With these small, inexpensive satellites, "we'll eventually be able to see anything on the planet. Anything," said Chris Boshuizen, co-founder and chief technology officer at Planet Labs. "We'll be able to tell you what something looked like the day before, the day of and the day after an event."
Planet Labs was founded in 2010 by three scientists who worked at NASA. Mr. Boshuizen is Australian, while Mr. Marshall is British. The third, Robbie Schingler, is an American who is the company's chief operating officer. Like many tech entrepreneurs, all three grew tired of the conventional way things were built — in this case, space products.
For example, the cost of designing, building, launching and monitoring the government's Landsat satellite, which takes pictures of Earth from 480 miles up, is over $1 billion, according to the United States Geological Survey, which administers data from the satellite.
Breaking into a field dominated by big companies with long government contracts is tough to do. And doing it cheaply is even harder.
In designing their satellites, Planet Labs threw out things like propulsion systems, because of the high cost and weight. Instead, the satellites use commercial light sensors, accelerometers and motors to orient their cameras. Laptop batteries were chosen because a more expensive version cost too much. Plus, they fit inside the satellite's frame.
By making little machines that are often updated, Mr. Gillmore said, "we're building satellites with computers that are six months old. Lots of satellites have 10-year-old computers." Version nine, which is almost complete, cost about 35 percent less than the current version in space, and was made four times faster, he estimated.
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Should Boeing be worried ?Not yet, said James P. Lloyd, associate professor of astronomy and mechanical and aerospace engineering at Cornell University. Professor Lloyd said he believed the space market was big enough for expensive Boeing systems and cheaper alternatives from start-ups.
"Essentially anybody can do it, because a combination of miniaturization, simplification and availability of technology for building small satellites has made it accessible in a way that has never been before," he said.
Also, while Planet Labs can beat older competitors on price, those expensive features do matter, said David Friedberg, chief executive of Climate, an agricultural data analysis firm owned by Monsanto. Monsanto buys data from several older imaging satellites, he said, but is not a Planet Labs customer because it does not yet offer the infrared imagery needed to judge the health of plants. "Their real competition may be drones," he said.
Still, Mr. Marshall is confident that his fast and cheap method will hold its own.
"This is the rapid prototyping, like you see with software, taken into space," he said. "We can see rivers changing course. We can count individual trees."
—By Quentin Hardy and Nick Bilton of The New York Times