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Imaggeo

Imaggeo on Mondays: Watching the world from space with EarthKAM

Imaggeo on Mondays: Watching the world from space with EarthKAM

This photo was taken from the International Space Station (ISS), approx. 400 km above the Earth, in the NASA-led educational project Sally Ride EarthKAM (www.earthkam.org), Mission 58, April 2017. The image was requested by a team of 10th and 11th grade students from the National College of Computer Science, Piatra-Neamț, Romania, coordinated by me. The lenses used on the digital camera mounted on the ISS are 50 mm focal length. The area photographed is a region of 185.87 km wide and approx. 123.5 km long, from Utah, USA. The view is spectacular, a perfect equilibrium between mountains, canyons, lakes and bays.

It’s just one of the pictures that my students had the opportunity to get from the ISS. Even though we weren’t there on the ISS to trigger the camera, all the locations in which the photographs were taken were chosen by us, on the track of the ISS.

The project activities were very complex. The students learned about the Earth, its rotation and gravity, and about the space station and its orbit. They completed their knowledge of physics, understanding how from the ISS orbit we can have another perspective of the Earth. They chose the places on the Earth to be photographed, studied these regions and monitored the weather conditions for better photo opportunities. They identified the places on Google Earth, analysed the photos and then created QR codes for some of them.

Below are the QR codes for the photo “Awesome trip above the Earth”:

 

The ISS became an innovative learning environment for the students. The astronauts’ availability for engaging in educational programmes, sharing their extraordinary experiences of becoming aware of the beauty and fragility of the Earth from the ISS orbit, has increased the attractiveness of learning about space. As Sally Ride, the first American astronaut woman on the ISS, said:

“When I was orbiting Earth in the space shuttle, I could float over to a window and gaze down at the delicate white clouds, brilliant orange deserts, and sparkling blue water of the planet below. I could see the coral reefs in the oceans, fertile farmlands in the valleys, and twinkling city lights beneath the clouds. Even from space, it is obvious that Earth is a living planet.”

The photo was integrated into a photo exhibition called “The Earth’s Colors” that I realised with my students at my college, which led the viewer on a global trip, discovering how beautiful and fascinating the Earth viewed from Space is. Satellite photography offered my students a new world perspective, encouraging them to ask questions and to search for the answers. It was a new and exciting way to travel and discover our planet.

The project was a great opportunity, not only for my students but also for thousands of other students around the globe, to study the Earth in a way that complements different subjects in order to better understand our world. It also has strengthened my conviction that, as the teacher and Challenger astronaut Christa McAuliffe said:

“…space is for everybody. It’s not just for a few people in science or math, or for a select group of astronauts. That’s our new frontier out there, and it’s everybody’s business to know about space.”

By Diana Cristina Bejan, physics teacher, The National College of Computer Science, Piatra-Neamț, Romania

Imaggeo is the EGU’s online open access geosciences image repository. All geoscientists (and others) can submit their photographs and videos to this repository and, since it is open access, these images can be used for free by scientists for their presentations or publications, by educators and the general public, and some images can even be used freely for commercial purposes. Photographers also retain full rights of use, as Imaggeo images are licensed and distributed by the EGU under a Creative Commons licence. Submit your photos at http://imaggeo.egu.eu/upload/.

Imaggeo on Mondays: On the way to Tristan’s penguins

Imaggeo on Mondays: On the way to Tristan’s penguins

Tristan da Cunha is a remote volcanic island in the south Atlantic Ocean. In fact, it is the most remote inhabited archipelago in the world. Tristan is still volcanically active; the last time it erupted was in 1961. After the eruption, which luckily did not have any casualties, the whole population of around 260 people evacuated the island for some time, but they all returned back to the island because it was home.

I took this photo while aboard the ISOLDE research cruise associated with the GEOMAR Helmholtz Centre for Ocean Research in Germany. The ISOLDE project focuses on investigating the electromagnetic, gravimetric and seismic activity present on this little island.

