Sentinel-3B being mated with the Rockot adapter

Sentinel-3B being removed from the fuelling stand to be installed on its flight adapter.
The Copernicus Sentinel-3B satellite is being prepared for liftoff, scheduled for 25 April 2018. Its identical twin, Sentinel-3A, has been in orbit since February 2016. The two-satellite constellation offers optimum global coverage and data delivery for Europe’s Copernicus environment programme.

Click here to visit Original posting

Fairing inspection

The Rockot fairing being inspected for cleanliness in preparation for the installation of Sentinel-3B.

The satellite is being prepared for liftoff, scheduled for 25 April 2018. Its identical twin, Sentinel-3A, has been in orbit since February 2016. The two-satellite constellation offers optimum global coverage and data delivery for Europe’s Copernicus environment programme.

Click here to visit Original posting

Horizons News Conference

ESA astronaut Alexander Gerst's last news conference in Europe before his second launch into space. The event was presented in German and English.

The mission is called Horizons to evoke exploring our Universe, looking further than our planet and broadening our knowledge.
Alex will be launched in June with US astronaut Serena Auñón-Chancellor and Russian cosmonaut Sergei Prokopyev from the Baikonur cosmodrome, Kazakhstan, in the Soyuz MS-09 spacecraft.

Click here to visit Original posting

Moondive

It’s one of the deepest ‘swimming pools’ in Europe, but for three years has been helping preparations for a human return to the Moon. ESA’s Neutral Buoyancy Facility at the European Astronaut Centre has been the site of the ‘Moondive’ study, using specially weighted spacesuits to simulate lunar gravity, which is just one sixth that of Earth.

The three-year study took place in the Centre’s 10-m deep Neutral Buoyancy Facility (NBF) near Cologne in Germany. This is one of four such immersion tanks worldwide – the others are in the United States, China and Russia – and is used to train astronauts for ‘extra vehicular activity’ (EVA), also known as spacewalks.

With International Space Station operations moving towards an international lunar return in the late 2020s, ESA’s NBF has been used to investigate moonwalk procedures for the lunar surface.

Moondive was run by a consortium led by the French company, COMEX, which specialises in human and robotic exploration of extreme environments.

Click here to visit Original posting

Radar echoes

Searching for signs of ice on Mars is complex. To explore whether ice lurks beneath the surface of the Red Planet, ESA’s Mars Express uses its radar to probe the interior.

It sends low-frequency radio pulses at Mars and records how they are returned to the spacecraft. These pulses can penetrate some of the material comprising the planet’s crust, bouncing back to Mars Express when they reach a layer of a different density or composition. By analysing the time delays of these returned pulses, scientists can determine the properties of material lying beneath the surface.

This image shows radar echoes from Meridiani Planum, an area near Mars’ equator that is also being explored by NASA’s Opportunity rover.

In the image, reflected echoes from the surface and subsurface, separated in time delay, are plotted along the ground track of the spacecraft’s orbit. The bright white line crossing the frame marks the surface of Mars, while the faint, more diffuse line just below represents echoes from the base of a layer of buried material located far below the surface.

The surface of Meridiani Planum is full of volcanic sands that are known to contain minerals that formed in the presence of water in the planet’s distant past. Previously, it was unclear what kinds of materials lay beneath the surface here, but the Mars Express radar has now penetrated the deposits and revealed that they have a similar property to ice.

However, a recent study instead suggests an ice-free explanation, showing that these radar properties could just as easily be explained by a thick layer of porous sand – perhaps blown into the region by winds. Unlike other geologic materials, such as volcanic ash or very fine dust, a thick layer of sand-sized particles may produce properties in the radar akin to that of an ice-rich deposit.

The echoes are thought to be reflections from the boundary between Meridiani Planum deposits below the surface, and cratered terrain lying deeper still.

These results highlight the difficulty in finding buried ice, and will help scientists to identify areas with and without accessible water ice: a resource critical to the future human exploration and possible colonisation of Mars.

