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ESA Top Multimedia

ESA Top Multimedia

Lunch with the Moon

For the first time in more than three years, on 26 May 2021, a total lunar eclipse coincided with a supermoon. The 'super blood moon' was unfortunately only visible across Australia and parts of the US and East Asia. But ESA, in cooperation with the Australian science agency, CSIRO, brought this celestial treat to European viewers through its live webcast "Lunch with the Moon". 
Catch the replay of this unique event, which includes live footage of the Moon from across the globe and conversations with experts on the science of lunar eclipses, what would happen if there were no Moon, fascinating insights into Europe's future at the Moon including the Moonlight project, lunar robots and robotics, a future human lunar base and much more. 

In the programme, the moment of “totality” – when the Moon is fully shrouded in Earth’s shadow – begins around 1:46:00. 
02:10 Deep-space communication from Australia 
13:00 All about lunar eclipses 
29:10 What if there were no Moon? 
43:20 Europe goes forward to the Moon 
58:45 Moonlight: Connecting Earth with the Moon 
1:13:20 Humans at work in a lunar setting 
1:28:20 Lunar robots 
1:43:45 Science and future exploration 

Jupiter antenna that came in from the cold

Jupiter antenna that came in from the cold

Lunch with the Moon

ESA astronaut Thomas Pesquet snapped this image of the Moon from the Russian segment on board the International Space Station earlier this month.

Currently on his first month of the six-month Alpha mission, Thomas is taking stunning photos of Earth and other wondrous objects when not working on science or Station maintenance.

“The blueish picture is when it was still low and the sky was not yet dark,” he notes. “It turned into its black and white self only moments later.”

Parts of North and South America, Australia and the Pacific will be treated to a lunar eclipse, which occurs when the Moon is engulfed by Earth’s shadow and the only sunlight that reaches its surface passes through our planet’s atmosphere, giving it a beautiful red-orange tint.

Today’s lunar eclipse will be the only total lunar eclipse of this year, and that same evening the Moon will be just 357 311 km away, often called a ‘SuperMoon’.

Despite the first human visit more than 50 years ago, the Moon remains largely unexplored yet promises to help us understand the formation of our planet, how crucial chemicals like water, necessary for life, came to the Earth-Moon system, and how we could one day use resources on the Moon to enable human presence.

In the near future, ESA will go ‘forward to the Moon’ when the European Service Module powers NASA’s Orion mission into lunar orbit, and in the next decade, ESA will play a key role in the development of the Gateway, an orbiting science station that will support future human landings.

For now, ESA is bringing the lunar eclipse to Europe with real-time coverage of the total lunar eclipse starting at midday today, 26 May, on ESA Web TV.

The live programme begins at 11:30 CEST and runs over lunchtime in Europe and will provide commentary on this fantastic eclipse, with special guest astronomers, scientists, engineers and experts from Europe and Australia.

Watch a replay of the livestream here

For more stunning images from space, follow Thomas Pesquet during Mission Alpha here.

ExoMars parachute extraction tests – Airborne Systems

A series of clips from different angles and at different speeds showing parachute extraction tests for the ExoMars 2022 mission’s first main parachute using a NASA/JPL test rig powered by compressed air. The lid of the parachute assembly is pulled along a suspended cable at high speed while the end of the assembly is fixed to a wall. When the release mechanism is activated, the parachute bag is pulled away from the parachute at the target speed, mimicking the extraction as it will be on Mars. At the highest speeds, the tests enable the extraction to take place at more than 200 km/h.

In this video the first main parachute and bag provided by Airborne Systems is featured. The tests took place in April 2021.
The ESA-Roscosmos ExoMars mission, with the Rosalind Franklin rover and Kazachok surface platform contained in a descent module, requires two main parachutes – each with its own pilot chute for extraction – to help slow it down as it plunges through the martian atmosphere. The 15 m-wide first stage main parachute will open while the descent module is still travelling at supersonic speeds, and the 35 m-wide second stage main parachute is deployed once at subsonic speeds.

