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ESA Top Multimedia

ESA Top Multimedia

Smoke billows from fires in Turkey

Captured by the Copernicus Sentinel-3 mission on 30 July 2021, this image shows smoke billowing from several fires along the southern coast of Turkey.

Mini-tour de la Station Spatiale Internationale avec Thomas Pesquet

ESA astronaut Thomas Pesquet is on his second mission to the International Space Station called Alpha. In this six-minute tour of his home and workplace for six months he describes the changes since his first mission, Proxima, in 2016.

Starting in Europe’s Columbus module, he shows a crew crew quarter installed to accommodate more astronauts living on the Space Station.

Next Thomas is in NASA’s Destiny laboratory, where a new window is available to view Earth. The window itself is not new, but during Proxima it was covered with an experiment for the whole six-month mission, so Thomas could not look out of it.

The third module shown is Japan’s Kibo laboratory. Thomas shows the new glovebox that allows astronauts to run experiments in containment to avoid contamination of the Space Station. This glovebox supplements the European-built Microgravity Science Glovebox that is in NASA’s Destiny lab.

After floating to Node-3 Thomas shows the new toilets that he helped install that will also be used on the lunar Gateway and the water system that recycles up to 95% of all water on the International Space Station.

The tour then shows scenes in Columbus with Thomas and NASA astronaut Megan McArthur floating by on their daily work.

A point-of-view scene passes by NASA astronauts Shane Kimbrough and Mark Vande Hei ending with JAXA astronaut Aki Hoshide looking out of the European-built observatory Cupola – and a return float to end in Columbus with a floating globe.

Over 200 experiments are planned during Thomas’ time in space, with 40 European ones and 12 new experiments led by the French space agency CNES.

Latest updates on the Alpha mission can be found via @esaspaceflight on Twitter, with more details on ESA’s exploration blog via thomaspesquet.esa.int

Background information on the Alpha mission is available at www.esa.int/MissionAlpha with a brochure at www.esa.int/AlphaBrochure


Rover eyes

Rover eyes

BepiColombo Venus flyby

Visualisation of BepiColombo flying by Venus on 10 August 2021. The spacecraft makes nine gravity assist maneouvres (one of Earth, two of Venus and six of Mercury) before entering orbit around the innermost planet of the Solar System.

BepiColombo is an international collaboration between ESA and JAXA.

Solar Orbiter’s second Venus flyby

Visualisation of ESA’s Solar Orbiter spacecraft flying by Venus on 9 August 2021.The spacecraft will make numerous gravity assist flybys at Venus to bring it closer to the Sun and to tilt its orbit in order to observe our star from different perspectives.

Solar Orbiter’s path around the Sun has been chosen to be ‘in resonance’ with Venus, which means that it will return to the planet’s vicinity every few orbits and can again use the planet’s gravity to alter or tilt its orbit. Initially Solar Orbiter will be confined to the same plane as the planets, but each encounter of Venus will increase its orbital inclination. By 2025 it will make its first solar pass at 17º inclination, increasing to 33º by the end of the decade, bringing even more of the polar regions into direct view. This will result in the spacecraft being able to take the first ever images of the Sun’s polar regions, crucial for understanding how the Sun ‘works’, for investigating the Sun-Earth connection and how we can better predict periods of stormy space weather.

Solar Orbiter is an international collaboration between ESA and NASA.

Banjo time!

French Un aspect du travail qui fait peut-être moins rêver : la maintenance. La Station c’est un très *très* gros vaisseau, donc il y a toujours de quoi faire pour entretenir, réparer, améliorer ou remettre en état. Sur cette vidéo censée illustrer la phrase précédente, on dirait que Mark fait tout le boulot au son de mon banjo (en fait, un filtre), mais ne faites pas confiance à vos premières impressions : j’étais concentré en train de le guider à partir des procédures sur ma tablette.

