Romania’s first experiment on the International Space Station is sending drops to collide head-on at controlled speeds inside a cube. Their behaviour intrigues scientists in an environment where gravity, buoyancy, convection, and sedimentation are negligible. The Dropcoal research, short for Drop Coalescence, explores droplet formation in space and on Earth.

There is a journey of fascinating physics behind every raindrop falling to the ground on Earth. Rain is the result of the complex interaction between water and Earth’s gravity, causing drops to change their shape and merge on their way down. Scientists call it coalescence – the process of two or more droplets, bubbles or particles blending to form a single, larger entity.

Dropcoal investigates the interactions between two drops of different liquids, such as water, ethanol and methylene blue, while varying their diameters and speeds, ranging from as slow as white blood cell displacement (0.01 mm/s) to an ant’s velocity (10 mm/s). In this image, the drop on the left is coloured with methylene blue and is merging with the pure water drop coming from the right.

Monitoring how drops interact and merge in weightlessness could shed light on raindrop formation, fuel combustion and material interactions. Astronauts on long space missions could benefit from better understanding how to handle droplets when treating eye, nose and skin issues, as well as preparing injections.

Following the launch on 5 November with SpaceX’s 31st resupply mission to the Space Station, NASA astronaut Don Pettit installed the experiment in the ICE Cubes facility on ESA’s Columbus laboratory module. “This experiment looks at whether droplets merge or bounce off each other, and how fluids mix after these collisions,” explained the astronaut and chemical engineer. Watch Don Pettit talking about the experiment in this video from the International Space Station.

The experiment is already generating the first droplets in microgravity. While a high-speed camera captures images at up to 8000 frames per second, pumps and precision motors control the droplets’ movements. The software uses image recognition to command droplet generation at the right moment.

During the commissioning phase of the experiment, Romanian teams on Earth ran a series of tests to ensure all systems functioned correctly. There are at least 560 planned collisions involving two to five millimetre-sized droplets.

Dropcoal marks an important milestone for Romania, a country that became an ESA Member State in 2011. This is the first experiment developed and built by RISE, the Romanian InSpace Engineering company.

The results of the experiment will be analysed by an international science team led by experts at the National Institute for the Physics of Lasers, Plasma and Radiation in Romania, in collaboration with the Technical University of Darmstadt, Germany, and Carnegie Mellon University in the USA.

Credits: ESA/NASA

ESA astronaut Thomas Pesquet visits the Vega Launch Complex - Zone de lancement Vega (ZLV) at Europe's Space Port in Kourou, French Guiana on 15 June 2022.

Credits: ESA-Manuel Pedoussaut

One of the scientific goals of ESA’s Euclid mission is to chart the expansion history of the Universe. Recent cosmological observations showed that the Universe does not expand at a constant rate; rather, the Universe's expansion is accelerating. Before these observations, scientists thought that all forms of matter and energy in the Universe would only cause the expansion to slow down over time. To explain an accelerating expansion scientists had to introduce a new form of energy. One working hypothesis for this entity is the ‘cosmological constant’ suggested by Albert Einstein in 1917: a constant energy field present across the entire Universe. It is an intrinsic property of the vacuum of space, so the larger the volume of space, the more ‘vacuum energy’ (dark energy) is present and the greater its effects.

There are alternative suggestions. For example, the acceleration could be produced by a fifth fundamental force of nature that evolves with the expansion of the Universe. Contrary to the cosmological constant, this ‘quintessence’ is dynamic, time-dependent and not evenly distributed across space.

Each explanation for what dark energy is subtly alters the way the acceleration changes across cosmic time.

ESA’s Euclid observations will allow scientists to measure how the rate of expansion of the Universe has changed over time and map the last 10 billion years of cosmic history: from cosmic ‘noon’, the time when most stars were forming, until today. This 'looking back in time' will show us the variations in the cosmic acceleration with extreme precision, helping scientists pin down the nature of dark energy.

Euclid is a European mission, built and operated by ESA, with contributions from NASA. The Euclid Consortium is responsible for providing the scientific instruments and scientific data analysis. ESA selected Thales Alenia Space as prime contractor for the construction of the satellite and its service module, with Airbus Defence and Space chosen to develop the payload module, including the telescope. NASA provided the detectors of the Near-Infrared Spectrometer and Photometer, NISP. Euclid is a medium-class mission in ESA’s Cosmic Vision Programme.

Credits: ESA (acknowledgement: work performed by ATG under contract to ESA), CC BY-SA 3.0 IGO

The BepiColombo Mercury Transfer Module, MTM, moving between facilities at Europe's Spaceport in Kourou. Together with JAXA's Mercury Magnetospheric Orbiter and ESA's Mercury Planetary Orbiter, the modules spent the first part of the launch campaign in the 'processing area' before moving to the 'fueling integration area' where the chemical propulsion fueling activities will take place.

Credits: ESA/CNES/Arianespace/Optique video du CSG – P.Baudon

This robotic arm, attached to a 33 m track is ESA's GNC Rendezvous, Approach and Landing Simulator. Part of the Agency's Orbital Robotics and Guidance, Navigation and Control Laboratory, GRALS is used to simulate close approach and capture of uncooperative orbital targets, such as drifting satellites or to rendezvous with asteroids. It can also be used to test ideas for descending to surfaces, such as a lunar or martian landing.

The moveable arm can be equipped with cameras to test vision-based software on a practical basis to close on a scale model of its target. Image-processing algorithms recognise various features on the surface of the model satellite seen here, and uses those features to calculate the satellite’s tumble, allowing the chaser to safely come closer. Alternatively, the robotic arm can be fitted with a gripper, to test out actually securing a target, or with altimeters or other range sensors.

The Orbital Robotics and GNC Lab is located at ESA’s ESTEC technical centre in the Netherlands.

Credits: ESA–M.Grulich

A ground penetrating radar antenna for ESA’s ExoMars 2020 rover being pre-cleaned in an ultra-cleanroom environment in preparation for its sterilisation process, in an effort to prevent terrestrial microbes coming along for the ride to the red planet.

Part of the Agency’s Life, Physical Sciences and Life Support Laboratory based in its Netherlands technical centre, This 35 sq. m ‘ISO Class 1’ cleanroom is one of the cleanest places in Europe. It is equipped with a dry heat steriliser used to reduce the microbial ‘bioburden’ on equipment destined for alien worlds.

The item seen here is the WISDOM (Water Ice Subsurface Deposit Observation on Mars) radar antenna flight model, designed to sound the subsurface of Mars for water ice.

“After pre-cleaning and then the taking of sample swabs, the antenna was placed into our dry heat steriliser, to target the required 99.9% bioburden reduction to meet ExoMars 2020’s cleanliness requirements,” explains technician Alan Dowson.

“To check the effectiveness of this process, the swabs are subjected to a comparable heat shock and then cultivated for 72 hours, to analyse the number of spores and bacteria able to survive. The viable bioburden is then calculated for the surface area of the WISDOM antenna. If this level is below the mission’s maximum then it is cleared for delivery.”

All the cleanroom’s air passes through a two-stage filter system. Anyone entering the chamber has to gown up in a much more rigorous way than a hospital surgeon, before passing through an air shower to remove any remaining contaminants.

The chamber’s cleanliness is such that it contains less than 10 particles smaller than a thousandth of a millimetre per cubic metre. A comparable sample of the outside air could well contain millions.

By international planetary protection agreement, space agencies are legally required to prevent terrestrial microbes hitchhiking to other planets and moons in our Solar System where past or present alien life is a possibility.

Credits: ESA–A. Dowson

How do you prepare for life on the Moon? Start with a flight that bends gravity.

ESA’s 88th parabolic flight campaign took off from Bordeaux, France, for three flights dedicated to lunar gravity research aboard the Airbus A310 Zero-G aircraft. Sponsored by ESA, this campaign gave scientists hands-on time with experiments that will shape how we can live and work on the Moon.

