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Radar images from Europe's Sentinel-1a satellite have revealed the aftermath of the Nepal earthquake in unrivalled detail.

The information from the satellites has been transformed into an interferogram, which provides a colourful and highly detailed view of the Earth's land mass.

By comparing before and after images, scientists have discovered that an area 75 miles (120km) by 30 miles (50km) has lifted up 3.2ft (1 metre) from the ground around the capital, Kathmandu.

Interferogram over Kathmandu, Nepal, generated from two Sentinel-1A scans on 17 and 29 April 2015 – before and after the 25 April earthquake. Each 'fringe' of colour represents about 3cm of deformation. The large amount of fringes indicates a large deformation pattern of 3.2ft (1 metre) from the ground around Kathmandu

These are the first radar images to reveal the destruction caused by the 7-magnitude earthquake that killed 5,000 people and affected millions more.

'There's a peak of slip just to the northeast of Kathmandu,' Professor Tim Wright from the Natural Environment Research Council told the BBC.

He explained that what scientists count are the coloured 'fringes' in the interferogram, of which there are about 34 from this quake. This translates to more than 3.2ft (1 metre) of uplift.

To the north of Kathmandu, the interferogram suggests that the ground receded, and it also shows how a fault ruptured east from the epicentre, but did not break the surface.

Combining two Sentinel-1A radar scans from 17 and 29 April 2015, this interferogram shows changes on the ground that occurred during the 25 April earthquake that struck Nepal. An overall area of 120x100 km has moved – half of that uplifted and the other half, north of Kathmandu subsided. Vertical accuracy is a few centimetres

Sentinel-1A interferogram over Kathmandu, Nepal, showing deformation induced by the 25 April 2015 earthquake. East–west 'fringes' cross the city, with each coloured fringe corresponding to 2.8 cm of ground displacement (both uplift and subsidence). The interferogram combines two Sentinel-1A images from 17 and 29 April 2015

Professor Wright says this suggests not all the strain in the rocks before the earthquake was released in during the catastrophic event.

Sentinel-1A's swath width of 155 miles (250km) over land surfaces has allowed for an unprecedented area size to be analysed from a single scan.

Scientists say the entire area will be covered under the same geometry every 12 days, allowing for the wider region to be regularly monitored for changes in the land.

Its ability to 'see' through cloud and rain and in pitch darkness make it particularly useful for monitoring earthquakes and for offering images for emergency response.

This is because it uses radar which works by sending out radio waves and timing how long it takes for them to reflect back.

Radio waves travel through air virtually unimpeded, but materials like metal, rock and water act almost as mirrors which can help reveal those areas inundated by floods. It also makes no different to radar if the Earth is in darkness.

Sentinel-1A is the first satellite for the Copernicus environment-monitoring programme led by the European Commission. 

The Copernicus EMS was activated on the day the earthquake struck, prompting Esa to begin collecting satellite imagery, which is being made available to support relief efforts. In parallel, the International Charter Space and Major Disasters was activated by India, China and the UN. 

Meanwhile, Nasa has posted its own images of the earthquake providing much less detail due to cloud cover. 'While we regularly post imagery of natural hazards, the weather and the satellites haven't cooperated in this case,' the space agency wrote in a blog. 

'The orbital track of the satellites and the specific capabilities of the sensors on board determine whether we have imagery to share. In the case of Nepal, things haven't lined up in our favour.'

The satellite imagery is used to create maps to support relief efforts, such as this 'grading map' of Kathmandu showing topographic features and crisis information. The red squares show road blockss, the green people markers show crowds, red dots are areas that are destroyed and yellow dots are areas that are possibly affected. The yellow lines mark out primary roads in the area

Sentinel-1 carries a radar that works in several specialised modes to provide detailed imagery (artist's impression left). The data will be used for applications such as monitoring the oceans, including shipping lanes, sea ice and oil spills. It also provides data to map changing land cover and deformations such as those produced by Saturday's devastating Earthquake in Nepal (right)

Mount Everest before and after the earthquake. Not much change is visible because of a fresh coat of snow and cloud cover. The April 23 image was acquired by the Operational Land Imager on Landsat 8

Nasa has posted its own images of the earthquake providing much less detail due to cloud cover. 'While we regularly post imagery of natural hazards, the weather and the satellites haven't cooperated in this case,' the space agency wrote in a blog