ESO Top News
Week in images: 30 June - 4 July 2025
Week in images: 30 June - 4 July 2025
Discover our week through the lens
Earth from Space: Zanzibar, Tanzania
Antarctic waters getting saltier as sea ice wanes
Using data from ESA’s SMOS satellite, scientists have revealed a surprising shift in the Southern Ocean – surface waters around Antarctica are growing saltier, even as sea ice is diminishing rapidly. This finding defies the norm because melting ice typically freshens ocean surface water.
The implications are far-reaching as changes in this remote region can disrupt global ocean currents, affect climate patterns, and alter ecosystems far beyond the Antarctic.
ESA tracks rare interstellar comet
Astronomers have confirmed the discovery of a rare celestial visitor: a comet from beyond our Solar System.
Officially named 3I/ATLAS, this newly identified interstellar object is only the third of its kind ever observed, following the famous 1I/ʻOumuamua in 2017 and 2I/Borisov in 2019.
Clingy planets can trigger own doom, suspect Cheops and TESS
Astronomers using the European Space Agency’s Cheops mission have caught an exoplanet that seems to be triggering flares of radiation from the star it orbits. These tremendous explosions are blasting away the planet’s wispy atmosphere, causing it to shrink every year.
This is the first-ever evidence for a ‘planet with a death wish’. Though it was theorised to be possible since the nineties, the flares seen in this research are around 100 times more energetic than expected.
MTG-S1 and Copernicus Sentinel-4 mission highlights
Two meteorological missions – Meteosat Third Generation Sounder-1 (MTG-S1) and the Copernicus Sentinel-4 mission – have launched on board a SpaceX Falcon 9 from Cape Canaveral in Florida, US.
Both are world-class Earth observation missions developed with European partners to address scientific and societal challenges.
The MTG-S1 satellite will generate a completely new type of data product, especially suited to nowcasting severe weather events, with three-dimensional views of the atmosphere. It is the second in the MTG constellation to be prepared for orbit and is equipped with the first European operational Infrared Sounder instrument.
Copernicus Sentinel-4 will be the first mission to monitor European air quality from geostationary orbit, providing hourly information that will transform how we predict air pollution across Europe, using its ultraviolet, visible, near-infrared light (UVN) spectrometer.
MTG-S1 and Copernicus Sentinel-4 launch highlights
Two meteorological missions – Meteosat Third Generation Sounder-1 (MTG-S1) and the Copernicus Sentinel-4 mission – have launched on board a SpaceX Falcon 9 from Cape Canaveral in Florida, US.
Both are world-class Earth observation missions developed with European partners to address scientific and societal challenges.
The MTG-S1 satellite will generate a completely new type of data product, especially suited to nowcasting severe weather events, with three-dimensional views of the atmosphere. It is the second in the MTG constellation to be prepared for orbit and is equipped with the first European operational Infrared Sounder instrument.
Copernicus Sentinel-4 will be the first mission to monitor European air quality from geostationary orbit, providing hourly information that will transform how we predict air pollution across Europe, using its ultraviolet, visible, near-infrared light (UVN) spectrometer.
MTG-S1 and Sentinel-4 launch to change how we see our atmosphere
The second of the Meteosat Third Generation (MTG) satellites and the first instrument for the Copernicus Sentinel-4 mission lifted off at 23:04 CEST on Tuesday, 1 July. The satellite is now on its way to monitor Earth’s atmosphere from an altitude of 36 000 km. From this geostationary orbit, the missions can provide game-changing data for forecasting severe storms and air pollution over Europe.
Southern Europe’s land and sea sizzles
A pinch of France in space
ESA astronaut Sophie Adenot selected the French chef Anne-Sophie Pic to develop the bonus food she will bring to the International Space Station during her mission εpsilon.
MTG-S1 satellite hosting the Sentinel-4 instrument is ready for liftoff
The Meteosat Third Generation Sounder (MTG-S1) satellite, which is hosting the instrument for the Copernicus Sentinel-4 mission, has been placed inside the nose cone of the Falcon 9 launch rocket and is ready for the scheduled liftoff at 23:03 CEST on Tuesday, 1 July.
Plato’s eyes meet brain
On 11 June, engineers at OHB’s facilities in Germany joined together the two main parts of ESA’s Plato mission.
They used a special crane to lift Plato’s payload module, housing its 26 ultra-sensitive cameras, into the air and carefully line it up over the service module. The supporting service module contains everything else that the spacecraft needs to function, including subsystems for power, propulsion and communication with Earth.
