From an IRIN report published in AllAfrica. Story by Obinna Anyadike.

Satellite imagery is increasingly being used by human rights organisations to fact check claims that otherwise would be difficult to verify. It provides an additional dimension of evidence for investigators, IRIN reports.

This was true in the destruction of the Northeastern Nigerian town of Baga and nearby villages earlier this month. Satellites provided graphic evidence of the extent of the crimes by the Islamist extremist group Boko Haram.

There are a number of increasingly sophisticated commercial satellites available at relatively low cost that are democratizing use. In the case of Baga, (Josh Lyons of Human Rights Watch) looked up online what imagery of the town was available on the specified days, paid the European company Airbus just US $350 (thanks to HRW’s NGO discount), and had the package of images in his computer within two hours. If he had ordered bespoke coverage, tasking the satellite to photograph a specific area, that would have cost between $400 and $1,380 depending how rapidly it was needed.

“The barrier is not necessarily price, but the sufficient software and expertise to interpret the imagery,” Lyons told IRIN. To get around that problem, non-profit organisations like the American Association for the Advancement of Science provide human rights groups with analytical support. Amnesty International used the satellite firm DigitalGlobe to interpret their Baga images.

Computer software, with complicated algorithms and change detection models are usually needed to process and manage large numbers of satellite images. They can come in different spectral bands, including near-infrared — good for monitoring changes in vegetation health — as well as detecting evidence of fire damage, as in the case of Baga. New satellite systems use shortwave infrared to pierce clouds and dense smoke to reveal objects that would be hidden in traditional imagery — with resolutions as high as 31 centimeters per pixel…

…GPS, Google Earth and the George Clooney-funded Satellite Sentinel Project (SSP), were steps in the evolving revolution in human rights monitoring. Now new micro satellite constellations such as Planet Labs and Skybox, which will provide constant real-time observation of the planet, are touted by some as a way to not just document but also deter rights abuse.

Read more at  AllAfrica.