Before leaving Earth, parabolic flights offer a way to simulate the Moon’s gravity—about one-sixth of Earth’s pull. During this lunar campaign, nine experiments tackled big questions, from how blood flows and muscles adapt in partial gravity to how astronauts regain balance and coordination after prolonged immobility.

Research explored how crews could manage injuries without specialists by their side, fire safety in lunar habitats, wearable suits to counteract fluid shifts, and technologies for sorting, moving, and excavating lunar soil to build and extract resources.

Originally designed for astronaut training, parabolic flights now primarily serve science and technology. By flying along a special trajectory, the aircraft creates short periods of reduced gravity, up to 22 seconds of weightlessness for zero-g flights, mimicking the floating experience of the International Space Station, or slightly longer for the partial gravity experienced on the Moons (0.16 g). During these windows, researchers can run experiments in physiology, biology, fluid physics and engineering, gaining insights that ground tests cannot provide.

In the near future, the European Service Module will propel astronauts aboard Orion to the Gateway in lunar orbit and ESA's Argonaut landers will deliver cargo and payloads to the Moon. To make those missions safe and successful, scientists and engineers need to understand how people and technology behave in lunar conditions.

This effort is strengthened by the growing research and testing capabilities of the ESA-DLR LUNA facility in Cologne, Germany—a Moon-analogue environment for surface operations. Soon equipped with a gravity off-loading system to simulate the Moon’s gravity, LUNA will enable astronauts to train for realistic lunar scenarios. These combined ESA initiatives mark a major step toward making future lunar missions safer, smarter and more sustainable.

Credits: Novespace

Last week the second of two solar arrays on the BepiColombo Mercury Transfer Module (MTM) underwent final inspections and deployment before being folded and stowed for launch.

In this image, the solar array is attached to the MTM, which is out of view to the right, and engineers are carefully checking the alignment of the deployed array. Electrical tests and illumination tests were performed before folding the five-panel, 15 metre-long array and tensioning the cables ahead of one last deployment test.

After a final inspection, the solar array was folded again and a temporary protective red cover installed, concluding a successful test phase of the transfer module’s solar arrays.

The MTM will carry the two science orbiters – ESA’s Mercury Planetary Orbiter and JAXA’s Mercury Magnetospheric Orbiter – to the innermost planet using solar electric propulsion along with gravity assist flybys at Earth, Venus and Mercury.

Shortly before arriving at Mercury in 2025, the MTM will separate and the two science orbiters will be captured into orbit together, before separating and moving into their respective orbits. Together they will provide the most up-to-date investigation of the least explored planet in the inner Solar System to date.

For more images of the launch preparations at Kourou visit the BepiColombo image gallery.

Credits: ESA

Many agencies, organisations and companies have contributed to the development of Euclid. This map highlights the main contributing ESA Member States and funding agencies.

- Belgium – Belgian Science Policy Office

- Denmark – National Space Institute

- France – National Centre for Space Studies (CNES)

- Finland – University of Helsinki

- Germany – German Space Agency at DLR

- Italy – Italian Space Agency (ASI)

- Netherlands – Netherlands Research School for Astronomy (NOVA)

- Norway – Norwegian Space Centre

- Portugal – Portuguese Space Agency

- Romania – Romanian Space Agency

- Spain – Ministry of Economy and Competitiveness

- Switzerland – Swiss Space Office

- United Kingdom – UK Space Agency

The National Aeronautics and Space Administration (NASA) of the United States has also contributed to the project by providing the detectors of the Near-Infrared Spectrometer and Photometer (NISP).

Scientists from more than 300 institutes are part of the Euclid Collaboration and will participate in the scientific harvest of the mission.

Euclid is ESA’s space telescope designed to explore the dark Universe. The mission will create the largest, most accurate 3D map of the Universe ever produced across 10 billion years of cosmic time. Euclid will explore how the Universe has expanded and how large-scale structure is distributed across space and time, revealing more about the role of gravity and the nature of dark energy and dark matter.

Credits: ESA (acknowledgement: work performed by ATG under contract to ESA), CC BY-SA 3.0 IGO

A three-stage rocket ship – call it Geryon or the X-49 – will eventually be assembled. The large first stage will be put on top of a blast deflector – a yawning hole into which the rocket motors can discharge their exhaust blast. Then the second stage will be put on top of the first, and finally a delta-winged third stage will be placed on top of the second stage.

But first a two-stage ship will be tested, as shown in the illustration. Each stage has wings along with its own pilot and co-pilot. The pilot of the first stage, after the upper delta-winged stage has blasted away from it, will gradually put the rocket into level flight and keep it aloft until air resistance has killed off its high speed. He might even succeed in flying in an enormous circle so that his ship becomes subsonic again for landing.

“The piloted upper stage, in the meantime, has left the atmosphere along a tremendous arc, reaching a peak of 300 or 400 miles above sea level, and more than 2,500 miles from home base. Some 5,000 miles from home base the upper stage re-enters the atmosphere and lands at a base prepared in a suitable location. After this preparation the crew is ready for the three-stage ship, where the upper stage of the two-stage ship is the third stage.”

[Summarizing and Quoting from the text]

Preparing the Eutelsat Quantum satellite for transport from the S5B facility to the Final Assembly Building (BAF) and the hoist onto the Ariane 5 launcher, at Europe's Space Port in Kourou, French Guyana on 21 July 2021.

Quantum, the ESA Partnership Project with Eutelsat, Airbus and Surrey Satellite Technology Ltd, is a pioneering mission preparing the way for the next generation of telecommunications satellites, which will be more flexible by design and so more adaptable to customer needs once in orbit.

Quantum is a shift from custom-designed satellite with one-off payloads to a more generic approach, resulting in unprecedented in-orbit reconfigurability in coverage, frequency and power, allowing complete mission rehaul, including orbital position.

ESA partnered with satellite operator Eutelsat and manufacturer Airbus to design this programme, in response to today's market requiring satellites to be able to respond to changes in geographical or performance demand, either during manufacturing or after launch. This will enable the operator to address emerging business opportunities — even those that appear after it has ordered a satellite.

Such ESA Partnership Projects maximise the benefits to industry thanks to an efficient, co-managed approach that is tailored to commercial best practice.

Credits: ESA - M. Pedoussaut

This colour-coded topographic image shows a feature on Mars’ surface named Moreux crater, based on data gathered by the Mars Express High Resolution Stereo Camera on 30 October 2019 during orbit 20014. This view is based on a digital terrain model (DTM) of the region, from which the topography of the landscape can be derived; lower parts of the surface are shown in blues and purples, while higher altitude regions show up in whites, yellows and reds, as indicated on the scale to the bottom left. North is to the right.

Credits: ESA/DLR/FU Berlin, CC BY-SA 3.0 IGO

Alone in a remote Norwegian fjord, the explorers discuss the best route to discovery looking at the science plans with Moon science in mind. Before setting off, they use a tablet that holds a universe of information: detailed geological maps pop up along with colourful spectral images from satellites and messages from the science team.

The three explorers pictured are ESA astronaut Thomas Pesquet, NASA’s Jessica Wittner and Arnaud Prost, a member of the ESA Astronaut Reserve who joined as a CNES member of the EAC integrated team.

They are part of the latest edition of ESA’s PANGAEA geology training in Lofoten, Norway. Once buried beneath massive ice sheets and glaciers, this region was carved over thousands of years into dramatic peaks and valleys.

The team chose this location because of the presence of an unusual crystalline rock – anorthosite. While anorthosite is hard to find on Earth, it makes up a significant part of the Moon’s surface, especially in the heavily cratered regions of the lunar highlands.

The trainees are using the Electronic Field Book to decide where to go. Developed by ESA, this system helps them document their scientific findings and update a geological map as they scout the area. Here is a video of how mapping forward to the Moon works.