A menagerie of galaxies

This packed ESA/Hubble Picture of the Week showcases the galaxy cluster ACO S 295, as well as a jostling crowd of background galaxies and foreground stars. Galaxies of all shapes and sizes populate this image, ranging from stately spirals to fuzzy ellipticals. As well as a range of sizes, this galactic menagerie boasts a range of orientations, with spiral galaxies such as the one at the centre of this image appearing almost face on, and some edge-on spiral galaxies visible only as thin slivers of light.

The cluster dominates the centre of this image, both visually and physically. The huge mass of the galaxy cluster has gravitationally lensed the background galaxies, distorting and smearing their shapes. As well as providing astronomers with a natural magnifying glass with which to study distant galaxies, gravitational lensing has subtly framed the centre of this image, producing a visually striking scene.

Follow your dreams

It was always Andreas Møgensen's dream to become an astronaut, even if he was sometimes hesitant to admit it.

In this video he encourages others to follow their dreams, and send in their application for ESA's astronaut selection.

Arctic sea-ice volume 2010–19

Previous research suggested that sea ice is able to recover in the winter following a strong summer melt because thin ice grows faster than thick ice. However, new findings that heat from the Atlantic Ocean is overpowering this stabilising effect – reducing the volume of sea ice that can regrow in the winter. This means that sea ice is more vulnerable during warmer summers and winter storms. The new research, published recently in the Journal of Climate, describes how scientists used satellite data including that from CryoSat and SMOS through ESA’s Climate Change Initiative to calculate changes in the volume of Arctic sea ice between 2002 and 2019.

Read full story: Arctic sea ice succumbs to Atlantification

Earth from Space: Los Cabos, Mexico

In this week's edition of the Earth from Space programme, the Copernicus Sentinel-2 mission takes us over Los Cabos – a municipality on the southern tip of Mexico's Baja California Peninsula.

See also Los Cabos, Mexico to download the image.

Los Cabos, Mexico

A Copernicus Sentinel-2 image of Los Cabos – a municipality on the southern tip of Mexico's Baja California Peninsula.

Cool test of Proba-V companion

Cool test of Proba-V companion

A matter of time

10 years of AMS-02 on the International Space Station

Meet the world’s largest iceberg

An enormous iceberg has calved from the western side of the Ronne Ice Shelf, in the Weddell Sea, in Antarctica. The iceberg, dubbed A-76, measures around 4320 sq km in size and is currently the largest berg in the world.

Getting ready to rocket

The pieces are stacking up for the launch of Artemis 1 mission around the Moon and back. The massive Space Launch Systems (SLS) rocket that will launch the first crewless test flight of the Orion spacecraft, powered by the European Service Module, is being integrated at the Vehicle Assemble Building at NASA’s Kennedy Space Center in Florida, USA.

Visible in this image are the twin solid fuel rocket boosters, now fully stacked atop the mobile launcher. The boosters will be mated with the rocket’s 65 m tall core stage that recently barged in to Florida aboard the Pegasus barge on 27 April after successful testing at NASA’s Stennis Space Center in Mississippi. 

Once the rocket stages are ready to go, the Orion spacecraft and additional flight hardware are next up for integration.

Since our last Orion and the European Service Module update for Artemis I, the spacecraft has moved, from the NASA Kennedy Space Center’s Neil Armstrong Operations and Checkout facility, a few kilometres down the road to the Multi Payload Processing Facility. The names of these buildings give the game away. The first Orion spacecraft has been checked out and is ready for the next step on the road to space: processing for launch.

Fuelling was completed on 1 April, after which the system will be serviced in high pressure helium that serves as a pressurisation agent to the European Service Module propellant tanks, ensuring the correct pressure at the engine inlets.

Eventually, the spacecraft will be hoisted to the top of the fully stacked SLS rocket.

Read more updates on the Orion blog

The European Service Module is ESA’s contribution to NASA’s Orion spacecraft that will send astronauts, including the first European, to the Moon and beyond. Follow Europe’s role in the mission here.

