ESO Top News

Watch the replay of the media information session in which ESA Director General Josef Aschbacher and ESA Council Chair Renato Krpoun (CH) update journalists on key decisions taken at the ESA Council meeting, held at ESA Headquarters in Paris on 17 and 18 December 2025.

It has been a busy year for the European Space Agency’s Proba-3 mission. The satellite duo has already created more than 50 artificial solar eclipses in orbit since the mission operations began less than a year ago. The resulting data confirm Proba-3's ability to provide the missing puzzle piece in our observations of the Sun's enigmatic atmosphere – the corona.

On 17 December, two Galileo satellites lifted off from Europe’s Spaceport in French Guiana aboard an Ariane 6 rocket. This marked the 14th launch for Europe’s Galileo constellation, reinforcing Europe’s satellite navigation capabilities, resilience and autonomy. 

On 17 December, two new Galileo satellites lifted off from Europe’s Spaceport in French Guiana aboard an Ariane 6 rocket. This marked the 14th launch for Europe’s satellite navigation operational satellite programme, reinforcing Europe’s resilience and autonomy.

The European Space Agency (ESA) is responsible for carrying out the Galileo launch with Arianespace on behalf of the European Commission. The Galileo satellites were manufactured by OHB, under contract with ESA. Once in orbit, the EU Agency for the Space Programme (EUSPA) will bring the satellites into service and oversee their operation.

The flight, designated VA266, was the first launch of Galileo satellites on Europe’s newest heavy-lift launcher Ariane 6.

Follow the launch campaign. 

Access the related broadcast quality video material. 

Copernicus Sentinel-6B, launched last month, has reached its orbit and delivered its first set of data, which show variations in sea level in the North Atlantic Ocean. This data underlines how the mission will continue to strengthen the long-term reference record of sea levels, a key parameter of climate change.

2025 was a landmark year for Europe in space. From celebrating 50 years of ESA to new missions, scientific breakthroughs, the year reaffirmed Europe’s leadership in science, exploration, climate action and innovation.

Ever wondered how planetary systems like our own Solar System form? Thanks to the European Space Agency’s Gaia space telescope, we're getting a unique peek behind the cosmic curtain into these dusty environments.

In this collage, we see the images of 31 baby star systems. Click on the white dots next to each system to find out more about them. The bar on the top right shows the scale of the image in Astronomical Units (AU).

The collage also shows our own Solar System for reference on the bottom right, as it is predicted to have looked at an age of 1 million years, with the Sun at its centre (not visible).

All of the systems are centred around very young stars that have recently collapsed from vast clouds of gas and dust.

After the clouds collapsed under their own gravity, they spun faster and flattened into discs with hot, dense centres. These centres became the stars, sometimes multiple stars were formed. The discs around them are called protoplanetary discs.

The 31 baby systems are shown here in orange-purple, as seen by the Atacama Large Millimeter Array (ALMA) ground-based telescope.

Astronomers expect the remaining material in protoplanetary discs to clump together to form planets, but until now it’s been very difficult to spot them because of all the dust and gas present in discs. To date, very few planets have been detected around forming stars.

Enter Gaia.

In 31 out of 98 young star systems, Gaia has detected subtle motions that suggest the presence of unseen companions. For seven of these systems, the observed motions are consistent with objects of planetary mass. In eight systems, the data best match the presence of brown dwarfs – objects larger than planets but smaller than stars. The remaining sixteen systems likely have additional stars around.

Gaia’s predicted locations of these companions in the systems are shown in cyan. In the reference image of our baby Solar System, Jupiter’s orbit is also shown in cyan.

Gaia discovered the companions in the baby star systems thanks to its unique ability to sense the gravitational tug or ‘wobble’ a planet or companion induces on a star. This technique had already been used to find companions around older stars. But now, for the first time, a team of astronomers led by Miguel Vioque of the European Southern Observatory, Germany, has used this Gaia technique to find planets and companions around stars that are still forming.

The all-sky, large-scale nature of the Gaia survey enabled the team to study hundreds of forming stars and identify companions across large samples for the first time. This in contrast to costly ground-based searches that can only target a few stars at a time.

This ability of Gaia is revolutionising the field of star and planet formation. The companions that the telescope has already found, can now be followed up by telescopes like the NASA/ESA/CSA James Webb Space telescope that can study the inner discs of the baby systems in more detail.

With Gaia’s upcoming fourth data release, many more hidden planets are expected to be uncovered.

This new finding has been described in ‘Astrometric view of companions in the inner dust cavities of protoplanetary disks’ by M. Vioque et al., accepted for publication in Astronomy & Astrophysics. 

Learn more

[Image description: A collage of 32 glowing discs on a black background. Each disc shows concentric rings in vivid colours: purple, orange, and yellow, with bright cyan centres. The discs vary in size and orientation, creating a striking pattern of circular and elliptical shapes.]

Satellites are emerging as a powerful new tool in the fight to curb emissions of methane. While methane is much shorter-lived in the atmosphere than carbon dioxide, it is vastly more potent at trapping heat, which makes rapid cuts essential for slowing warming in the short term. The same satellite technology that has transformed methane monitoring in the oil and gas sector is now being turned towards another major source – landfill sites.