On the 30th of July 2023, India launched the PSLV rocket from Satish Dhawan Space Centre, carrying seven satellites from Singapore. The payloads for the rocket were: DS-SAR, ARCADE, VELOX-AM, SCOOB-II, ORB-12 STRIDER, Galassia-2, and NuLIoN. The combined weight of the satellites was 422.5 kilograms, and was placed into a 535km circular orbit on a five-degree orbital inclination.

Launch video via ISRO's Twitter account.

What are the payloads?

DS-SAR is the primary payload of the launch and was developed under a partnership between DSTA (representing the Government of Singapore) and ST Engineering. Once deployed and operational, it will be used to support the satellite imagery requirements of various agencies within the Government of Singapore. ST Engineering will use it for multi-modal and higher responsiveness imagery and geospatial services for their commercial customers.

VELOX-AM is a microsatellite developed by Nanyang Technological University (NTU), Singapore, for technology demonstration of Additive Manufacturing (AM) payloads.

ARCADE is a 27U microsatellite designed and built by Nanyang Technological University (NTU), Singapore, in collaboration with the INSPIRE (International Satellite Program in Research and Technology) consortium. ARCADE carries an iodine-based solid propellant propulsion module, based on a Hall effect thruster for orbit maintenance during the low altitude mission.

SCOOB-II is a 3U CubeSat designed and developed by a student team at Satellite Research Centre (SaRC), Nanyang Technological University (NTU) in Singapore. The satellite is designed for a 6-month mission lifetime. SCOOB-II utilizes a three-axis controlled reaction wheel assembly for attitude control.

NuLIoN is a 3U nanosatellite developed by NuSpace as the seed satellite for a LEO equatorial constellation providing continuous LoRaWAN IoT services.

Galassia-2 is an educational 3U nanosatellite by National University of Singapore (NUS). The main mission of GALASSIA-2 is to perform an inter-satellite link (ISL) with TeLEOS-1. Galassia-2 will demonstrate the capability of using Commercial Off The Shelf (COTS) multispectral imagery for space applications.

ORB-12 STRIDER is developed under an international collaboration, coordinated by Singapore-based ALIENA, including Orbital Astronautics as bus providers, and Aurora Propulsion Technologies as subsystem co-developers. It will demonstrate next-generation propulsion systems catered specifically for small satellite constellations. ORB-12 STRIDER will carry the world’s first Multi-modal all-Electric Propulsion Engine (MEPE), featuring ALIENA’s flagship Multi-Stage Ignition Compact (MUSIC) Hall thruster and Aurora’s ARM resistojets.

PSLV on the launch pad at Satish Dhawan Space Centre.

What is PSLV?

The Polar Satellite Launch Vehicle, commonly referred to as PSLV, is a four-stage medium-lift launch vehicle that has launched fifty-eight times with fifty-five successes. PSLV first flew on the 20th of September 1993 and was developed so India could launch its remote sensing satellites into sun-synchronous orbit but is now a leading provider of small satellite rideshare services.

The first stage is a twenty-meter tall solid rocket booster generating 494 tons of thrust burning Hydroxyl-terminated polybutadiene for 110 seconds. The first stage can have up to six boosters attached generating 72 tons of thrust each for 70 seconds. The second stage is powered by a single Vikas engine generating 82 tons of thrust for 133 seconds burning Dinitrogen tetroxide and Unsymmetrical dimethylhydrazine. The third stage is a three point six meter tall solid rocket motor generating 25 tons of thrust for 113.5 seconds burning Hydroxyl-terminated polybutadiene. The fourth stage is powered by two L-2-5 engines burning Monomethylhydrazine and Mixed oxides of nitrogen for up to 525 seconds generating 1.5 tons of thrust.