Exhibition 'The Call of the Mountains' opens at the Gasometer Oberhausen
- Focus: Space, Earth Observation
At 4478 metres tall, the Matterhorn is not one of Earth's highest mountains – not even the highest mountain in the Alps. However, its striking triangular shape makes it unique. The German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR) has measured this 'rock pyramid' with the help of satellite and aircraft overflights and, from the data, generated a precise terrain model that now brings the mountain to Gasometer Oberhausen as a 3D projection on a 17-metre-high reproduction of the Matterhorn. There, it floats upside down in the 100-metre-high airspace of the Gasometer as the highlight of the exhibition 'The Call of the Mountains', which was inaugurated on 16 March 2018. A mirror on the floor reflects the mountain, enabling a bird's eye view.
Over flanks and snow fields
Just under 3000 images provided the foundation to construct the animation, which was done by the scientists at DLR's Earth Observation Center (EOC). To collect them, a Pléiades satellite recorded the Matterhorn for a few seconds from three different angles during one overflight. These data were supplemented with measurements made from DLR's twin-engine DO 228 research aircraft. With the 3K camera developed at DLR the researchers photographed the mountain from all sides with its 2000-metre steeply falling flanks and continuous alternating bright snow surfaces and dark shadows. With the help of an algorithm that originally gave robots spatial vision at DLR, the images were used to produce a three-dimensional terrain model of the mountain. On the computer at the Earth Observation Center DLR scientists combined the acquired elevation data and textures into a likeness of the Matterhorn. They then had hundreds of virtual cameras circle the mountain to produce 3D animations that brought the sculpture to life. At 67 million pixels, the resolution of the animation is eight times that of a high-resolution film production.
"The expertise used to produce the Matterhorn sculpture for the 'The Call of the Mountains' exhibition is put to work on a daily basis in the course of our Earth observation activities", says Hansjörg Dittus, DLR Executive Board Member responsible for Space Research and Technology. "With remote sensing from space we provide and process data to monitor and investigate changes to Earth's surface and atmosphere, as well as global change. For us, the Matterhorn project was a testbed for trying out and evaluating our methodologies."
The Matterhorn challenge
Emergency support workers, city planning authorities, climate researchers and also archaeologists are the usual beneficiaries of Earth observation. Data from space can be used for numerous applications – among others it can be employed to record ground movement with millimetre accuracy, investigate the quality of water, or estimate glacier masses. Now, viewers of 'The Call of the Mountains' exhibition can also find out how Earth observation data is used.
"On the projection surface we show the Matterhorn with the progression of days and seasons, the ascent routes that mountaineers have opened up over the course of 150 years, and the extreme topography of the mountain," explains Nils Sparwasser of DLR's Earth Observation Center. "To do this we have to record, process and analyse large amounts of data – which we are of course well able to do." With this elaborate animation, 17 projectors display the details on the 2033 square metre surface of the Matterhorn reproduction.
But the exhibition at the Gasometer Oberhausen does not only present the Matterhorn. In unique film excerpts and photographs, it shows habitats at ice-cold altitudes with thin air, helps visitors appreciate the legendary first ascents, and reports about triumphs and failures. "In ‘The Call of the Mountains’ we describe wonderful locations that have always fascinated mankind", says Peter Pachnicke, curator of the exhibition.