BlueBird Block-2 Satellite
Context:
ISRO recently launched the LVM-3 rocket carrying its heaviest-ever satellite, the BlueBird Block-2.
Weighed at nearly 6,100 kg, this mission marks a significant milestone in India's commercial space capabilities
About the BlueBird Block-2 Satellite:
BlueBird Block-2 is a commercial communications satellite and represents the heaviest single satellite payload ever launched by ISRO
It is designed by US-based AST SpaceMobile and is part of a Low Earth Orbit (below 1000kms) constellation intended to provide direct-to-mobile connectivity
Unlike conventional satellites that beam signals to ground stations, this constellation communicates directly with mobile phones, enabling 4G/5G voice, video, and data for everyone, everywhere
About LVM3-M6 Launch vehicle:
LVM-3 is ISRO’s heaviest and most powerful launch vehicle
In its earlier missions, LVM3 successfully launched Chandrayaan-2, Chandrayaan-3, and two OneWeb missions carrying 72 satellites.
Though originally designed to place satellites into geosynchronous transfer orbits (GTO) (~36,000 km), LVM-3 is now used for LEO missions, especially heavy payloads.
Cryogenic Engine in LVM-3:
Cryogenic engine is used in the third (upper) stage of LVM-3, known as the C25 stage.
It uses cryogenic propellants:
Liquid Hydrogen (LH₂) as fuel
Liquid Oxygen (LOX) as oxidiser
ISRO plans to replace the liquid propellant second stage with a refined kerosene and liquid oxygen (Semi-Cryogenic) engine which would boost the carrying capacity of LVM-3 to LEO to 10,000 kg.
The cryogenic stage contributes nearly 50% of the rocket’s total velocity, enabling heavy payload insertion into LEO and GTO.
LVM-3 is the designated launch vehicle for the Gaganyaan mission.
The vehicle is central to India’s future human spaceflight ambitions, including the proposed Bharatiya Antariksh Station.
Significance:
This launch positions ISRO as a cost-effective alternative to heavy launch providers (like SpaceX’s Falcon-9 and ESA’s Ariane 6)
It also marks the shortest gap between two LVM-3 launches, demonstrating ISRO's ability to quickly assemble heavy missions.