Cosmic silver lining

This Picture of the Week showcases the emission nebula NGC 2313. The bright star V565 — surrounded by four prominent diffraction spikes — illuminates a silvery, fan-shaped veil of gas and dust, while the right half of this image is obscured by a dense cloud of dust. Nebulae with similar shapes — a star accompanied by a bright fan of gas — were once referred to as cometary nebulae, though the name is no longer used. 

The language that astronomers use changes as we become better acquainted with the Universe, and astronomical history is littered with now-obsolete phrases to describe objects in the night sky, such as “spiral nebulae” for spiral galaxies or “inferior planets” for Mercury and Venus. 

While modern astronomical terminology has become steadily more precise, the nature of objects in astronomical exposures can still occasionally puzzle astronomers. For example, if you look very closely, you can see a faint bluish streak across the centre of this image to the bottom right of the blue region. This could be an asteroid, but seems to be travelling far too quickly for such an object — making this one of the remaining mysteries of the night sky.

Earth from Space: Qeshm Island

This week's edition of the Earth from Space programme features a Copernicus Sentinel-2 image of Qeshm Island – the largest island in Iran.

See also Qeshm Island, Iran to download the image.

Qeshm Island, Iran

A Copernicus Sentinel-2 image over Qeshm Island – the largest island in Iran.

ESA's technical heart

ESA's technical heart

Webb’s golden mirror wings open one last time on Earth

The world’s most powerful space science telescope has opened its primary mirror for the last time on Earth.

As part of the international James Webb Space Telescope’s final tests, the 6.5 meter (21 feet 4 inch) mirror was commanded to fully expand and lock itself into place, just like it would in space. The conclusion of this test represents the team’s final checkpoint in a long series of tests designed to ensure Webb’s 18 hexagonal mirrors are prepared for a long journey in space, and a life of profound discovery. After this, all of Webb’s many movable parts will have confirmed in testing that they can perform their intended operations after being exposed to the expected launch environment.

Making the testing conditions close to what Webb will experience in space helps to ensure the observatory is fully prepared for its science mission one million miles away from Earth.

Commands to unlatch and deploy the side panels of the mirror were relayed from Webb’s testing control room at Northrop Grumman, in Redondo Beach, California. The software instructions sent, and the mechanisms that operated are the same as those used in space. Special gravity offsetting equipment was attached to Webb to simulate the zero-gravity environment in which its complex mechanisms will operate. All of the final thermal blanketing and innovative shielding designed to protect its mirrors and instruments from interference were in place during testing.

Read more.

Webb is an international partnership between NASA, ESA and CSA. The telescope will launch on an Ariane 5 from Europe's Spaceport in French Guiana.

Installing Juice at ESTEC

Installing Juice at ESTEC

Our giant universe

This detailed image features Abell 3827, a galaxy cluster that offers a wealth of exciting possibilities for study. It was observed by Hubble in order to study dark matter, which is one of the greatest puzzles cosmologists face today. The science team used Hubble’s Advanced Camera for Surveys (ACS) and Wide Field Camera 3 (WFC3) to complete their observations. The two cameras have different specifications and can observe different parts of the electromagnetic spectrum, so using them both allowed the astronomers to collect more complete information. Abell 3827 has also been observed previously by Hubble, because of the interesting gravitational lens at its core. 

Looking at this cluster of hundreds of galaxies, it is amazing to recall that until less than 100 years ago, many astronomers believed that the Milky Way was the only galaxy in the Universe. The possibility of other galaxies had been debated previously, but the matter was not truly settled until Edwin Hubble confirmed that the Great Andromeda Nebula was in fact far too distant to be part of the Milky Way. The Great Andromeda Nebula became the Andromeda Galaxy, and astronomers recognised that our Universe was much, much bigger than humanity had imagined. We can only imagine how Edwin Hubble — after whom the Hubble Space Telescope was named — would have felt if he’d seen this spectacular image of Abell 3827.

Morbihan, France

The Copernicus Sentinel-2 mission takes us over Morbihan – a French department in the south of Brittany.

Earth from Space: Morbihan

In this week's edition of the Earth from Space programme, the Copernicus Sentinel-2 mission takes us over Morbihan – a French department in the south of Brittany.

