Deep Space Industries (DSI) has secured a contract to provide its Comet water-based satellite propulsion systems for Spaceflight Industries’ BlackSky constellation of Earth observation smallsats.

As part of the deal, DSI will initially provide a set of 20 water thrusters for the BlackSky satellites, which are expected to begin launching later this year.

The deal follows Spaceflight Industries’ recently announced $150m funding and the formation of the LeoStella joint venture with Thales Alenia Space.

LeoStella is set to develop a facility in Seattle, US, to manufacture the BlackSky satellites. It is expected to build 20 BlackSky spacecraft with Comet propulsion technology until 2020.

“The launch-safe propulsion features of the Comet system are well aligned with BlackSky’s performance needs to enable affordable and flexible satellite systems.”

Following their launch, the BlackSky smallsats will form an ultimate constellation of 60 satellites that will provide high revisit rate Earth imagery.

In combination with other space-based sensors, the satellites will be able to provide innovative global monitoring solutions and geospatial activity-based intelligence services.

Spaceflight Industries space operations vice-president Nick Merski said: “The launch-safe propulsion features of the Comet system are well aligned with BlackSky’s performance needs to enable affordable and flexible satellite systems.”

DSI’s Comet satellite propulsion system represents the company’s first set of green propulsion solutions developed for small satellites.

Unlike other propulsion systems that use either high-pressure or toxic propellants, Comet systems are designed to be low-pressure, non-toxic, and offer safe satellite launches.

Comet offers a ride-share capability and can be customised for many mission types and sizes.

DSI has long-term plans for developing propulsion systems that use propellants sourced from space.