English 100 days in space for #MissionAlpha. It feels like a long time ago, but we also installed new toilets shortly after arriving. I was looking at the procedures on the tablet velcroed to my thigh, and yes, this filter looked so much like a banjo, I had to. The same video specialist at ESA who edits the timelapse videos (and much, much more!), Melanie Cowan, spotted this clip from the Space Station onboard camera views, added some music and the result is… perfectly embarrassing! . True story: I actually helped Mark on this day. A little. Maybe. No one knows.

Beirut in big

Beirut in big

Eutelsat Quantum liftoff

The first flight of Ariane 5 in 2021 delivers two satellites including the ESA-backed telecommunications satellite Eutelsat Quantum into space.

Ariane 5 liftoff

Ariane 5 flight VA254 lifted off with Star One D2 and Eutelsat Quantum from Europe’s Spaceport

Eutelsat Quantum: interview with Silvia Fedi

Discover more about the Eutelsat Quantum telecommunications satellite – and learn what it is like to work at ESA – in an interview with Silvia Fedi, ESA project engineer for the satellite.

Eutelsat Quantum: interview with Shawn Locke

Learn what makes the Eutelsat Quantum telecommunications satellite unique, in an interview with Shawn Locke, ESA project engineer for the satellite.

Ariane 5 on the launch pad

Ariane 5 is poised for liftoff on flight VA254 at Europe’s Spaceport in French Guiana

Pirs undocking

Pirs undocking

Squabbling galactic siblings

A dramatic triplet of galaxies takes centre stage in this latest Picture of the Week from the NASA/ESA Hubble Space Telescope, which captures a three-way gravitational tug-of-war between interacting galaxies. This system —known as Arp 195— is featured in the Atlas of Peculiar Galaxies, a list which showcases some of the weirder and more wonderful galaxies in the universe.

Observing time with the Hubble Space Telescope is extremely valuable, so astronomers don't want to waste a second. The schedule for Hubble observations is calculated using a computer algorithm which allows the spacecraft to occasionally gather bonus snapshots of data between longer observations. This image of the clashing triplet of galaxies in Arp 195 is one such snapshot. Extra observations such as these do more than provide spectacular images — they also help to identify promising targets to follow up with telescopes such as the upcoming NASA/ESA/CSA James Webb Space Telescope.

Earth from Space: Malé, the Maldives

Malé – the capital and most populous city in the Republic of Maldives – is featured in this week's edition of the Earth from Space programme.

Click here to download the Copernicus Sentinel-2 image of Malé, the Maldives.

The orbits of the Galilean moons

The four large moons of Jupiter – Io, Europa, Ganymede and Callisto – are collectively known as the Galilean moons after Galileo Galilei first discovered them in 1609/10, and recognized that they were orbiting Jupiter.

This animation illustrates the relationship of the moons’ orbits with each other. When Ganymede makes one orbit around Jupiter, Europa makes two and Io four. This ‘resonance’ is in the ratio of 1:2:4. Callisto orbits further away and is not in resonance, although may well have been in the past.

ESA’s Jupiter Icy Moons Explorer, Juice, will provide measurements to determine the positions of the Galilean moons with unprecedented accuracy. This will give insight into energy exchanges between the giant planet and its natural satellites, and between the satellites themselves, providing information on the past evolution of the orbits and even the origin and formation of Jupiter and the moons themselves. Important information can also be gleaned on the moon’s interior and activity, and therefore on the consequences for potential habitability. This knowledge can also be applied to exoplanet systems.

Jupiter’s magnetic environment

Simplified view of the magnetic environment around Jupiter and its four largest moons: Io, Europa, Ganymede and Callisto. In reality the interactions are extremely variable and complex. ESA’s Jupiter Icy Moons Explorer, Juice, will investigate the magnetic environment in great detail, exploring the invisible connections between the moons and the giant planet to understand more about the interplay of this intensively dynamic system.

The animation begins with a short focus on Jupiter. The giant planet’s aurorae are displayed as a blue ring around the north and south polar regions, and its magnetic field lines are shown in dark purple throughout. The animation then moves through the key elements of the magnetic field situation at each of the moons.