See also Morbihan, France to download the image.

Juice in transport container

Juice in transport container

In the sky with diamonds

The interaction of two doomed stars has created this spectacular ring adorned with bright clumps of gas — a diamond necklace of cosmic proportions. Fittingly known as the Necklace Nebula, this planetary nebula is located 15 000 light-years away from Earth in the small, dim constellation of Sagitta (The Arrow).

The Necklace Nebula — which also goes by the less glamorous name of PN G054.2-03.4 — was produced by a pair of tightly orbiting Sun-like stars. Roughly 10 000 years ago, one of the aging stars expanded and engulfed its smaller companion, creating something astronomers call a “common envelope”. The smaller star continued to orbit inside its larger companion, increasing the bloated giant’s rotation rate until large parts of it spun outwards into space. This escaping ring of debris formed the Necklace Nebula, with particularly dense clumps of gas forming the bright “diamonds” around the ring.

The pair of stars which created the Necklace Nebula remain so close together — separated by only a few million kilometres — that they appear as a single bright dot in the centre of this image. Despite their close encounter the stars are still furiously whirling around each other, completing an orbit in just over a day. 

The Necklace Nebula was featured in a previously released Hubble image, but now this new image has been created by applying advanced processing techniques, making for a new and improved view of this intriguing object. The composite image includes several exposures from Hubble’s Wide Field Camera 3.

Earth from Space: Antofagasta, Chile

This week's edition of the Earth from Space programme features a Copernicus Sentinel-2 image of Antofagasta, a port city in northern Chile,

See also Antofagasta, Chile to download the image.

Hubble celebrates 31st birthday with giant star on the edge of destruction

In celebration of the 31st anniversary of the launching of the NASA/ESA Hubble Space Telescope, astronomers aimed the celebrated observatory at one of the brightest stars seen in our galaxy to capture its beauty.

The giant star featured in this latest Hubble Space Telescope anniversary image is waging a tug-of-war between gravity and radiation to avoid self-destruction. The star, called AG Carinae, is surrounded by an expanding shell of gas and dust — a nebula. The nebula is about five light-years wide, which equals the distance from here to our nearest star, Alpha Centauri.

The huge structure was created from one or more giant eruptions several thousand years ago. The star’s outer layers were blown into space, the expelled material amounting to roughly 10 times the mass of our Sun. These outbursts are typical in the life of a rare breed of star called a Luminous Blue Variable (LBV), a brief unstable phase in the short life of an ultra-bright, glamorous star that lives fast and dies young. These stars are among the most massive and brightest stars known. They live for only a few million years, compared to the roughly 10-billion-year lifetime of our own Sun. AG Carinae is a few million years old and resides 20 000 light-years away inside our Milky Way galaxy. The star’s expected lifetime is between 5 million and 6 million years.

LBVs have a dual personality. They appear to spend years in  semi-quiescent bliss and then they erupt in a petulant outburst, during which their luminosity increases — sometimes by several orders of magnitude. These behemoths are stars in the extreme, far different from normal stars like our Sun. In fact AG Carinae is estimated to be up to 70 times more massive than our Sun and shines with the blinding brilliance of 1 million suns.

Major outbursts such as the one that produced the nebula featured in this image occur a few times during a LBV’s lifetime. A LBV star only casts off material when it is in danger of self-destruction. Because of their massive forms and super-hot temperatures, luminous blue variable stars like AG Carinae are in a constant battle to maintain stability. It’s an arm-wrestling contest between radiation pressure from within the star pushing outward and gravity pressing inward. This arm-wrestling match results in the star’s expanding and contracting. The outward pressure occasionally wins the battle, and the star expands to such an immense size that it blows off its outer layers, like a volcano erupting. But this outburst only happens when the star is on the verge of coming apart. After the star ejects the material, it contracts to its normal (large) size, settles back down, and becomes stable again.

LBV stars are rare: fewer than 50 are known among the galaxies in our local group of neighbouring galaxies. These stars spend tens of thousands of years in this phase, a blink of an eye in cosmic time. Some are expected to end their lives in titanic supernova blasts, which enrich the Universe with the heavier elements beyond iron.

