Earth from space: image of the week

[jacqmans]

Earth from Space: Giza, Egypt
18/04/2025

This very high-resolution image captures the Egyptian city of Giza and its surrounding area, including the world-famous Giza Pyramid Complex.

The third largest city in Egypt by area, Giza is on the west bank of the Nile River, which flows north on the right of the image, separating Giza on the west from the capital Cairo to the east. A number of bridges can be seen connecting the two cities.

Known as the father of African rivers, the Nile is the longest river in the world. The fertile land near its banks has always allowed the Egyptians to grow produce and thrive in the arid desert.

In this image, the green agricultural fields stand out against the grey of Giza’s dense conurbation. To the southwestern edge of the city, yellow and ochre denote the dry sand of the desert and the Giza Plateau, hosting some of the most impressive ancient monuments in the world.

The distinctive shape of the Great Pyramids of Giza can be observed in the lower part of the image, half lit by the Sun and casting distinctive shadows. The northernmost and largest pyramid seen here is that of Khufu, or Cheops, and is also the oldest of the three, built in around 2600 BC. The middle pyramid was built for the pharaoh Khafre and the southernmost and smallest of the three monuments is that of Menkaure, built in around 2510 BC.

Zooming in, smaller pyramids can be seen adjacent to the Cheops and the Menkaure pyramids. These were burial sites for other members of the royal family. The square structures of mortuary temples are also visible near each pyramid. East of the Khafre pyramid, the Great Sphinx can be recognised, one of Egypt’s most famous landmarks.

About 2 km northwest of the pyramids lies the Grand Egyptian Museum, visible as a white, rhomboid structure surrounded by large plazas filled with date palms. Occupying a 50-hectare plot of land, the museum is the largest archaeological museum in the world.

This image was acquired by the Vision-1 mission, which provides images with a resolution of up to 0.87 m. Vision-1 is part of ESA’s Third Party Missions programme, which means ESA uses its multi-mission ground systems and expertise to acquire, process, distribute and archive data from a wide range of satellite missions developed and operated by other agencies.

[jacqmans]

Earth from Space: French Guiana
25/04/2025

Copernicus Sentinel-1 captured this radar image over French Guiana – home to Europe’s Spaceport in Kourou, where ESA’s Biomass mission is being prepared for liftoff on 29 April onboard a Vega-C rocket.

This false-colour view shows part of the northeast coast of South America, stretching from the estuary of the Kourou River in French Guiana in the east, to Suriname, west of the Maroni River. The latter is visible as a dark line, snaking its way across the image and marking the border between the two countries.

The colours in this image come from the combination of two polarisations from the Copernicus Sentinel-1 mission, which have been assigned a colour and converted into a single composite. This processing technique helps to distinguish different types of surface, thereby providing detailed information.

Here, water is clearly reflected in dark shades of blue. Distinct wave patterns can be seen in the Atlantic Ocean since the radar signal is highly sensitive to changes in the roughness on the water: calm waters appear darker, while rough seas appear brighter.

The dark, branching waterways of the Petit Saut Reservoir stand out in the centre-right of the image. The water body was formed by a hydroelectric dam built on the Sinnamary River. The river can be seen winding its way north to eventually drain into the Atlantic Ocean.

Most of the land is shown in vibrant shades of yellow, indicating tropical rainforests and other areas of vegetation, where radar signal interacts and bounces from the complex structure of the canopy, including tree trunks, branches and leaves. Built-up areas appear more colourful than the surroundings.

With over 90% of land covered by forest, French Guiana is the territory with the most trees per inhabitant in the world. Since it is an overseas department of France, it is also the only part of the Amazonian forest in the EU.

Northeast of the Petit Saut Reservoir, on the coast between the estuary of the Sinnamary River and the Kourou River, lies Europe's Spaceport. This is home to the ESA-developed Ariane and Vega rocket families and allows for independent, reliable access to space for Europe.

From here, ESA’s Biomass mission is scheduled to launch on a Vega-C rocket on 29 April.

Once in orbit, this latest Earth Explorer mission will provide vital insights into the health and dynamics of the world’s forests, revealing how they are changing over time and, critically, enhancing our understanding of their role in the global carbon cycle, and hence in the climate system.

[jacqmans]

Earth from Space: World’s biggest iceberg
02/05/2025

The Ocean and Land Colour Instrument on Copernicus Sentinel-3 captured this image of Earth’s biggest iceberg, A23a, on 5 April 2025.

The ice mass is currently lodged on the seabed 73 km from the remote island of South Georgia, which can be seen just poking out from beneath the cloud cover.

Although the size of the island is not clearly visible in this image, it is only marginally bigger than the iceberg. The A23a is estimated to cover an area of 3460 sq km – twice the size of Greater London in the UK. In comparison, the island of South Georgia is 3528 sq km.

An image of the berg was also featured by ESA in December 2023 when it was dislodged from the ocean floor and was pushed by currents away from the Antarctic. It initially calved from Filchner Ice Shelf in 1986. Since then, it has travelled more than 2000 km.

