Microsatellites and Small Satellite Technologies

Small satellites have changed the economics of space missions by making them faster, cheaper and easier to launch. Microsatellites and nanosatellites are now widely used for Earth observation, communications, scientific experiments and space surveillance. Their compact size allows multiple satellites to be deployed in constellations for frequent coverage and flexible mission design.

Classification of Small Satellites

The space industry generally classifies satellites by wet mass. Small satellites, or smallsats, weigh less than 500 kilograms and are divided into several standard categories. These mass bands matter because they determine payload design, launch options and mission complexity.

• Smallsat advantage: they provide a cost-effective alternative to large conventional satellites, especially for low Earth orbit missions.
• Constellation-friendly: smaller spacecraft can be launched in groups to improve coverage and revisit frequency.
• Rapid deployment: standardized designs reduce the time between concept, fabrication and launch.

CubeSat Standard and Design Features

CubeSats are a highly standardized nanosatellite format built in modular units called U. A single unit is a cube of 10 cm × 10 cm × 10 cm and typically weighs around 1.33 kilograms. Developers often combine units into 3U, 6U, 12U or 24U configurations, depending on mission needs.

• Standardisation: the CubeSat form factor allows common mechanical and electrical interfaces.
• COTS components: many missions use Commercial Off-The-Shelf electronics, reducing cost and development time.
• Secondary payloads: small satellites are often launched alongside larger satellites through rideshare missions.
• Canister deployers: standard deployment systems improve launch safety and simplify integration.

Core Technologies and Subsystems

The success of small satellites depends on the miniaturisation of key subsystems without losing mission reliability. Advances in microelectronics, sensors and onboard computing have made this possible.

• Optical payloads: miniature cameras and multispectral sensors support high-resolution Earth observation from low Earth orbit.
• Inertial navigation units: MEMS-based gyroscopes and accelerometers help with attitude determination and control.
• Onboard data processing: edge-computing payloads can process data in orbit, reducing downlink requirements.
• COTS electronics: industrial-grade processors offer higher computational power at lower cost, though radiation tolerance remains a challenge.
• Miniaturised communications: compact transmitters and inter-satellite links support data relay across a constellation.

Small satellites are not just smaller versions of large satellites; they are designed for rapid deployment, distributed operations and lower mission cost.

Launch Ecosystem and Indian Framework

The growth of small satellites has encouraged dedicated launch systems and a more flexible commercial framework. India has positioned itself strongly in this segment through launch capability and regulatory support.

• SSLV: the Small Satellite Launch Vehicle developed by ISRO is a three-stage all-solid launch vehicle.
• Launch capacity: SSLV can place about 500 kg into a 500 km planar orbit.
• Launch-on-demand: it is intended for quick and flexible deployment of small satellites with minimal infrastructure.
• NSIL: NewSpace India Limited serves as ISRO’s commercial arm and supports commercial use of launch vehicles such as SSLV and PSLV.
• IN-SPACe: the Indian National Space Promotion and Authorization Centre functions as a single-window nodal agency for authorising private space activity.
• Rideshare launches: these reduce launch cost by sharing rockets among multiple satellite users.

Applications in Earth Observation, Security and Connectivity

Small satellite constellations are increasingly important in civilian, strategic and commercial domains. Their main strength lies in frequent revisit times and the ability to distribute functions across many satellites.

• Earth observation: they support crop assessment, disaster mapping, urban monitoring and environmental studies.
• Space situational awareness: microsatellite systems can track active satellites, defunct spacecraft and debris to reduce collision risk.
• Defence applications: high revisit rates help with border monitoring, maritime surveillance and time-sensitive situational awareness.
• Synthetic Aperture Radar (SAR): small satellites equipped with SAR can help generate detailed surface information and elevation models.
• Data relay: inter-satellite links improve communication continuity and reduce dependence on a dense ground network.
• Innovation platform: the segment encourages experimentation by startups, universities and private manufacturers.

India, France and the Commercial Push

India and France have a long-standing space partnership built on cooperation between ISRO and the French space agency, CNES. This collaboration now extends to private companies and the small satellite market.

• Safran Space-Dhruva Space: France’s Safran Space signed contracts worth over EUR 5 million with India’s Dhruva Space for communication systems, inertial navigation units, optical payloads and ground stations.
• SBS-III constellation: the supplied technologies are intended for integration into India’s planned space-surveillance constellation, projected to deploy 52 satellites between 2027 and 2030.
• RIDE!-TakeMeToSpace: the French launch-services provider signed an agreement to launch two satellites for TakeMeToSpace, an Indian developer of orbital data centres.
• AXISCADES-U-Space: the two firms signed a commercial cooperation agreement to explore India’s microsatellite market under a phased roadmap aligned with the Make in India policy.
• Broader trigger: these agreements were announced during the International Space Summit on September 9–10, 2026.

Key Prelims Takeaways

• Small satellite definition: satellites with mass below 500 kg are generally treated as small satellites.
• Microsatellite range: microsatellites fall in the 10 kg to 100 kg band.
• Nanosatellite range: nanosatellites weigh 1 kg to 10 kg; CubeSats are a major sub-class.
• CubeSat unit: 1U equals 10 cm × 10 cm × 10 cm and typically weighs about 1.33 kg.
• Cost efficiency: small satellites reduce mission costs through standardisation, rideshare launches and COTS components.
• SSLV role: India’s SSLV is designed for quick, flexible launch of small payloads into low Earth orbit.
• Space security use: microsatellite constellations are increasingly used for space situational awareness and defence-related monitoring.

Recent Context

During the International Space Summit in Paris on September 9–10, 2026, Indian and French private space entities signed three agreements covering satellite launches, space surveillance and microsatellite technology. The deals included support for India’s SBS-III constellation, launch services for orbital data centres and a commercial push into the microsatellite market.