Callisto, the outermost of the four large moons, is the first to be seen, showing the geometry of the magnetic field created within the moon’s putative subsurface ocean as the moon moves through Jupiter’s magnetic field.

The next sequence shows the Ganymede’s magnetic environment, which is a combination of an induced and internal magnetic field. Ganymede is unique in the Solar System in that it is the only moon known to generate its own magnetic field, which has complex interactions with Jupiter’s own vast magnetic field. Ganymede’s auroral ovals are illustrated in blue rings in the mid northern and southern latitudes; they are influenced by Jupiter’s magnetic field as well as the moon’s buried ocean.

Europa is represented next, with its magnetic field created within its subsurface ocean.

Io, the innermost of the four large moons, is illustrated with vertical magnetic field lines connecting to Jupiter. Io is a volcanic moon, and its thin sulphur dioxide atmosphere generates an ionized plasma torus around Jupiter, seen as the hazy yellow ring.

Zooming out, the final sequence shows Jupiter and its large moons, as well as the Io torus, created by the ionization of the volcanic moons’ atmosphere.

Jupiter and its four large moons are often considered as an archetype for a solar system in their own right. Thus Juice’s investigations of the moons and their interactions with Jupiter will provide unique insight into the numerous exoplanet systems that have been discovered elsewhere in the Universe.

Inside the Galilean moons

This animation shows the interior structure of the four Galilean moons of Jupiter: Io, Europa, Ganymede and Callisto. While Io is an active volcanic world with a magma ocean below its crust, the other moons are icy, and are thought to host subsurface liquid oceans that will be explored in detail by ESA’s Jupiter Icy Moons Explorer.

Europa has a dynamic icy crust overlying what is thought to be a liquid water ocean. It also has a rocky mantle and solid core. Juice will search for liquid water below the most active sites observed on the surface. The spacecraft will study material exchange between the interior and the surface, as well as measure the moon’s gravity field to better define its structure and layers.

Ganymede has an icy crust with evidence of a subsurface liquid ocean overlying an icy mantle, a rocky mantle, and core. Juice will characterise the icy crust and the extent of the subsurface ocean. It will also measure Ganymede’s intrinsic magnetic field in great detail. It is the only moon in the Solar System to generate its own magnetic field, which has complex interactions with Jupiter’s own vast magnetic field, and Juice will study the relationship between the two.

Callisto has an icy crust and is suspected to have a subsurface liquid ocean with its internal core likely a mix of ice and rocks. Here Juice’s focus will be the understanding of the interior structure and the detection of the putative subsurface ocean.

Understanding the state of the moons’ interiors, and in particular if they host liquid water, will help answer important questions about the habitability potential of these moons, and of similar exoplanet systems elsewhere in our Universe.

Juice takes the heat

ESA's Jupiter Icy moons Explorer, Juice, has successfully completed rigorous thermal tests simulating the extreme coldness of space and the warmth of the Sun at ESA’s test centre ESTEC, in The Netherlands.

The spacecraft underwent a month of round-the-clock testing and monitoring in the Large Space Simulator, which recreates the vacuum of space and is able to simulate both hot and cold space environments. The spacecraft was subjected to temperatures ranging from 250 degrees to minus 180 degrees Celsius, showing that it can survive its journey in space.

Juice will launch in 2022 to our Solar System’s largest planet. It will spend over four years studying Jupiter’s atmosphere, magnetosphere and its icy moons Europa, Callisto and Ganymede, investigating whether the moons’ subsurface oceans are habitable for life.

This film contains interviews with Pauline Ravily – Airbus Thermal Architect, Eduardo Bernar - European Test Services, ESA, and ESA's Juice Project Scientist, Olivier Witasse.