To support the astronauts in the field, the science team created a specialised set of maps using data from drone flights. These maps include spectral signatures – the unique fingerprints of the rocks – which help pinpoint where rocks of different compositions meet, guiding the astronauts to the most scientifically interesting areas.Once the astronauts choose their path, they are left to explore independently with just a microscope, a spectrometer, and a set of geological tools. Instructors encourage them to pay close attention to subtle details to find clues that can reveal the bigger geological picture hidden in the landscape.

As they move through the terrain, the trainees must verify with the ground team whether what they observe matches the information provided by the scientists.

Thomas, Jessica, and Arnaud used this process to learn how the anorthosites formed and identified striking parallels with those found on the lunar surface. The exercise also helped scientists improve the geological map of the area.

On the Moon, astronauts will serve as the eyes and hands of scientists on Earth. Through PANGAEA, astronauts learn how to observe, describe, and document geological features. Understanding what matters to scientists on the ground is essential for the success of future exploration missions.

Find more information and updates about this training on ESA’s PANGAEA blog.

Credits: ESA/V. Crobu

In preparation for his Beyond mission, ESA astronaut Luca Parmitano was at the Johnson Space Center in Houston, USA, in March 2019.

His training included working on a spacewalk, or Extravehicular Activity (EVA).

Luca already has two spacewalks under his belt but in ‘building 9’ of the Johnson Space Center, Luca worked with the Space Vehicle Mockup Facility and refreshed his skills on maintaining the US spacewalk suits called Extravehicular Mobility Units (EMU).

The training is important as Luca has some spacewalks planned that will see him repair the Alpha Magnetic Spectrometer AMS-02 particle detector. The dark-matter hunter was launched 16 May 2011 on Space Shuttle Endeavour mission STS-134. It records over 17 billion cosmic rays, particles, and nuclei a year. The results from AMS-02 have shown unexpected phenomena not predicted by cosmic ray models—and changing our understanding of the cosmos.

The mission was initially meant to run for only three years but has been so successful that its mission life has been extended. Three of the four cooling pumps however have stopped functioning and require repair.

A series of spacewalks are planned to replace the cooling system for the $2 billion instrument but they were never designed to be replaced in space.

The first spacewalk is intended to determine just how and where to intervene, and what tools will be needed for the process.

Luca will go beyond Earth’s atmosphere when he returns to the International Space Station in 2019 as part of Expedition 60/61, alongside NASA astronaut Andrew Morgan and Roscosmos astronaut Alexander Skvortsov.

Luca was the first of the 2009 astronaut class to fly to the Space Station. His first mission Volare, meaning 'to fly' in Italian, took place in 2013 and lasted 166 days, during which time Luca conducted two spacewalks and many experiments that are still running today.

Credits: ESA - S. Corvaja

A team of astronomers has taken the sharpest-ever picture of the unexpected interstellar comet 3I/ATLAS, using the crisp vision of the NASA/ESA Hubble Space Telescope.

ESA's Planetary Defence Office responded promptly to the discovery of the comet, and has been tracking it since the beginning of July.

Now, Hubble's observations from space are allowing astronomers to more accurately estimate the size of the comet’s solid icy nucleus. The upper limit on the diameter of the nucleus is 5.6 km, but it could be as small as 320 m across, researchers report.

Though the Hubble images put tighter constraints on the nucleus size compared to previous ground-based estimates, the solid heart of the comet presently cannot be directly seen, even by Hubble. Further observations, including by the NASA/ESA/CSA James Webb Space Telescope, will help refine our knowledge about the comet, including its chemical makeup.

Hubble also captured a dust plume ejected from the Sun-warmed side of the comet, and the hint of a dust tail streaming away from the nucleus. Hubble’s data show that the comet is losing dust in a similar manner to that from previously seen Sun-bound comets originating within our Solar System.

The big difference is that this interstellar visitor originated in some other stellar systems, elsewhere in our Milky Way galaxy.

3I/ATLAS is traveling through our Solar System at roughly 210 000 km per hour, the highest speed ever recorded for a Solar System visitor. This breathtaking sprint is evidence that the comet has been drifting through interstellar space for many billions of years. The gravitational slingshot effect from innumerable stars and nebulae the comet passed added momentum, ratcheting up its speed. The longer 3I/ATLAS was out in space, the higher its speed grew.

This comet was discovered by the Asteroid Terrestrial-impact Last Alert System (ATLAS) on 1 July 2025 at a distance of 675 million km from the Sun. 3I/ATLAS should remain visible to ground-based telescopes until September, after which it will pass too close to the Sun to observe. It is expected to reappear on the other side of the Sun by early December.

Icy wanderers such as 3I/ATLAS offer a rare, tangible connection to the broader galaxy. To actually visit one would connect humankind with the Universe on a far greater scale. To this end, ESA is preparing the Comet Interceptor mission. The spacecraft will be launched in 2029 into a parking orbit, lying in wait for a suitable target – a pristine comet from the distant Oort Cloud that surrounds our Solar System, or, unlikely but highly appealing, an interstellar object.

While it is improbable that we will discover an interstellar object that is reachable for Comet Interceptor, as a first demonstration of a rapid response mission that waits in space for its target, it will be a pathfinder for possible future missions to intercept these mysterious visitors.

The research paper based on Hubble observations will be published in The Astrophysical Journal Letters.

[Image description: At the center of the image is a comet that appears as a teardrop-shaped bluish cocoon of dust coming off the comet’s solid, icy nucleus and seen against a black background. The comet appears to be heading to the bottom left corner of the image. About a dozen short, light blue diagonal streaks are seen scattered across the image, which are from background stars that appeared to move during the exposure because the telescope was tracking the moving comet.]

Credits:

NASA, ESA, D. Jewitt (UCLA), J. DePasquale (STScI); CC BY 4.0

A 3D-printed ExoMy rover modelled after ESA’s Rosalind Franklin rover navigates towards a blue ball on Mars-like terrain. This scene took place at ESA Academy’s recent Robotics Workshop, where thirty university students spent four days diving into space robotics at the European Space Research and Technology Centre (ESTEC) in Noordwijk, the Netherlands.

Lennart Puck, an internal research fellow at ESA’s Planetary Robotics Lab, provided support for the students as they learned to operate the ExoMy rovers. “Robots are a part of our daily work,” he says. “However, the students are from different, non-robotics backgrounds. So, in the workshop, we tried to show them step-by-step how robotic systems work.”

“We started with ExoMy’s hardware system,” Lennart explains. “First the students had to correctly connect the motors and calibrate the system before they could drive the robot around.”

As the workshop progressed, students explored software development, locomotion strategies, and used machine learning to train their rovers in object recognition.

On the last day of the workshop, it was time to take hands off the controllers and let the robots do the work. The assignment: an autonomous exploration mission where the ExoMy rovers were tasked with finding an object of interest – a blue ball – hidden somewhere in the Mars-like terrain.

According to Lennart this assignment mimics some of the challenges a rover faces on Mars. “Direct remote control between Earth and Mars isn’t feasible,” he says. “In the best case, we have around four minutes delay. In the worst case, it’s over twenty minutes each way.” This means that, like the ExoMy robots during their final challenge, the Rosalind Franklin rover must be able to independently navigate and identify objects without direct interaction with a human controller.

In addition to the hands-on experience of operating ExoMy, the workshop also gave students an overview of the field of space robotics, with lectures from various ESA experts and a tour of ESTEC. “We are not just computer engineers, mechanical engineers and electrical engineers,” comments Lennart. “There are many different backgrounds needed in robotics. But the main thing I hope students take away is that working with robots is fun.”

