Capella Space Raises $19M Series B: Satellite Swarms with Synthetic Aperture Radar for Continuous Whole-Earth Imaging

by Matt Ocko and Nabeel Hyatt

Today DCVC and Spark Capital are proud to announce co-leading the Series B in Capella Space, as they continue their mission to revolutionize the world of satellite imaging. As long time partners in Capella, we’ve seen first hand the breakthroughs this team has continued to deliver as they now sit on the verge of launching the first U.S. commercial synthetic aperture radar ever.

We invested in Capella because of the dramatic cost decrease achieved through their compact satellite design — at least a 98% reduction compared to traditional satellites. This low cost means that Capella can launch enough satellites to map any part of the Earth’s surface, every hour, in 1-meter resolution or higher. Synthetic Aperture Radar outperforms traditional satellite imagery because it accurately maps objects a) in the dark, b) in poor weather conditions, and c) up to 3 meters underground if configured in certain bands, allowing for the detection and monitoring of pipes, tunnels, mines, and more. This cost decrease, data quality increase, and imaging frequency increase will make satellite imagery accessible and useful in many new applications: from governments fighting illegal fishing to individual farmers trying to gauge their crops’ health.

Synthetic Aperture Radar was invented in the 1950s by Carl Wiley, an engineer working at Goodyear Aircraft (now part of Lockheed Martin). He found that — because each object in a radar beam has a slightly different speed relative to the antenna — detailed images can be reconstructed from a precise frequency analysis of radar reflections.

By the end of the 1960s, US government SAR systems could map terrain at a high resolution, as much as 1 foot, and scientists had developed foliage-penetrating SAR that could distinguish enemy structures in forested areas. In the 1970s, the National Oceanic and Atmospheric Administration and NASA’s Jet Propulsion Laboratory launched the first SAR-enabled satellite — Seasat — to make oceanic and environmental observations.

But building and launching SAR-enabled satellites has been prohibitively expensive for all but the richest governments, which means that many of the satellites in orbit today are used for government reconnaissance. For instance, the US Lacrosse satellites, operated by the National Reconnaissance Office, are estimated to have cost somewhere between $500 million and $1 billion apiece. That’s a total price tag of $2.5 to $5 billion for the 5 known satellites in the program. The actual cost could be much higher.

SAR satellites’ high price tags are partly due to their size and weight. Modern SAR satellites — like the TerraSAR — are about 2.5 meters across and 4 to 5 meters tall, and weigh more than 1,000 kilograms (2,200 pounds). Launching such a large payload is expensive, but satellite size and weight have been difficult to decrease because SAR systems need large antennae to take accurate images of the Earth, and those large antennae also have equally large solar power requirements

SAR antennae are what the satellites use to send microwave pulses at the surface of the Earth, thousands of times per second. These waves are able to reach the Earth’s surface regardless of weather or what time of day it is, unlike the optical waves (light) that traditional satellite imaging depends on. When these pulses hit the Earth, a portion of them backscatter toward the satellite, where a receiver picks them up. SAR systems can create such high-resolution images because the moving satellite is able to read the backscattered pulses from multiple angles. The larger the antenna size, the more angles are recorded, which gives the images higher resolution over a given timeframe. The receiver records how long each pulse took to reach the Earth and return, how strong the pulse is compared to when it left, and how much the phase of the signal changed with the trip (see diagram). The satellite sends this information back to its base station on Earth, where computers use it to reconstruct a detailed image of the landscape the microwaves bounced off of. These slight variations can also carry information about the material properties of what they bounce off of, like moisture levels in a field.

The last few years in satellite innovation have been marked by a rapid increase in the deployment of smallsats, which drastically reduce the form factor of a satellite to the size of backpack. Those smaller payloads allow for the a drastic reduction in imagery costs, which expand usage in current satellite imaging markets, and open up new markets.

SAR satellites, because of their massive antennae and power needs, do not easily lend themselves to being constructed in a smallsat format. Capella has created a breakthrough to keep the SAR’s large antenna — without the school bus-sized spacecraft — by using a flexible, foldable material for antenna design, miniaturizing the satellite’s hardware elements, and designing an innovative heat dissipation subsystem to keep the satellite running smoothly. The end result is a satellite a fraction of the cost and weight of traditional systems that provides superior coverage and reliability. These advancements are further compounded by the falling costs of orbital launches, which Capella is using to their full advantage. Their first launch in November will be on a SpaceX Falcon 9 rocket — one of the most competitive options for orbital launches. Delivering this low-cost spacecraft in a low-cost manner makes it even easier to scale.

SAR has traditionally been used for military and reconnaissance purposes, but the cost decreases Capella brings will spur its adoption in new industries, including environmental monitoring, agriculture, oil spill tracking, disaster relief, urban planning and much more. The cost has been so prohibitive that until Capella there has not been a single U.S. commercial company that has launched a SAR satellite, and we’re excited to see how this new source of information will transform industries. Congratulations to the Capella Space team on the progress they’ve made so far and promise of their upcoming launches.