This radargram was obtained by the Mars Advanced Radar for Subsurface and Ionosphere Sounding instrument, MARSIS, in April 2016. The image covers a width of about 80 km. North is to the left (see annotated version in the published paper for more details). 

Click here to visit Original posting

Fuelling Sentinel-3B

The team of propulsion experts has spent two days carrying out the tricky task of fuelling the Copernicus Sentinel-3B satellite with 130 kg of hydrazine and pressurising the tank for its life in orbit.

Since hydrazine is extremely toxic, only specialists remained in the cleanroom for the duration. A doctor and security staff waited nearby with an ambulance and fire engine ready to respond to any problems.

The satellite is scheduled for liftoff on 25 April from Russia’s Plesetsk Cosmodrome at 17:57 GMT (19:57 CEST).

Click here to visit Original posting

Hyderabad, India

The Copernicus Sentinel-2A satellite takes us over southern India to the capital of Telangana: Hyderabad.

Home to almost seven million people and covering about 650 sq km, Hyderabad is one of the largest metropolitan areas in India. It lies on the banks of the Musi River, which can be seen running across the middle of the image. Although steeped in history, this rapidly growing metropolis has become a hub of commerce and an international centre for information technology, earning it the nickname of Cyberabad.

Captured on 14 May 2017, the image has been processed to highlight the different features in and around the city. The yellow and browns show the built-up centre while the light greens in the surroundings show arid fields. The shades of darker green depict vegetation and areas covered by trees. Interestingly, the bright blue, which appears, for example, along the Musi River and near other water bodies, is also vegetation such as parkland and grass.

While several lakes can be seen in the image, they are gradually being lost. It has been said that the city once had 7000 lakes, but there are now only about 70 and they are being subjected to pollution as the city expands and develops. Even the city’s most famous lake, the heart-shaped Hussain Sagar, is blighted with pollution from agricultural and industrial waste and municipal sewage.

The two identical Copernicus Sentinel-2 satellites carry high-resolution cameras working in 13 spectral bands. Images from the mission can be used to monitor pollution in lakes, changes in vegetation and urban growth.

This image is featured on the Earth from Space video programme.

Click here to visit Original posting

Magnetic lithosphere detailed

This is the most detailed map ever of the tiny magnetic signals generated by Earth’s lithosphere. The map, which is being used to understand more about Earth’s geological history, is thanks to four years’ of measurements from ESA’s trio of Swarm satellites, historical data from the German CHAMP satellite and observations from ships and aircraft.

Erwan Thebault from the University of Nantes in France said, “This is the highest resolution model of the lithospheric magnetic field ever produced.

"With a scale of 250 km, we can see structures in the crust like never before. And, we have gained even finer detail in some parts of the crust, such as beneath Australia, where measurements from aircraft have mapped at resolution of 50 km.

“This combined use of satellite and near-surface measurements gives us a new understanding of the crust beneath our feet, and will be of enormous value to science.”

Most of Earth’s magnetic field is generated deep within the outer core by an ocean of superheated, swirling liquid iron, but there are also much weaker sources of magnetism. The Swarm constellation has been used to yield some discoveries about these more elusive signals, such as that from Earth’s lithosphere. A small fraction of the magnetic field comes from magnetised rocks in the upper lithosphere, which includes Earth’s rigid crust and upper mantle. This lithospheric magnetic field is very weak and therefore difficult to detect from space. As new oceanic crust is created through volcanic activity, iron-rich minerals in the upwelling magma are oriented to magnetic north at the time and solidified as the magma cools. Since magnetic poles flip back and forth over time, the solidified magma due to mantle upwelling at mid-oceanic ridges forms magnetic ‘stripes’ on the seafloor which provide a record of Earth’s magnetic history. These magnetic imprints on the ocean floor can be used as a sort of time machine, allowing past field changes to be reconstructed and showing the movement of tectonic plates from hundreds of million years ago until the present day.

Click here to visit Original posting