[Image description: This is a photograph of a 3D-printed robot with six wheels. The body of the robot is a black rectangular box with the ESA logo on the side. A wide yellow head with big eyes, a short orange beak, and a green lighting-shaped antenna sits on top of a narrow neck at the front of the robot. The robot is moving down a small incline on an orange carpet and appears to be looking at a blue ball sitting on the carpet. The background is blurred. On the left, a student is holding a remote control and looking towards the robot as other students watch. A small group of students on the right are standing in a small circle. Behind the students sits a large silver cylinder tipped on its side – a model of the Columbus laboratory of the International Space Station. In the back, right corner is a white model of a rocket.]

Credits: ESA-SJM Photography

Rollout to the launch pad of the Soyuz rocket with the Soyuz MS-09 spacecraft inside, 4 June 2018. The spacecraft will launch ESA astronaut Alexander Gerst into space alongside NASA astronaut Serena Auñón-Chancellor and Roscosmos commander Sergei Prokopyev from the Baikonur cosmodrome in Kazakhstan on 6 June.

The 50-m tall Soyuz rocket will propell the astronauts to their cruising speed of around 28 800 km/h. Within 10 minutes of rising from the pad, the trio travelled over 1640 km and gained 210 km altitude. Every second for nine minutes, their spacecraft accelerated 50 km/h on average.

The rocket is rolled to the launch pad on a train, the astronauts are not allowed to see this part of the launch preparation – it is considered bad luck.

This will be Alexander’s second spaceflight, called Horizons. He will also be the second ESA astronaut to take over command of the International Space Station. The Horizons science programme is packed with European research: over 50 experiments will deliver benefits to people on Earth as well as prepare for future space exploration.

Credits: ESA - S. Corvaja

The BepiColombo 'ministack', comprising JAXA's Mercury Magnetospheric Orbiter (top) and ESA's Mercury Planetary Orbiter (bottom), transferring between facilities at Europe's Spaceport in Kourou. The modules spent the first part of the launch campaign in the 'processing area' before moving to the 'fueling integration area' where the chemical propulsion fueling activities will take place.

Credits: ESA–B.Guillaume

ExoMars is a joint endeavour between ESA and Roscosmos. The rover is part of the 2020 mission, landing on Mars with a surface science platform in 2021.

Credits: ESA - S. Corvaja

This is one of a series of images taken by the ESA/JAXA BepiColombo mission on 8 January 2025 as the spacecraft sped by for its sixth and final gravity assist manoeuvre at the planet.

Monitoring camera 2 (M-CAM 2) took this photo at 07:17 CET, when the spacecraft was about 2103 km from the planet’s surface. The spacecraft’s closest approach of 295 km took place on the planet's night side at 06:59 CET.

The bright patch near the planet's upper edge in this image is the Nathair Facula, the aftermath of the largest volcanic explosion on Mercury. At its centre is a volcanic vent of around 40 km across that has been the site of at least three major eruptions. The explosive volcanic deposit is at least 300 km in diameter.

Nathair Facula is a major target for several BepiColombo instruments, which will measure the composition of the erupted material. This will teach us about what Mercury is made of, and how the planet formed.

Also visible is the relatively young Fonteyn crater, which formed a ‘mere’ 300 million years ago. Its youth is apparent from the brightness of the impact debris that radiates out from it. Older material on Mercury's surface has become much darker from weathering as it aged.

Rustaveli, seen roughly in the centre of Mercury in this image, is about 200 km in diameter. Within its rim is a ring of peaks, making it a so-called peak ring basin. These peaks barely poke above smooth material on Rustaveli’s floor, which suggests the crater has been flooded by lava.

Interestingly, NASA’s Messenger spacecraft detected a magnetic signal coming from Rustaveli. When molten rock such as lava or impact melt solidifies, magnetic carriers within it align with the direction of the planet's magnetic field. As the planetary magnetic field naturally changes over time, eventually the 'locked in' magnetic field in the planet's crust no longer agrees with the planetary magnetic field, something that can be detected from space. BepiColombo's two magnetometer instruments will investigate this further.

In the foreground of the image, the Mercury Planetary Orbiter’s medium gain antenna (top centre) and magnetometer boom (right) are visible.

[Technical details: This image of Mercury's surface was taken by M-CAM 2 onboard the Mercury Transfer Module (part of the BepiColombo spacecraft), using an exposure time of 4 millseconds. Taken from a distance of around 2103 km, the surface resolution in this photograph is around 2330 m/pixel. The image has been lightly processed; its brightness and contrast have been adjusted.]

[Image description: Planet Mercury in the background with its grey, cratered, pockmarked surface. In the foreground are some spacecraft parts.]

Credits: ESA/BepiColombo/MTM; CC BY-SA 3.0 IGO

Asteroid 2025 TF flew over Antarctica at 00:47:26 UTC ± 18 s on 1 October, coming as close as 428 ± 7 km to Earth’s surface. This is a similar altitude to the orbit of the International Space Station (approx. 370—460 km).

The asteroid is roughly 1 to 3 metres across and was first spotted by the Catalina Sky Survey a few hours after it had passed Earth. Objects of this size pose no significant danger. They can produce fireballs if they strike Earth’s atmosphere, and may result in the discovery of small meteorites on the ground.

Astronomers in ESA’s Planetary Defence Office observed the object shortly after its discovery, using the Las Cumbres Observatory telescope in Siding Spring, Australia.

Tracking down a metre-scale object in the vast darkness of space at a time when its location is still uncertain is an impressive feat. This observation helped astronomers determine the close approach distance and time given above to such high precision.

Credits: ESA / Las Cumbres Observatory

Acknowledgements: T. Santana-Ros, M. Micheli, F. Ocaña, M. Devogèle, L. Conversi, R. Kresken

The Ariane 6 launch pad at Europe’s Spaceport in French Guiana now hosts the first example of ESA’s new heavy-lift rocket. This Ariane 6 combined tests model will be used to validate the entire launch system during its ground phase in readiness for the inaugural launch of Ariane 6.

The combined tests include filling tanks, and draining them in case of launch abort, count-down automated sequence, and cryogenic arms disconnection and retraction at a simulated liftoff.

These tests will be carried out under ESA’s authority by an integrated team from ESA, ArianeGroup and French space agency CNES.

The Ariane 6 combined tests model is highly representative of the flight model. It consists of the core stage and the upper stage, which make up the central core, as well as three pylons shaped like the rocket’s solid boosters and a fully representative but inert mockup of the fourth booster.

The Ariane 6 combined tests model central core was precisely mated in the purpose-built launcher assembly building, where this task is carried out horizontally. Automated guidance vehicles then brought the assembled core to the launch and, working with the crane at the mobile gantry, raised it to its vertical position.

Ariane 6 is a modular launch vehicle using either two or four P120C strap-on boosters, depending on mission requirements. The P120C engine does double duty, also serving as the first stage of ESA’s new Vega-C rocket.

The reignitable Vinci engine which powers the upper stage allows Ariane 6 to deliver multiple payloads to different orbits on a single launch. After payload separation a final engine burn deorbits the upper stage so that it does not become a debris threat in space. 

Ariane 6 development is project-managed and funded by ESA, which also acts as launch system architect. ArianeGroup is design authority and industrial prime contractor for the launcher system and CNES is prime contractor for the Ariane 6 launch base at Europe’s Spaceport. Arianespace is the launch service provider of Ariane 6. 

Credits: ESA - S. Corvaja

One of the five bodies circling the earth is the third stage of a rocket ship manned by three men. The other four bodies are the “cargo pods” of other rocket ships. And one more pod is on the way.

The principle of operation is this. . . “If a large amount of material has to be carried into an orbit it is not necessary to carry every pound of it in manned ships. The cheapest way is to put the material into the cargo pods of unmanned ships. However, remote control from the ground could not get a number of cargo pods together in the same place. Therefore, a manned ship must be in the orbit all the time to direct the unmanned cargo pods by remote control.” [Summarizing and Quoting from the text]

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Image description: The Moon is seen moving away from planet Earth.