Jupiter mission passes space vacuum test

Jupiter mission passes space vacuum test

Baja bedtime timelapse

Timelapse video made during ESA astronaut Thomas Pesquet’s second mission to the International Space Station, “Alpha”. The camera is setup to take pictures at intervals of two a second, and the pictures are then edited into this video that plays at 25 pictures a second. The video is around 12 times faster than real speed.

Thomas shared this video on social media with the caption:

“Before going to sleep, let’s ride around Earth on Timelapse Tuesday, I like how the shadows dance up and down the Canadarm on this one.”

The timelapse starts with the International Space Station flying over Baja, California, and continuing down the western coast of South America.

Over 200 experiments are planned during Thomas’ time in space, with 40 European ones and 12 new experiments led by the French space agency CNES.

Latest updates on the Alpha mission can be found via @esaspaceflight on Twitter, with more details on ESA’s exploration blog via thomaspesquet.esa.int.

Background information on the Alpha mission is available at www.esa.int/MissionAlpha with a brochure at www.esa.int/AlphaBrochure.              

Hubble finds first evidence of water vapour at Jupiter’s moon Ganymede

Astronomers have used archival datasets from the NASA/ESA Hubble Space Telescope to reveal the first evidence for water vapour in the atmosphere of Jupiter’s moon Ganymede, the result of the thermal escape of water vapour from the moon’s icy surface.

Jupiter’s moon Ganymede is the largest moon — and the ninth-largest object — in the Solar System. It may hold more water than all of Earth's oceans, but temperatures there are so cold that water on the surface freezes and the ocean lies roughly 160 kilometres below the crust. Nevertheless, where there is water there could be life as we know it. Identifying liquid water on other worlds is crucial in the search for habitable planets beyond Earth. And now, for the first time, evidence has been found for a sublimated water atmosphere on the icy moon Ganymede.

In 1998,  Hubble’s Space Telescope Imaging Spectrograph (STIS) took the first ultraviolet (UV) pictures of Ganymede, which revealed a particular pattern in the observed emissions from the moon’s atmosphere. The moon displays auroral bands that are somewhat similar to the auroral ovals observed on Earth and other planets with magnetic fields. These images were therefore illustrative evidence that Ganymede has a permanent magnetic field. The similarities between the two ultraviolet observations were explained by the presence of molecular oxygen, O2. The differences were explained at the time by the presence of atomic oxygen, O, which produces a signal that affects one UV colour more than the other. 

As part of a large observing programme to support NASA’s Juno mission in 2018, Lorenz Roth, of the KTH Royal Institute of Technology in Stockholm, Sweden, led a team that set out to capture UV spectra of Ganymede with Hubble’s Cosmic Origins Spectrograph (COS) instrument to measure the amount of atomic oxygen. They carried out a  combined analysis of new spectra taken in 2018 with the COS and archival images from the STIS instrument from 1998 and 2010. To their surprise, and in contrast to the original interpretations of the data from 1998, they discovered there was hardly any atomic oxygen in Ganymede's atmosphere. This means there must be another explanation for the apparent differences between the UV aurora images.

The explanation was then uncovered by Roth and his team in the relative distribution of the aurorae in the two images. Ganymede's surface temperature varies strongly throughout the day, and around noon near the equator it may become sufficiently warm that the icy surface releases some small amounts of water molecules. In fact, the perceived differences between the UV images are directly correlated with where water would be expected in the moon’s atmosphere. 

Initially only the O2 had been observed,” explained Roth. “This is produced when charged particles erode the ice surface. The water vapour that we have now measured originates from ice sublimation caused by the thermal escape of H2O vapour from warm icy regions.

This finding adds anticipation to ESA’s upcoming JUpiter ICy moons Explorer (Juice) mission — the first large-class mission in ESA's Cosmic Vision 2015–2025 programme. Planned for launch in 2022 and arrival at Jupiter in 2029, it will spend at least three years making detailed observations of Jupiter and three of its largest moons, with particular emphasis on Ganymede as a planetary body and potential habitable world. Ganymede was identified for detailed investigation because it provides a natural laboratory for the analysis of the nature, evolution and potential habitability of icy worlds in general and the role it plays within the system of Galilean satellites, and its unique magnetic and plasma interactions with Jupiter and its environment (known as the Jovian system).