There are several reasons why this area is particularly interesting for multi-disciplinary geophysical studies. First, the island is a prominent candidate for a deep-rooted hot spot. A hot spot is a volcanic region believed to be fed by mantle plumes, which bring considerable heat from deep in the Earth. Deploying ocean bottom seismometers (OBS) should help investigate the presence (or absence) of a whole-mantle plume beneath the island. Second, geophysical analysis in this region can help scientists better understand the tectonic processes involved in the extension of the South Atlantic margins and the formation of the Walvis Ridge.

In 2012, the ISOLDE (as part of the SAMPLE project) research cruise aimed to acquire a year’s worth of data on the marine electromagnetic activity, active and passive seismicity, gravity and bathymetry around Tristan da Cunha. Among others, there were 24 OBS deployed on the sea floor (around 3000-4000 m in depth). These instruments stay on the ocean bottom for one year and continuously record seismic signals.

After one year, in 2013, I joined the recovery cruise. This was my second time on a research vessel, but it was the first time I actually worked as a technical assistant on OBS.

The cruise started from Walvis Bay, a coastal town in Namibia. After a one-week transit from the harbour to the first station, we spent around seven days recovering 12 OBS around Tristan da Cunha.

The process of recovering the instruments is usually straight forward. To start, you head to the location where you first deployed the instrument, put a transducer into the water and then ping the OBS. If you get a response, you enter a code that sends an acoustic signal to release the main instrument from its steel anchor. The floating units attached to the instrument then take care of bringing the OBS back to the sea surface. Depending on the depth, it can take up to an hour until the OBS resurfaces (e.g. this is a simple calculation: 3000m deep, rising velocity of 1 m/s).

This would be a perfect recovery procedure, but you know, it rarely happens like this! After recovering half of the instruments over the course of about a week, the team got a well-deserved day off on Tristan.

Tristan da Cunha is such a small, beautiful, strange and lonely island. I was almost expecting to find a lost native tribe there, but in truth, it looked like any small town in England, with tiny gardens in front of their houses. Once we arrived at the island we had the choice between taking a touristic tour of the potato fields, where the Tristanians go in summer for holidays, or exploring the island independently.

I decided to go off to the north of the island. It was a perfect day, sunshine with no clouds in the sky, which was surprising for the South Atlantic. I wandered off past the remains of the famous 1961 eruption and the island’s own dumping place until I couldn’t go further. I arrived at a stony beach, from where I could see our ship, the M/S Merian, in the distance, anchored before the island’s coast, since our vessel was too big for Tristan’s small harbour.

I spotted the three penguins standing next to each other sun bathing. ‘Chilled guys’, I thought; and even when I drew closer to take the shot, they looked entirely relaxed and barely noticed me. It’s not like they had seen so many tourists around here! After taking the picture, I placed myself next to them (it’s surprising how smelly they are) to enjoy the view and the sun. Further down the beach, I also spotted a big mama seal and its adorable small fluffy baby. Right in front of me an orca emerged from the waters, properly trying to get to the seals. It flashed its fin before diving down again.

All in all, it was a surreal experience sitting on the remotest island on Earth surrounded by animals I usually only see in a zoo. After one wonderful day on Tristan da Cunha, we went back onboard to continue recovering the remaining OBS from the deep ocean.

By Maria Tsekhmistrenko, University of Oxford (UK)

References

SAMPLE webpage

ISOLDE project description

OBS provided by DEPAS pool in AWI

Imaggeo is the EGU’s online open access geosciences image repository. All geoscientists (and others) can submit their photographs and videos to this repository and, since it is open access, these images can be used for free by scientists for their presentations or publications, by educators and the general public, and some images can even be used freely for commercial purposes. Photographers also retain full rights of use, as Imaggeo images are licensed and distributed by the EGU under a Creative Commons licence. Submit your photos at http://imaggeo.egu.eu/upload/.