The Moon is slowly moving away from Earth, about 4 cm farther away each year.

Gravity and tidal forces between these two celestial bodies are slowing down the rotation of Earth and increasing the distance from each other.

Missions to the Moon will help us understand how it was created and learn more about its orbit.

#ForwardToTheMoon

Credits: ESA

ESA Astronaut Luca Parmitano in the Gagarin Cosmonaut Training Center near Moscow, Russia, 19 June 2019 wearing the Sokol suit he will wear when he is launched to the International Space Station. Sokol suits, tailored to each astronaut, are worn in the Soyuz spacecraft as protection against air leaks.

Luca is training for his Beyond mission which will see him return to the International Space Station in 2019 as part of Expedition 60/61, alongside NASA astronaut Andrew Morgan and Roscosmos cosmonaut Alexander Skvortsov.

Luca was the first of ESA’s 2009 astronaut class to fly to the International Space Station. His first mission Volare, meaning 'to fly' in Italian, took place in 2013 and lasted 166 days. Luca conducted two spacewalks and many experiments that are still running today.

Connect with Luca

Credits: ESA - S. Corvaja

The Ariane 6 launch pad at Europe’s Spaceport in French Guiana now hosts the first example of ESA’s new heavy-lift rocket. This Ariane 6 combined tests model will be used to validate the entire launch system during its ground phase in readiness for the inaugural launch of Ariane 6.

The combined tests include filling tanks, and draining them in case of launch abort, count-down automated sequence, and cryogenic arms disconnection and retraction at a simulated liftoff.

These tests will be carried out under ESA’s authority by an integrated team from ESA, ArianeGroup and French space agency CNES.

The Ariane 6 combined tests model is highly representative of the flight model. It consists of the core stage and the upper stage, which make up the central core, as well as three pylons shaped like the rocket’s solid boosters and a fully representative but inert mockup of the fourth booster.

The Ariane 6 combined tests model central core was precisely mated in the purpose-built launcher assembly building, where this task is carried out horizontally. Automated guidance vehicles then brought the assembled core to the launch and, working with the crane at the mobile gantry, raised it to its vertical position.

Ariane 6 is a modular launch vehicle using either two or four P120C strap-on boosters, depending on mission requirements. The P120C engine does double duty, also serving as the first stage of ESA’s new Vega-C rocket.

The reignitable Vinci engine which powers the upper stage allows Ariane 6 to deliver multiple payloads to different orbits on a single launch. After payload separation a final engine burn deorbits the upper stage so that it does not become a debris threat in space. 

Ariane 6 development is project-managed and funded by ESA, which also acts as launch system architect. ArianeGroup is design authority and industrial prime contractor for the launcher system and CNES is prime contractor for the Ariane 6 launch base at Europe’s Spaceport. Arianespace is the launch service provider of Ariane 6. 

Credits: ESA - S. Corvaja

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The surface of the Moon is quite dark. The colour of the lunar landscape is mostly charcoal-grey. The Moon reflects the light of the Sun.

Seen from Earth, the atmosphere scatters certain wavelengths of light. When the Moon is close to the horizon, it often looks reddish. As it goes higher in the sky and is less obscured by the atmosphere, the Moon appears more yellow.

Image description: Paint brush with dark grey emulsion over Moon.

Credits: ESA

ESA's newly selected astronaut candidates of the class of 2022 arrived at the European Astronaut Centre in Cologne, Germany, on 3 April 2023 to begin their 12-month basic training.

The group of five candidates, Sophie Adenot, Pablo Álvarez Fernández, Rosemary Coogan, Raphaël Liégeois, and Marco Sieber, are part of the 17-member astronaut class of 2022, selected from 22 500 applicants from across ESA Member States in November 2022.

The astronaut candidates will be trained to the highest level of standards in preparation for future space missions. During basic training, this includes learning all about space exploration, technical and scientific disciplines, space systems and operations, as well as spacewalk and survival training.

This image shows the candidates an Australian astronaut candidate Katherine Bennell-Pegg, joining the group under agreement with Australian Space Agency, on their first day at the European Astronaut Centre, ready to embark on their journey to become certified ESA astronauts.

Credits: ESA-S. Corvaja

After arrival at the cleanroom at ESTEC, the European Space Agency’s Plato spacecraft was moved to a tent providing the clean air needed for its sensitive optical instruments. Here it is still covered by a protective film. The spacecraft can be seen in horizontal transport configuration on a rolling platform.

[Image description: Inside a cleanroom, several individuals wearing protective clothing and hairnets are working around a large spacecraft. The spacecraft has gold and black colours and is wrapped in plastic sheeting, and mounted on a white transport platform. The background features metallic walls, blue structural elements, and various pieces of laboratory equipment, contributing to the high-tech, clean environment.]

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Credits: ESA-SJM Photography

Two views of Jupiter showcase the wealth of information provided by the spectral filters on the Hubble Space Telescope’s Wide Field Camera 3 (WFC3) science instrument. At left, the RGB composite is created using three filters at wavelengths similar to the colors seen by the human eye. At right, the wavelength bounds are widened beyond the visible range to extend just into the ultraviolet (UV) and infrared regimes. Humans cannot perceive these extended wavelengths, but some animals are able to detect infrared and ultraviolet light. The result is a vivid disk that shows UV-absorbing lofty hazes as orange (over the poles and in three large storms, including the Great Red Spot), and freshly-formed ice as white (compact storm plumes just north of the equator). Astronomers, including the OPAL team, use these filters (and others not shown here) to study differences in cloud thickness, altitude, and chemical makeup.

[Image description: A two-panel image labeled “Jupiter, January 5, 2024, HST WFC3/UVIS” showcases the wealth of information provided by the spectral filters on the Hubble’s Wide Field Camera 3 (WFC3) science instrument. At left, this Hubble image of Jupiter is created using three filters at wavelengths similar to the colors seen by the human eye: F395N is blue, F502N is green, F658N is red. At right, the wavelength bounds are widened beyond the visible range to extend just into the ultraviolet (UV) and infrared regimes: F343N is blue, F467M is green, FQ889N is red. Humans can’t perceive these extended wavelengths. The result is a vivid disk that shows UV-absorbing lofty hazes as orange (over the poles and in three large storms, including the Great Red Spot), and freshely-formed ice as white (compact storm plumes just north of the equator). These filters (and others not shown here) allow astronomers to study differences in cloud thickness, altitude, and chemical makeup.]

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Credits:NASA, ESA, A. Simon (NASA-GSFC), M. H. Wong (UC Berkeley), J. DePasquale (STScI); CC BY 4.0

This Proba-V view shows all that is left of the Aral Sea, once one of the four largest lakes in the world and now one of the world’s major ecological disaster areas. It has shrunk into separate lakes, surrounded by Earth’s youngest desert.

The Aral Sea was once a large land-locked lake between Kazakhstan in the North and Uzbekistan in the South, possessing an area of 68 000 sq. km – twice that of Belgium.

However, the Aral Sea has dramatically shrunk since the 1960s when Soviet irrigation projects diverted water from the rivers supplying it. By the 2000s, the lake had shrunk to about 10% of its original size and by 2014 the horseshoe-shaped Southern Lake had virtually dried up.

Groundwater levels also fell, vegetation was laid waste and a once-thriving fishing industry collapsed. The exposed lakebed formed the newly-christened Aralkum Desert, spawning pesticide-laced sandstorms that can reach as far as the Himalayas.

Efforts to stabilise the situation are ongoing, including the replanting of hardy vegetation to reduce sandstorms. In 2005, the Kok-Aral Dam was completed to restore water levels in the Northern Lake –located at its bottom-east side. In addition, a sluice is periodically opened to replenish the Southern Lake.

Launched on 7 May 2013, Proba-V is a miniaturised ESA satellite tasked with a full-scale mission: to map land cover and vegetation growth across the entire planet every two days.

