Planet sees our planet —

Satellite images from highly oblique angles are pretty mindblowing

"I thought it would be great to take some imagery of the world’s most vertical places."

Founded in 2010 by three former NASA scientists, Planet Labs has been among the forefront of several companies seeking to provide high-quality, commercially available imagery of planet Earth. As such, it has the capability to look all around the world, in real time.

In January, a senior data visualization engineer at the company began to survey the damage from mudslides in Southern California. As Robert Simmon looked at the area, which had been ravaged first by wildfires and then large debris flows, he realized he could not see all that much definition between the flat, coastal area and the nearby San Rafael and Santa Ynez mountain ranges. "The entire sense of mountain terrain was lost," Simmon told Ars.

Most traditional satellite images show great detail about the Earth's surface, but as they observe from directly overhead, this vantage point makes the planet look flat. Of course with hills, valleys, mountains, and cities, the surface is anything but flat. So Simmon began fiddling with some of Planet's satellites, including its 13 SkySats orbiting at 450km above the Earth's surface that have a resolution of 80cm per pixel. Instead of taking overhead images, Simmon began to capture images from highly oblique angles—as much as a 60- or 70-percent difference from directly overhead images.

"I thought it would be great to take some imagery of the world’s most vertical places," he said. (Some of the results appear in the gallery above.) "The reason I put these together is because it provides a much more human viewpoint," Simmon said. "It provides a much better view of the landscape, allowing you to reconstruct the terrain in your mind."

There are some potential applications, too, beyond the "wow" factor of the images. Taking stereo images of an object from different angles will allow for the derivation of height. And taking images from many different angles will allow for the construction of a 3D model of a mountain or be used to track urban growth in cities.

There is even enough resolution in the SkySat images for commodity traders to track the volumes of coal at a site, the depth of mines, or even to determine the height of shipping containers to measure the outflow of goods from a port.

Listing image by Planet Labs, Inc.

Channel Ars Technica