Isro successfully launches SSLV-D3: Why is this mission significant for India’s space sector?

The Indian Space Research Organisation (Isro) on Friday morning successfully launched its third development flight of the small satellite launch vehicle (SSLV).

The vehicle is carrying the 175-kilogramme Earth Observation Satellite-8 (EOS-08) on board, according to the space agency.

The launch took place from the Satish Dhawan Space Centre in Andhra Pradesh’s Sriharikota at 9.17 am.

Following the launch, Isro said in a post on X, “The third developmental flight of SSLV is successful. The SSLV-D3 placed EOS-08 precisely into the orbit.”

The SSLV development project by Isro has been completed with SSLV-D3.

Here’s all we know about it.

The SSLV-D3

The small rocket is just two metres in diameter and 34 metres long and weighs 120 tonnes, as per NDTV.

It can carry satellites weighing up to 500 kilogrammes and place them in Low Earth Orbit (up to 500 kilometres above Earth).

By contrast, the Bahubali, also known as the Geosynchronous Satellite Launch Vehicle (GSLV Mk 3) is India’s biggest rocket, weighing 640 tonnes, according to the report.

The mini rocket was developed by Isro with the aim of commercialising it.

The SSLV took more than seven years to build and was ready for a total cost of more than Rs 170 crore, in keeping with Isro’s goal of launching affordable yet successful space missions.

According to Swarajya magazine, almost 21 new technologies are being tested for this launch, according to Isro.

Dr M Sankaran, Director of the UR Rao Satellite Centre (URSC), as per the magazine said, “It is a trailblazing satellite packed with new futuristic technologies. The small 175 kilogrammes, EOS-8 satellite is packed with new and novel experimental technologies that will help power Isro’s and India’s dreams.”

The launch is special

According to space scientists, the SSLV is a three-stage rocket, with solid propellant powering the first three stages.

The last stage, the terminal stage, has a payload adapter and a liquid propulsion system known as the Velocity Trimming Module (VTM), explained The Week.

The payload adapter firmly fastens the payloads to the rocket’s top, guaranteeing their safe delivery into space, and the VTM is utilised to change the rocket’s speed as needed.

To generate thrust, the VTM modifies by releasing tiny volumes of liquid fuel. With this thrust, the rocket’s velocity may be precisely controlled by increasing or decreasing its speed. With this, the VTM assists in directing the rocket into the desired orbit.

“The SSLV can be launched quickly when needed, allowing Isro to serve the growing market for small satellite launch services efficiently. This launch vehicle can send one satellite weighing up to 500 kg into a planar orbit, 500 km above the Earth and is capable of conducting six to eight missions each year,” said space expert Girish Linganna, as per the report.

Commercialising SSLV

According to Indian Express which cited Isro officials, this is the final SSLV mission that Isro will launch; after that, all missions will be executed by the selected commercial business. The technology is already up for acquisition by a minimum of six companies.

An MoU was signed by Isro’s commercial division, New Space India Limited (NSIL), to launch an Australian satellite aboard a commercially operated SSLV in the future. The Australian company Space Machines Company is planning to launch a satellite into space that can repair other satellites while they are in orbit.

Isro Chairperson Dr S Somanath stated, as per NDTV, “By its sheer simplicity and production friendliness, SSLV will be a game changer in the industry production and launch goal for commercial launchers of India.”

The need for small launch vehicles that can be rapidly built on demand to launch numerous small and microsatellites into low earth orbit is increasing on a global scale.

Although Isro does not release precise costs, analysts project that each SSLV launch will come with a price tag of approximately Rs 30-35 crore, placing it among the most reasonably priced rockets in its class.

The global small satellite market is expected to reach $13.71 billion by 2030, from an estimated $3.25 billion in 2020, according to a Bloomberg report. Thus, the commercialisation of SSLV holds great promise.

“The SSLV is designed to be a cost-effective choice for launching into space. It offers the flexibility to carry multiple satellites and can be ready to launch quickly. The SSLV requires minimal infrastructure, has a short turnaround time, and can be built faster by industries. It also requires very little time at the launch pad, allowing integration and launch within 24 hours,” said Linganna, as per The Week.

EOS-08 and its advanced payloads

The EOS-08 satellite is designed to enhance environmental monitoring, facilitate the management of natural disasters, and assist with the Gaganyaan mission.

It is constructed on a regular Isro Microsat/IMS-1 bus. It is equipped with three instruments: The Electro Optical Infrared Payload (EOIR) is intended to take daytime and night time mid-wave and long-wave infrared photos.

In satellite mainframe systems, the EOS-08 offers numerous new technological advancements. These include the Communication, Baseband, Storage, and Positioning (CBSP) package, an integrated avionics system that may combine several tasks into a single, effective unit that supports up to 400 GB of data storage, reported CNBC-TV18.

According to the space agency, it also features a flexible solar panel and a nanostar sensor for onboard technology demonstration.

The previous two developmental flights of SSLV

On August 7, 2022, the Microsat 2A and AzaadiSAT satellites were launched on SSLV’s maiden developmental mission.

However, a sensor failure that escaped the attention of the ground control staff prevented it from successfully putting the satellites into their planned circular orbit, as per The Week.

On February 10, 2023, the second SSLV development flight, or SSLV-D2, was launched.

The EOS-07 (Earth Observation Satellite-07), Janus-1, and AzaadiSAT-2 satellites were successfully launched into an orbit 450 kilometres above Earth during this mission.