A23a has started to disintegrate and many smaller blocks of ice are visible in the dark blue ocean, particularly to the north of the berg. The disintegration is typical of icebergs that reach this far north and is caused by the warmer sea temperatures and weather conditions.

South Georgia is a mountainous island 170 km in length, with a central ridge that reaches a height of 2935 m. It lies in the South Atlantic Ocean, about 1400 km east of the Falkland Islands (Las Malvinas) and northeast of the tip of the Antarctic Peninsula.

It is the largest of the South Georgia and South Sandwich archipelago, a British overseas territory and is home to a range of biodiversity, including penguins and seals, as well a British Antarctic Survey research station.

[jacqmans]

Earth from Space: Northwest Sardinia, Italy
09/05/2025

Part of the Italian island of Sardinia is featured in this image captured by the Copernicus Sentinel-2 mission.

With an area of about 24 090 sq km, Sardinia is the second-largest island in the Mediterranean Sea, after Sicily. It is situated about 200 km west of the Italian peninsula, a similar distance north of Tunisia, and is separated from the French island of Corsica by just 12 km.

The area pictured here covers a section of the province of Sassari in the northwestern part of the island, with the Sardinian Sea to the west and the Gulf of Asinara to the north.

The urban agglomeration of the city of Sassari can be seen as a brown and grey area near the centre of the image, about 10 km inland from the northern coast. Sassari lies at about 225 m above sea level on a wide plateau that slopes down towards the Gulf of Asinara. The city is surrounded by a green belt of agricultural fields and olive plantations.

The seaport serving Sassari is Porto Torres, lying on the coast along the Gulf of Asinara. The gulf is named after Asinara Island, visible at the northwest tip of the gulf. Once home to one of Italy’s top-security prisons, Asinara Island is now a protected marine and wildlife reserve.

Zooming in, it's interesting to note how the waters within the gulf appear calm compared to the rough waters of the open sea to the west, where distinct wave patterns can be clearly identified. The white colour all along the western coastline is caused by the big waves crashing against the rocky cliffs.

Moving south, two bays are visible at the bottom of the image: the smaller bay of Porto Conte and the larger bay of Alghero. Here, the city of Alghero extends along the coast, while the port of Fertilia lies  at the northern end of the bay. The runways of the Alghero-Fertilia Airport can be spotted just inland from Fertilia.

In the area between Alghero, Sassari and Porto Torres lies the plain of Nurra. Covering a surface of about 700 sq km, Nurra is the second-largest plain on the island, dominated in the image by agricultural fields, with a large section devoted to vineyards.

[jacqmans]

Earth from Space: Svalbard Archipelago
16/05/2025

The Copernicus Sentinel-2 mission brings us this cloud-free view of Svalbard, a remote Norwegian archipelago in the Arctic Ocean.

Located north of mainland Europe, Svalbard is roughly halfway between Norway and the North Pole. It is surrounded by four bodies of water: the Arctic Ocean, the Greenland Sea to its west, the Barents Sea to the east and the Norwegian Sea to the south.

The archipelago is dominated by rugged mountains, deeply indented fjords and numerous glaciers. The colourful shades of green in the waters along the coasts are likely due to sediment discharges, eroded by the flow of ice and then carried by meltwater into the sea.

Nine main islands make up the archipelago, which covers a total area of around 62 700 sq km. The largest is Spitsbergen, visible here in the left of the image, followed by Nordaustlandet to its top right, mainly covered by large ice caps, Edgeøya at the bottom right, and Barentsøya, north of Edgeøya.

Spitsbergen, which is around the same size as Switzerland, has a mountainous landscape, with elongated valleys and a jagged western coastline, shaped by glacial erosion and marine incursion. Its highest point is Mount Newton, around 1717 m, in the northeast.

Opening on Spitsbergen's north coast is Wijdefjorden, the longest fjord of the archipelago. It runs 108 km southwards, separating Andrée Land in the west from Margaretas Land in the east.

Spitsbergen is the only permanently populated island of the archipelago and Longyearbyen is the largest settlement. Near Longyearbyen sits the Svalbard Satellite Station – SvalSat for short. Its position enables it to track all 14 daily passes of polar-orbiting satellites. It has worked with a range of Earth observation missions including Aeolus, Swarm, CryoSat and Copernicus Sentinel-1, Sentinel-2 and Sentinel-3.

This image was generated using multiple scans captured by Copernicus Sentinel-2 between June and September 2024. By choosing the cloud-free pixels over a long period of time, such clear, high-resolution mosaics can be created, which are especially valuable to overcome the persistent challenges of limited visibility, due to cloud cover and polar night, in the Svalbard area.

These multitemporal composites optimise land cover classification, glacier boundary delineation and vegetation mapping in the short Arctic summer. Additionally, the frequent revisit time of Sentinel-2 – up to every five days at mid-latitudes – allows researchers to build detailed annual or seasonal composites, enabling consistent monitoring of environmental changes across the archipelago.