Its main camera’s continent-spanning 2250 km swath width collects light in the blue, red, near-infrared and mid-infrared wavebands at 300 m resolution and down to 100 m resolution in its central field of view.

VITO Remote Sensing in Belgium processes and then distributes Proba-V data to users worldwide. An online image gallery highlights some of the mission’s most striking images so far, including views of storms, fires and deforestation.

This 100 m-resolution image was acquired on 15 June 2018.

Proba-V is currently the subject of ESA’s latest ‘citizen science’ competition, requesting teams to produce ‘super-resolution’ images equivalent to its 100 m mode from sets of 300 m imagery.

Credits: ESA/Belspo – produced by VITO

Cosmic radiation could increase cancer risks during long duration missions. Damage to the human body extends to the brain, heart and the central nervous system and sets the stage for degenerative diseases. A higher percentage of early-onset cataracts have been reported in astronauts.

Earth’s magnetic field and atmosphere protect us from the constant bombardment of galactic cosmic rays – energetic particles that travel at close to the speed of light and penetrate the human body.

A second source of space radiation comes from unpredictable solar particle events that deliver high doses of radiation in a short period of time, leading to ‘radiation sickness’ unless protective measures are taken.

Credits: ESA

ESA’s newly approved Lunar Meteoroid Impact Observer, Lumio, mission will orbit an Earth-Moon Lagrange point to detect meteoroid flashes on the night-time lunar farside. In addition Lumio will also perform an innovative autonomous navigation experiment – using its camera images to calculate the spacecraft’s current orbital position and distance from the Moon.

Shown here is the new variable magnification, hardware-in-the-loop testbed being used to develop and test the necessary vision-based navigation algorithms to accomplish this ambitious task. Known as ‘Retina’, or Realistic Experimental FaciliTy for vision-based Navigation, it is composed of several opto-mechanical parts installed along two parallel optical lines in an optical bench in a darkroom.

Both lines replicate the same setup. A high-resolution, high dynamic range microdisplay screen displaying synthetic scenes of the Moon is linked to a ‘collimator’ lens system that can project the observed scenes at infinity, a relay lens assembly to achieve variable magnification capabilities and a camera instrument mimicking the charactistics of real vision-based systems.

Retina has been developed by the Deep-space Astrodynamics Research and Technology, DART, group at Politecnico di Milano’s Department of Aerospace Science and Technology, overseeing the Lumio project for ESA.

Francesco Topputo, Professor of Space Science at Politecnico di Milano, explains: “If this experiment can indeed determine Lumio’s position without any ground station in the loop, it would pave the way for low-cost autonomous navigation in cislunar space.”

Lumio is a briefcase-sized 12-unit ‘CubeSat’ – a low-cost small spacecraft built up from standardised 10 cm boxes – which will be placed in orbit around the Earth-Moon Lagrange Point 2, a point of gravitational equilibrium between the two bodies.

The mission was one of two winning concepts from the ESA SysNova Lunar CubeSats for Exploration challenge which has now been given funding through the ‘Fly’ Element of ESA’s General Support Technology Programme, aimed at early demonstration of promising technology in space.

Lumio is being put together for ESA by a consortium including Politecnico di Milano, Argotec, Leonardo, IMT- Ingegneria Marketing Tecnologia, Nautilus, ECAPS, LMO and S&T Norway.

Credits: Politecnico di Milano

Europe’s newest rocket, Ariane 6, took flight for the second time from Europe’s Spaceport in French Guiana at 13:24 local time on 6 March (16:24 GMT, 17:24 CET).

This was the first commercial flight for Ariane 6, flight VA263, delivering the CSO-3 satellite to orbit. Arianespace was the operator and launch service provider for the French Procurement agency (DGA) and France’s space agency CNES on behalf of the French Air and Space Force’s Space Command (CDE).

During this second launch, all phases were successfully executed, including the Auxiliary Propulsion Unit (APU) reignition, the Vinci engine’s third boost and deorbiting of the upper stage.

Ariane 6 is Europe’s heavy launcher and a key element of ESA’s efforts to ensure autonomous access to space for Europe’s citizens. Its modular and versatile design allows it to launch all missions from low-Earth orbit into deep space. For this launch, the rocket was used in its two-booster configuration.

Shortly after liftoff and booster separation, the upper stage separated from the core stage. The upper stage engine then fired for the first time, taking Ariane 6 into an elliptical orbit travelling 300 km at its closest to Earth, and 600 km at its farthest from Earth, achieving the ‘chill-down’ and first ignition of the Vinci engine and of the Auxiliary Propulsion Unit. After a ‘coasting’ phase lasting 37 minutes, the engine fired up for a second time.

After Vinci’s second boost, the rocket’s passenger, a French satellite called CSO-3, was injected into Sun-Synchronous Orbit at an altitude of around 800 km. Spacecraft separation occurred one hour and six minutes after liftoff.

After the successful delivery of CSO-3, Ariane 6 demonstrated the full potential of its upper stage. The Auxiliary Propulsion Unit ignited as expected, and the Vinci engine’s third boost put the upper stage into a reentry orbit to safely burn up through Earth’s atmosphere, preventing accumulation of space debris. This confirms the full capability of Ariane 6.

Credits: ESA-S. Corvaja

Ariane 6 launches to the sky on 9 July 2024 from Europe's Spaceport in French Guiana.

Europe’s newest heavy-lift rocket, it is designed to provide great power and flexibility at a lower cost than its predecessors. The launcher’s configuration – with an upgraded main stage, a choice of either two or four powerful boosters and a new restartable upper stage – will provide Europe with greater efficiency and possibility as it can launch multiple missions into different orbits on a single flight, while its upper stage will deorbit itself at the end of mission.

Credits: ESA - S. Corvaja

Ariane 5 VA 260 with Juice, start of rollout on Tuesday 11 April.

Juice is being prepared to launch from Europe’s Spaceport in Kourou, French Guiana, on 13 April 2023.

Juice – JUpiter ICy moons Explorer – is humankind’s next bold mission to the outer Solar System. This ambitious mission will characterise Ganymede, Callisto and Europa with a powerful suite of remote sensing, geophysical and in situ instruments to discover more about these compelling destinations as potential habitats for past or present life. Juice will monitor Jupiter’s complex magnetic, radiation and plasma environment in depth and its interplay with the moons, studying the Jupiter system as an archetype for gas giant systems across the Universe.

Following launch, Juice will embark on an eight-year journey to Jupiter, arriving in July 2031 with the aid of momentum and direction gained from four gravity-assist fly-bys of the Earth-Moon system, Venus and, twice, Earth.

Flight VA260 will be the final Ariane 5 flight to carry an ESA mission to space.

Find out more about Juice in ESA’s launch kit

Credits: ESA - S. Corvaja

The BepiColombo spacecraft stack is transported for mounting in the launcher.

BepiColombo is a joint endeavour between ESA and JAXA, the Japan Aerospace Exploration Agency. JAXA’s Mercury Magnetospheric Orbiter is seen at the top of the stack, ESA’s Mercury Planetary Orbiter is in the middle, and ESA’s Mercury Transfer Module is at the bottom.

Credits: ESA - M. Pedoussaut

Europe’s first MetOp Second Generation, MetOp-SG-A1, weather satellite – which hosts the Copernicus Sentinel-5 mission – has launched aboard an Ariane 6 rocket from the European spaceport in French Guiana. The rocket lifted off on 13 August at 02:37 CEST (12 August 21:37 Kourou time).

MetOp-SG-A1 is the first in a series of three successive pairs of satellites. The mission as a whole not only ensures the continued delivery of global observations from polar orbit for weather forecasting and climate analysis for more than 20 years, but also offers enhanced accuracy and resolution compared to the original MetOp mission – along with new measurement capabilities to expand its scientific reach.

