The Indian Space Research Organisation (ISRO) launched Earth Observation Satellite-8 (EOS-8) from the Satish Dhawan Space Centre in Sriharikota, Andhra Pradesh, on Friday.

In a post on X, the ISRO said, “The third developmental flight of SSLV was successful. The SSLV-D3 placed EOS-08 precisely into the orbit. This marks the successful completion of ISRO/DOS’s SSLV Development Project. With technology transfer, the Indian industry and NSIL India will now produce SSLV for commercial missions.”

According to ISRO, the six-and-a-half-hour countdown leading to the launch began at 2.47 am. This marks the third and final developmental flight of the SSLV-D3/EOS-08 mission. The spacecraft is designed for a mission duration of one year.

ISRO’s latest Earth Observation Satellite ‘EOS-08’, was launched by the Small Satellite Launch Vehicle (SSLV)-D3 at 9.17 am from the Satish Dhawan Space Centre in Shriharikota.

The primary objectives of the EOS-08 mission include designing and developing a microsatellite, creating payload instruments compatible with the microsatellite bus, and incorporating new technologies required for future operational satellites.

Built on the Microsat/IMS-1 bus, EOS-08 carries three payloads: Electro Optical Infrared Payload (EOIR), the Global Navigation Satellite System-Reflectometry payload (GNSS-R), and the SiC UV Dosimeter.

The EOIR payload is designed to capture images in the Mid-Wave IR (MIR) and Long-Wave IR (LWIR) bands, both during the day and night, for applications such as satellite-based surveillance, disaster monitoring, environmental monitoring, fire detection, volcanic activity observation, and industrial and power plant disaster monitoring.

The GNSS-R payload demonstrates the capability of using GNSS-R-based remote sensing for applications such as ocean surface wind analysis, soil moisture assessment, cryosphere studies over the Himalayan region, flood detection, and inland waterbody detection.

The SiC UV Dosimeter monitors UV irradiance at the viewport of the Crew Module in the Gaganyaan Mission and serves as a high-dose alarm sensor for gamma radiation.

The spacecraft mission configuration is set to operate in a Circular Low Earth Orbit (LEO) at an altitude of 475 km with an inclination of 37.4°, and has a mission life of 1 year.

The satellite has a mass of approximately 175.5 kg and generates power of around 420 W. It interfaces with the SSLV-D3 launch vehicle.

EOS-08 marks a significant advancement in satellite mainframe systems such as an Integrated Avionics system, known as the Communication, Baseband, Storage, and Positioning (CBSP) Package, which combines multiple functions into a single, efficient unit.

This system is designed with cold redundant systems using commercial off-the-shelf (COTS) components and evaluation boards, supporting up to 400 GB of data storage. Additionally, the satellite includes a structural panel embedded with PCB, an embedded battery, a Micro-DGA (Dual Gimbal Antenna), an M-PAA (Phased Array Antenna), and a flexible solar panel, each serving as key components for onboard technology demonstration.

The satellite employs a miniaturised design in its Antenna Pointing Mechanisms, capable of achieving a rotational speed of 6 degrees per second and maintaining a pointing accuracy of ±1 degree.

The miniaturised phased array antenna further enhances communication capabilities, while the flexible solar panel incorporates a foldable solar panel substrate, a GFRP tube, and a CFRP honeycomb rigid end panel, offering improved power generation and structural integrity.

A pyrolytic graphite sheet diffuser plate, known for its high thermal conductivity of 350 W/mK, reduces mass and finds application in various satellite functions. Furthermore, the EOS-08 mission adopts a new method of integrating housekeeping panels using a hinge-based fixture, significantly reducing the duration of the Assembly, Integration, and Testing (AIT) phase.