fixed in the same position in the sky, as viewed from a particular location on Earth.
3. GSLV Mk III is a four-staged launch vehicle with the first and third stages using solid rocket motors; and the second and fourth stages using liquid rocket engines.
Which of the statements given above is/are correct?
[UPSC Civil Services Exam – 2018 Prelims]
(a) 1 only
(b) 2 and 3
(c) 1 and 2
(d) 3 only
Answer: (a)
Explanation:
Statement 2 is not correct:
Satellites launched by GSLV appear to remain permanently fixed in the same position in the sky, as viewed from a particular location on Earth.
Statement 2 is not correct:
PSLV is a four-staged launch vehicle with the first and third stages using solid rocket motors; and the second and fourth stages using liquid rocket engines.
GSLV Mk III is a three-staged launch vehicle with 1st stage using solid rocket motor, 2nd stage using liquid fuel and 3rd stage using cryogenic engine.