This new weather satellite also carries the Copernicus Sentinel-5 mission to deliver daily global data on air pollutants and atmospheric trace gases as well as aerosols and ultraviolet radiation.

Ariane 6 is Europe’s heavy launcher and a key element of ESA’s efforts to ensure autonomous access to space for Europe’s citizens. Ariane 6 has three stages: two or four boosters, and a main and upper stage. For this flight, VA264, the rocket was used in its two-booster configuration.

Credits: ESA - S.Corvaja

A special test campaign undertaken in this ESA lab well before the launch of the Agency’s Euclid mission to explore the dark Universe has helped support an important manoeuvre that the newly-launched spacecraft is currently undertaking in space.

On 4 July, as Euclid headed on to its set observing point in space, 1.5 million km from Earth, it turned in its course to face the Sun for a planned 96 hours in total.

Why does it need to do this? Mauricio Portaluppi – an ESA contamination control engineer, who has been at the launch site supporting cleanliness and contamination control of the satelllite before its launch – explains: “Euclid needs boil away any moisture that potentially might have ended up freezing on its telescope mirrors, obscuring its otherwise pristine views of the distant cosmos beyond our own Milky Way galaxy”.

Euclid’s payload module is passively cooled down to cryogenic temperatures, so any water vapour outgassed from onboard materials such as the multi-layer insulation covering the spacecraft might condense on detectors and mirrors.

“This was more than a purely theoretical concern, because a previous ESA astronomy mission, the 2013-launched Gaia mission to map the Milky Way, also had to deal with the problem of water ice on its optics early in the mission,” explains Bruno Bras, an ESA contamination control expert who also worked on the Gaia project.

“The Materials and Electrical Components Laboratory here at ESA’s ESTEC technical centre worked diligently to recreate this problem on the ground so we could fully model it. This in turn allowed the characterisation of the readings measured in orbit and supported the Gaia spacecraft team in evaluating potential decontamination options and their associated risks. In fact the Lab team ended up winning an ESA Team Excellence Award for our support to Gaia.”

Szilvia Szmolka, ESA materials test engineer, adds: “In the case of Euclid, another cryogenic astronomy mission with a similar flight profile, the aim was to get ahead of the risk in advance. Working in collaboration with the Euclid team and the wider Euclid science consortium we used representative mirror samples in our Yuta vacuum facility to predict the effects of the ice on the Euclid telescope’s optical path, and to see how much heating would be needed to clear this contamination.”

The Lab’s test campaign also amassed a extensive spectral performance database for ice contamination, right down to a single nanometre – or millionth of a millimetre – of thickness, which can be used to support future missions as well.

Credits: ESA

The crew of Soyuz MS-13 farewell friends, family and well-wishers as they board the bus that will take them from the Cosmonaut Hotel to Baikonur cosmodrome in Kazakhstan.

ESA astronaut Luca Parmitano, NASA astronaut Drew Morgan and Roscosmos cosmonaut and Soyuz commander Alexander Skvortsov will be launched in their Soyuz MS-13 spacecraft from the Baikonur Cosmodrome on Saturday 20 July. This date coincides with the 50th anniversary of the Apollo 11 Moon landing and marks the start of Luca’s second space mission known as ‘Beyond’.

While in orbit, Luca will support over 50 European experiments and more than 200 international experiments. He is also expected to perform a number of spacewalks to repair the cooling systems of dark matter hunter, AMS-02.

More information about Luca’s Beyond mission is available on the blog. This will be updated throughout his mission, with updates also shared on Twitter via @esaspaceflight.

Credits: ESA - S. Corvaja

Nothing is entirely immune to the harsh environment of space. Out there, things and organisms degrade at a faster pace and in different ways. To understand how materials age beyond Earth’s atmosphere, up to 141 samples are spending a minimum of six months exposed to outer space for the Euro Material Ageing experiment.

Radiation, vacuum, temperature extremes and even space debris are hitting this selection of inorganic materials on Bartolomeo, Europe’s ‘front porch’ on the International Space Station.

No filters or protection allowed, each sample has a bare surface of 20 millimetres cramped between two aluminium plates. The diverse palette in this image shows metallic glass, ceramic composites, silicon, diamond-like carbon, carbon fibres and plastics, among others.

Europe has years of experience in sending biology samples to space, but this is the first time ESA and the French space agency CNES expose inorganic materials outside the Space Station.

NASA astronauts Sunita Williams and Nick Hague used the Station’s 17-metre-long robotic arm last December to place the Nanoracks airlock on Bartolomeo, where the experiment is facing the full spectrum of space environment hazards.

As Nick Hague said in a social media post, “Materials research is critical to our exploration of space. Vacuum, extreme hot and cold, radiation – these are the harsh realities of the space environment. The right materials can help us survive in space and dare to go further, and can also improve life on Earth!”

Euro Material Ageing is testing how exposure to space can be bad for the health of spacecraft components. Whether a mission is orbiting Earth or operates in deep space, unwanted effects include discoloration, embrittlement and buckling.

The Space Station experiences frequent changes from sunlight to darkness while circling our planet. Materials go through drastic temperature shifts from up to 150°C in sunlight down to –150°C in the shade. Such thermal stresses lead to accelerated ageing, potential cracking and misalignment.

Samples are exposed to highly reactive atomic oxygen formed at the topmost fringes of the atmosphere and known to eat away satellite surfaces. Materials in this experiment will also cope with ‘outgassing’ in vacuum – the gradual boiling away of chemicals and solvents – which could contaminate sensitive satellite surfaces such as lenses.

Results from the Euro Material Ageing experiment could inform the design of fire-retardant and rust-resistant materials, and better protection for satellites could in turn help improve plastic siding for your house.

The exposure time is planned between six and 18 months. After completion, the facility will be transferred back inside the International Space Station. A new set of samples will be waiting for a second immersion into the harshness of space.

Credits: ESA/NASA

This Picture of the Week features the barred spiral galaxy NGC 3059, which lies about 57 million light-years from Earth. The data used to compose this image were collected by Hubble in May 2024, as part of an observing programme that studied a number of galaxies. All the observations were made using the same range of filters: partially transparent materials that allow only very specific wavelengths of light to pass through.

Filters are used extensively in observational astronomy, and can be calibrated to allow either extremely narrow or somewhat broader ranges of light through. Narrow-band filters are invaluable from a scientific perspective because certain light wavelengths are associated with specific physical and chemical processes. For example, under particular conditions, hydrogen atoms are known to emit red light with wavelength value of 656.46 nanometres. Red light at this wavelength is known as H-alpha emission, or the ‘H-alpha line’. It is very useful to astronomers because its presence acts as an indicator of certain physical processes and conditions; it is often a tell-tale sign of new stars being formed, for example.

Thus, narrow-band filters calibrated to allow H-alpha emission through can be used to identify regions of space where stars are forming.

Such a filter was used for this image, the narrow-band filter called F657N or the H-alpha filter. The F stands for filter, and the N stands for narrow. The numerical value refers to the peak wavelength (in nanometres) that the filter lets through. The eagle-eyed amongst you may have noticed that 657 is very close to the 656.46 H-alpha line’s wavelength. Data collected using five other filters contributed to this image as well, all of which were wide-band filters; meaning that they allow a wider range of light wavelengths through. This is less useful for identifying extremely specific lines (such as the H-alpha line) but still enables astronomers to explore relatively specific parts of the electromagnetic spectrum. In addition, collectively the information from multiple filters can be used to make beautiful images such as this one.

[Image Description: A spiral galaxy seen face-on, so that its many arms and its glowing, bar-shaped core can be easily seen. The arms are filled with bluish patches of older stars, pink patches where new stars are forming, and dark threads of dust. A few bright stars with cross-shaped diffraction spikes lie in the foreground.]

Credits: ESA/Hubble & NASA, D. Thilker; CC BY 4.0

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Image description: Flashes on the Moon.