Our results can provide the Juice instrument teams with valuable information that may be used to refine their observation plans to optimise the use of the spacecraft,” added Roth. 

Understanding the Jovian system and unravelling its history, from its origin to the possible emergence of habitable environments, will provide us with a better understanding of how gas giant planets and their satellites form and evolve. In addition, new insights will hopefully be found into the potential for the emergence of life in Jupiter-like exoplanetary systems.

We are going

We are going

Eutelsat Quantum is mated to its launcher

Eutelsat Quantum is mated to its launcher

Duneside view of ESA's technical heart

Duneside view of ESA's technical heart

Counting carbon

The Paris Agreement adopted a target for global warming not to exceed 1.5°C. This sets a limit on the additional carbon we can add to the atmosphere – the carbon budget. Only around 17% of the carbon budget is now left. That is about 10 years at current emission rates.

Each country reports its annual greenhouse gas emissions to the United Nations. Scientists then set these emissions against estimates of the carbon absorbed by Earth’s natural carbon sinks. This is known as the bottom-up approach to calculating the carbon budget.

Another way to track carbon sources and sinks is to measure the amounts of greenhouse gases in the atmosphere from space – the top-down approach. As well as tracking atmospheric carbon, ESA’s Climate Change Initiative is using satellite observations to track other carbon stocks on land and sea.

How we use the land accounts for about a quarter of our greenhouse gas emissions. Forests are the largest store of carbon on the land. Fire acts as a conduit for carbon to pass from the land to the atmosphere. And phytoplankton in the ocean are an important carbon sink.

ESA’s Regional Carbon Cycle Analysis and Processes project is using this information to reconcile the differences between the bottom-up and top-down approaches. Observations are combined with atmospheric and biophysical computer models to deduce carbon fluxes at the surface. This will improve the precision of each greenhouse gas budget and help separate natural fluxes from agricultural and fossil fuel emissions. This work will help us gauge whether we can stay within the 1.5°C carbon budget, or if more warming is in store.

Earth from Space: Tarso Toussidé

This week’s edition of the Earth from Space programme features a false-colour composite image of the Tarso Toussidé volcanic massif, captured by the Copernicus Sentinel-2 mission.

See also Tarso Toussidé, Chad to download the image.

Tarso Toussidé, Chad

The Tarso Toussidé volcanic massif is featured in this false-colour composite image captured by the Copernicus Sentinel-2 mission.

Cosmic lens flare

The centre of this image from the NASA/ESA Hubble Space Telescope is framed by the tell-tale arcs that result from strong gravitational lensing, a striking astronomical phenomenon which can warp, magnify, or even duplicate the appearance of distant galaxies. 

Gravitational lensing occurs when light from a distant galaxy is subtly distorted by the gravitational pull of an intervening astronomical object. In this case, the relatively nearby galaxy cluster MACSJ0138.0-2155 has lensed a significantly more distant quiescent galaxy — a slumbering giant known as MRG-M0138 which has run out of the gas required to form new stars and is located 10 billion light years away. Astronomers can use gravitational lensing as a natural magnifying glass, allowing them to inspect objects like distant quiescent galaxies which would usually be too difficult for even Hubble to resolve.

This image was made using observations from eight different infrared filters spread across two of Hubble’s most advanced astronomical instruments: the Advanced Camera for Surveys and the Wide Field Camera 3. These instruments were installed by astronauts during the final two servicing missions to Hubble, and provide astronomers with superbly detailed observations across a large area of sky and a wide range of wavelengths.

ESA Telecom Partnership Projects

ESA Partnership Projects federate industry around large-scale programmes, developing innovative cutting-edge solutions in partnership with private or public operators. This innovative approach allows European prime contractors and equipment suppliers to be competitive in the market. ESA Partnership Projects generate great benefits for industry and member states.