With millimetre-level precision, the engineers gently lowered the payload module into place. Once perfectly positioned, the team tested the electrical connections.
Finally, they securely closed a panel that connects the payload module to the service module both physically and electronically (seen ‘hanging’ horizontally above the service module in this image). This panel, which opens and closes with hinges, also contains the electronics to process data from the cameras.
Now in one piece, Plato is one step closer to beginning its hunt for Earth-like planets.
In the coming weeks, the spacecraft will undergo tests to ensure its cameras and data processing systems still work perfectly.
Then it will be driven from OHB’s cleanrooms to ESA’s technical heart (ESTEC) in the Netherlands. At ESTEC, engineers will complete the spacecraft by fitting it with a combined sunshield and solar panel module.
Following a series of essential tests to confirm that Plato is fit for launch and ready to work in space, it will be shipped to Europe’s launch site in French Guiana.
The mission is scheduled to launch on an Ariane 6 in December 2026.
Access the related broadcast quality video footage.
ESA’s Plato (PLAnetary Transits and Oscillations of stars) will use 26 cameras to study terrestrial exoplanets in orbits up to the habitable zone of Sun-like stars.
Plato's scientific instrumentation, consisting of the cameras and electronic units, is provided through a collaboration between ESA and the Plato Mission Consortium. This Consortium is composed of various European research centres, institutes and industries, led by the German Aerospace Center (DLR). The spacecraft is being built and assembled by the industrial Plato Core Team led by OHB together with Thales Alenia Space and Beyond Gravity.
Webb spots a starburst shining in infrared
A new adventure on the International Space Station
Daniel Neuenschwander, ESA head of Space and Robotic Exploration, explains that Ignis mission will include an ambitious technological and scientific programme with several experiments led by ESA and proposed by the Polish space industry.
On 26 June 2025, ESA project astronaut Sławosz Uznański-Wiśniewski from Poland and his crewmates arrived to the International Space Station on the Axiom-4 mission (Ax-4).
The Polish project astronaut is the second of a new generation of European astronauts to fly on a commercial human spaceflight opportunity with Axiom Space.
Week in images: 23-27 June 2025
Week in images: 23-27 June 2025
Discover our week through the lens
Will asteroid 2024 YR4 hit the Moon?
Asteroid 2024 YR4 made headlines earlier this year when its probability of impacting Earth in 2032 rose as high as 3%. While an Earth impact has now been ruled out, the asteroid’s story continues.
The final glimpse of the asteroid as it faded out of view of humankind’s most powerful telescopes left it with a 4% chance of colliding with the Moon on 22 December 2032.
The likelihood of a lunar impact will now remain stable until the asteroid returns to view in mid-2028. In this FAQ, find out why we are left with this lingering uncertainty and how ESA's planned NEOMIR space telescope will help us avoid similar situations in the future.
Ax-4 joins the International Space Station
On 26 June 2025 ESA project astronaut Sławosz Uznański-Wiśniewski from Poland and his crewmates arrived to the International Space Station on the Axiom-4 mission (Ax-4).
The Polish project astronaut is the second of a new generation of European astronauts to fly on a commercial human spaceflight opportunity with Axiom Space.
Sponsored by the Polish government and supported by ESA, the Polish Ministry of Economic Development and Technology (MRiT), and the Polish Space Agency (POLSA), the mission will include an ambitious technological and scientific programme with several experiments led by ESA and proposed by the Polish space industry.
Access the related broadcast quality footage: Launch campaign / Training
New ESA gravity mission to detect weakening ocean conveyor
At the Living Planet Symposium, attendees have been hearing how ESA’s Next Generation Gravity Mission could provide the first opportunity to directly track a vital ocean circulation system that warms our planet – but is now weakening, risking a possible collapse with far-reaching consequences.
Watch MTG-S1 and Sentinel-4 launch live
The second of the Meteosat Third Generation (MTG) satellites and the first instrument for the Copernicus Sentinel-4 mission are ready for liftoff at Cape Canaveral in Florida, US. Live coverage of this launch will be shown on ESA WebTV, on Tuesday, 1 July.
Earth tones on Mars
The European Space Agency’s Mars Express has captured a swirl of colour on the Red Planet, with yellows and rust-oranges meeting deep reds and browns. Lurking within this martian palette are not one but four dust devils, each snaking their way across the surface.