A new satellite that is orbiting the Earth can create high resolution images of nearly any place on our planet using radar – and is powerful enough to penetrate the walls of buildings. Capella-2, designed by Capella Space, uses Synthetic Aperture Radar (SAR), which can view the Earth regardless of air visibility, cloud covering or time of day – and is the same technology NASA has used since the 1970s.
SAR shoots powerful radio signals to ‘illuminate’ a point of interest, and collects data on the echo of each pulse that bounces back, interpreting them to create a detailed image.
‘Ghost’ images that appear to show the inside of structures is due to the satellite beaming down its own signal, and not just collecting light, which sometimes allows it to penetrate structures.
The satellite is capable of 50cm x 50cm resolution imaging with its latest update called Spotlight mode that allows for long exposures up to 60 seconds over an area of interest (AOI), which results in ‘crystal clear’ imagery.
Capella is currently testing a single device, but has obtained contracts with government agencies, including the National Reconnaissance Office and the US Air Force.
But Capella insists that the technology can’t be used to spy on people in their homes, and although the radar waves can penetrate walls, they say they cannot image anything inside.
The company explains: ‘The technology uses radio waves, which are capable of traveling through walls (like cell phones and Wi-Fi).
‘But, as we know, even cell phone and Wi-Fi signals weaken as they move further away from a cellular tower or a Wi-Fi access point. Radar signals are the same: They can travel through walls, but are far too weak to image or see anything indoors.’