Imaggeo on Mondays: Hole in a hole in a hole…

Imaggeo on Mondays: Hole in a hole in a hole…

This photo, captured by drone about 80 metres above the ground, shows a nested sinkhole system in the Dead Sea. Such systems typically take form in karst areas, landscapes where soluble rock, such as limestone, dolomite or gypsum, are sculpted and perforated by dissolution and erosion. Over time, these deteriorating processes can cause the surface to crack and collapse.

The olive-green hued sinkhole, about 20 m in diameter, is made up of a mud material coated by a thin salted cover. When the structures collapse, they can form beautiful blocks and patterns; however, these sinkholes can form quite suddenly, often without any warning, and deal significant damage to roads and buildings. Sinkhole formations have been a growing problem in the region, especially within the last four decades, and scientists are working hard to better understand the phenomenon and the risks it poses to nearby communities and industries.

Some researchers are analysing aerial photos of Dead Sea sinkholes (taken by drones, balloons and satellites, for example) to get a better idea of how these depressions take shape.

“The images help to understand the process of sinkhole formation,” said Djamil Al-Halbouni, a PhD student at the GFZ German Research Centre for Geosciences in Potsdam, Germany and the photographer of this featured image. “Especially the photogrammetric method allows to derive topographic changes and possible early subsidence in this system.” Al-Halbouni was working at the sinkhole area of Ghor Al-Haditha in Jordan when he had the chance to snap this beautiful photo of one of the Dead Sea’s many sinkhole systems.

Recently, Al-Halbouni and his colleagues have employed a different kind of strategy to understand sinkhole formation: taking subsurface snapshots of Dead Sea sinkholes with the help of artificial seismic waves. The method, called shear wave reflection seismic imaging, involves generating seismic waves in sinkhole-prone regions; the waves then make their way through the sediments below. A seismic receiver is positioned to record the velocities of the waves, giving the researchers clues to what materials are present belowground and how they are structured. As one Eos article reporting on the study puts it, the records were essentially an “ultrasound of the buried material.”

The results of their study, recently published in EGU’s open access journal, Solid Earth, give insight into what kind of underground conditions are more likely to give way to sinkhole formation, allowing local communities to better pinpoint sites for future construction, and what spots are best left alone. This study and further work by Al-Halbouni and his colleagues have been published in a special issue organised by EGU journals: “Environmental changes and hazards in the Dead Sea region.”

By Olivia Trani, EGU Communications Officer

Imaggeo is the EGU’s online open access geosciences image repository. All geoscientists (and others) can submit their photographs and videos to this repository and, since it is open access, these images can be used for free by scientists for their presentations or publications, by educators and the general public, and some images can even be used freely for commercial purposes. Photographers also retain full rights of use, as Imaggeo images are licensed and distributed by the EGU under a Creative Commons licence. Submit your photos at http://imaggeo.egu.eu/upload/.

Imaggeo on Mondays: A modern cliff hides ancient dunes

Imaggeo on Mondays: A modern cliff hides ancient dunes

Ancient sand dunes exposed off a cliff face on the shoreline of Nova Scotia at the Islands Provincial Park. The juxtaposition of the high angled strata and flat lying layers above revels the drastic change in climate in Nova Scotia’s history; from vast sand dunes to a calm lake system, and presently the western coastline of the Atlantic Ocean.

Description by Robert Wu, as it first appeared on imaggeo.egu.eu.

Imaggeo is the EGU’s online open access geosciences image repository. All geoscientists (and others) can submit their photographs and videos to this repository and, since it is open access, these images can be used for free by scientists for their presentations or publications, by educators and the general public, and some images can even be used freely for commercial purposes. Photographers also retain full rights of use, as Imaggeo images are licensed and distributed by the EGU under a Creative Commons licence. Submit your photos at http://imaggeo.egu.eu/upload/.