Every few hours, brilliant flashes of light can be seen through a telescope across the lunar surface. It is the result of a meteorite striking our rocky neighbour at great speed.

These impact flashes are called transient lunar phenomena.

The European Space Agency monitors space debris and lunar flashes using ground stations on Earth.

#ForwardToTheMoon

Credits: ESA

The JANUS camera onboard ESA’s Jupiter Icy Moons Explorer (Juice) is designed to take detailed, high-resolution photos of Jupiter and its icy moons.

JANUS will study global, regional and local features and processes on the moons, as well as map the clouds of Jupiter. It will have a resolution up to 2.4 m on Ganymede and about 10 km at Jupiter.

This image of our own Moon was taken during Juice’s lunar-Earth flyby on 19 August 2024. The main aim of JANUS’s observations during the lunar-Earth flyby was to evaluate how well the instrument is performing, not to make scientific measurements.

Find out more

Credits: ESA/Juice/JANUS; CC BY-SA 3.0 IGO

The foreground galaxy whose gravity is bending the light from more distant objects is seen as it was when the Universe was 6.4 billion years old. The more distant lensed galaxy, which appears as an arc, was invisible in previous NASA/ESA Hubble Space Telescope observations and has now been revealed by Webb’s sensitive infrared eyes. This discovery is crucial for studying star formation in distant galaxies.

This gravitational lens is one of eight featured in the September 2025 Picture of the Month.

[Image Description: This image shows a deep galaxy field as seen by Webb, with a distinct gravitational lens at the centre. A central glowing galaxy in the foreground has a warped galaxy from the background curving around its top-left side as an orange arc.]

Credits: ESA/Webb, NASA & CSA, G. Gozaliasl, A. Koekemoer, M. Franco; CC BY 4.0

The performance of a lower limb prostheses has been tested in microgravity conditions for the first time during the latest ESA parabolic flight campaign on the ‘Zero G’ aircraft.

The 86th ESA parabolic flight campaign took off on 21 May 2025 from Bordeaux, France.

Parabolic flights create short windows of microgravity by flying an aircraft in a curved trajectory called a parabola. During each of the 31 parabolas per flight, John and the team experienced 22 seconds of weightlessness, simulating the conditions on the International Space Station.

Credits: ESA/Novespace

ESA's star-surveying Gaia mission has released a treasure trove of new data as part of its ‘focused product release’. As part of this data release Gaia explored Omega Centauri, the largest globular cluster that can be seen from Earth and a great example of a ‘typical’ cluster.

The team has revealed 526 587 stars that Gaia had not seen before, detecting stars that lie too close together to be measured in the telescope’s regular pipeline and those in the cluster core that are up to 15 times fainter than previously seen. The new data reveal 10 times more stars in Omega Centauri; this new knowledge will enable researchers to study the cluster’s structure, how the constituent stars are distributed, how they’re moving, and more.

This image is from Gaia’s Data Release 3 in 2022. It is contrasted in a new slider with an image from today’s data release, to highlight just how many new sources have been imaged in the cluster’s centre. Only faint stars within Omega Centauri are plotted here.

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Alt-text: This image shows a star cluster, which appears as a collection of bright stars against a dark background. The roughly circular cluster appears like a doughnut with an empty centre.

Acknowledgments: Michele Trabucchi, Nami Mowlavi and Thomas Lebzelter

Credits: ESA/Gaia/DPAC, CC BY-SA 3.0 IGO

The third Copernicus Sentinel-2 satellite, Sentinel-2C, has launched aboard the final Vega rocket, flight VV24, from Europe’s Spaceport in French Guiana. The rocket lifted off on 5 September at 03:50 CEST (4 September 22:50 local time).

Sentinel-2C will provide high-resolution data that is essential to Copernicus – the Earth observation component of the European Union’s Space programme. Developed, built and operated by ESA, the Copernicus Sentinel-2 mission provides high-resolution optical imagery for a wide range of applications including land, water and atmospheric monitoring.

The mission is based on a constellation of two identical satellites flying in the same orbit but 180° apart: Sentinel-2A and Sentinel-2B. Together, they cover all of Earth’s land and coastal waters every five days. Once Sentinel-2C is operational, it will replace its predecessor, Sentinel-2A, following a brief period of tandem observations. Sentinel-2D will eventually take over from Sentinel-2B.

Sentinel-2C was the last liftoff for the Vega rocket. After 12 years of service, Vega is being retired to make way for the upgraded Vega-C rocket.

Credits: ESA–S. Corvaja

This image covers a portion of the wall-terrace region of the 100 km-wide Columbus Crater located within Terra Sirenum in the southern hemisphere of Mars. The image was taken by the Colour and Stereo Surface Imaging System (CaSSIS) onboard the ESA-Roscosmos ExoMars Trace Gas Orbiter on 15 January 2019.

Layered rocks that appear in light-tones are found extensively on the northern crater walls, terraces and floor. These rocks have subsequently been eroded to expose successive layers in cross-section.

The CRISM spectrometer onboard NASA’s Mars Reconnaissance Orbiter has already revealed that these layers contain various hydrated minerals, such as sulphate salts that appear to cover the white-coloured rocks. The beige-coloured layered rocks, consistent with a sulphate salt signature, appear to line the crater wall, reminiscent of a high water mark.

These ‘bathtub rings’ are consistent with deposits formed by lakes that start to dry up and, through evaporation, begin to deposit specific minerals turn by turn. As the water evaporates, the minerals that are the least readily dissolved in water will begin to precipitate out of the dwindling solution.

The relatively small 1.6 km-wide impact crater towards the top of the image appears to have a small amount of white-coloured bedrock exposed in its wall, which CRISM indicates is aluminous clay-bearing material. This suggests that the clay-bearing rocks are older than the sulphate salts that occupy the central portion of this image section.

Sites like these could have once offered conditions suitable for life.

The image is centred at 28.79ºS/193.84ºE. North is up.

Credits: ESA/Roscosmos/CaSSIS, CC BY-SA 3.0 IGO

Over one-third of the ‘normal’ matter in the local Universe – the visible stuff making up stars, planets, galaxies, life – is missing. It hasn’t yet been seen, but it’s needed to make our models of the cosmos work properly.

Said models suggest that this elusive matter might exist in long strings of gas, or filaments, bridging the densest pockets of space. While we’ve spotted filaments before, it’s tricky to make out their properties; they’re typically faint, making it difficult to isolate their light from that of any galaxies, black holes, and other objects lying nearby.

New research is now one ofthe first to do just this, finding and accurately characterising a single filament of hot gas stretching between four clusters of galaxies in the nearby Universe. The astronomers used ESA’s XMM-Newton and JAXA’s Suzaku X-ray space telescope to make the discovery.

This image shows the new filament, which connects four galaxy clusters: two on one end, two on the other. These clusters are visible as bright spots at the bottom and top of the filament (four white dots encircled by colour). A mottled band of purple stretches between these bright dots, standing out brightly against the black surrounding sky; this is the filament of X-ray-emitting hot gas that had not been seen before, and contains a chunk of ‘missing’ matter.

The purple band comprises data from Suzaku. The astronomers were able to identify and remove any possible ‘contaminating’ sources of X-rays from the filament using XMM-Newton, leaving behind a pure thread of ‘missing’ matter. These sources can be seen here as bright dots studded through – and removed from – the filament’s emission.

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[Image description: The image shows a cluster of bright, colourful spots against a black background. The spots are primarily purple with areas of intense brightness in the centre, transitioning from yellow to green and blue. These spots are connected by a faint purple structure, forming an irregular extended shape with hazy blobs at either end.]

CREDIT

ESA/XMM-Newton and ISAS/JAXA

ACKNOWLEDGEMENTS

Migkas et al. (2025), ATG Europe; CC BY-SA 3.0 IGO