Like many other LBVs, AG Carinae remains unstable. It has experienced lesser outbursts that have not been as powerful as the one that created the present nebula. Although AG Carinae is semi-quiescient now, its searing radiation and powerful stellar wind (streams of charged particles) have been shaping the ancient nebula, sculpting intricate structures as outflowing gas slams into the slower-moving outer nebula. The wind is travelling at up to 1 million kilometres per hour, about 10 times faster than the expanding nebula. Over time, the hot wind catches up with the cooler expelled material, ploughs into it, and pushes it farther away from the star. This “snowplough” effect has cleared a cavity around the star.

The red material is glowing hydrogen gas laced with nitrogen gas. The diffuse red material at upper left pinpoints where the wind has broken through a tenuous region of material and swept it into space. The most prominent features, highlighted in blue, are filamentary structures shaped like tadpoles and lopsided bubbles. These structures are dust clumps illuminated by the star’s light. The tadpole-shaped features, most prominent at left and bottom, are denser dust clumps  that have  been sculpted by the stellar wind. Hubble’s sharp vision reveals these delicate-looking structures in great detail.

The image was taken in visible and ultraviolet light. Hubble is ideally suited for observations in ultraviolet light because this wavelength range can only be viewed from space.

Galactic close-up

This image shows a close-up portrait of the magnificent spiral galaxy NGC 4603, which lies over 100 million light-years away in the constellation of Centaurus (The Centaur). Bright bands of blue young stars make up the arms of this galaxy, which wind lazily outwards from the luminous core. The intricate red-brown filaments threading through the spiral arms are known as dust lanes, and consist of dense clouds of dust which obscure the diffuse starlight from the galaxy.

This galaxy is a familiar subject for Hubble. In the last years of the twentieth century, NGC 4063 was keenly and closely watched for signs of a peculiar class of stars known as Cepheid variables. These stars have a luminosity closely tied to the period with which they darken and brighten, allowing astronomers to accurately measure how far they are from Earth. Distance measurements from Cepheid variables are key to measuring the furthest distances in the Universe, and were one of the factors used by Georges Lemaître and Edwin Hubble to show that the Universe is expanding.

Earth from Space: Laizhou Bay

In this week's edition of the Earth from Space programme, the Copernicus Sentinel-2 mission takes us over the sediment-stained waters in Laizhou Bay, located on the southern shores of the Bohai Sea, on the east coast of mainland China.
See also Laizhou Bay, China, to download the image.

Earth from Space: Space Coast, Florida

In this week's edition of the Earth from Space programme, the Copernicus Sentinel-2 mission takes us over Cape Canaveral, USA, in a region known as the Space Coast. From here, on 22 April 2021, ESA astronaut Thomas Pesquet is planned to return to the International Space Station for his second mission, Alpha.

See also Space Coast, Florida to download the image.

Light bends from the beyond

This extraordinary image from the NASA/ESA Hubble Space Telescope of the galaxy cluster Abell 2813 (also known as ACO 2813) has an almost delicate beauty, which also illustrates the remarkable physics at work within it. The image spectacularly demonstrates the concept of gravitational lensing.

In amongst the tiny dots, spirals and ovals that are the galaxies that belong to the cluster, there are several distinct crescent shapes. These curved arcs of light are strong examples of a phenomenon known as gravitational lensing. The image was compiled using observations taken with the Hubble Space Telescope’s Advanced Camera for Surveys (ACS) and Wide Field Camera 3 (WFC3). 

Gravitational lensing occurs when an object’s mass causes light to bend. The curved crescents and s-shapes of light in this image are not curved galaxies, but are light from galaxies that actually lie beyond Abell 2813. The galaxy cluster has so much mass that it acts as a gravitational lens, causing light from more distant galaxies to bend around it. These distortions can appear as many different shapes, such as long lines or arcs.

This very visual evidence that mass causes light to bend has been famously used as a proof of one of the most famous scientific theories: Einstein’s theory of general relativity.