European Space Agency

Image: Aeolus control team wraps up successful reentry operations View the full article

Week in images: 24-28 July 2023 Discover our week through the lens View the full article

Video: 00:01:47 In the month after its launch on 1 July, Euclid has travelled 1.5 million kilometres from Earth towards the Sun-Earth Lagrange point L2, meaning it has ‘arrived’ at its destination orbit. This animation showcases the orbits of Euclid (green), the James Webb Space Telescope (blue), and the Gaia mission (yellow) around this unique position in space. The positions of the spacecraft in this animation don’t correspond to their current positions in space. Located about 1.5 million kilometres from Earth in the opposite direction from the Sun, L2 is about four times further away than our Moon. Several other space missions like Webb and Gaia also orbit L2 as it offers the perfect vantage point to study the Universe. At L2, the spacecraft can keep the Sun, Earth and Moon behind them at all times, so they don’t interfere with observations, while at the same time getting a clear view of deep space and pointing an antenna back to Earth to remain in close communication. Euclid and Webb’s halo orbit around L2 is big. In terms of distance, the ‘radius’ of Euclid’s orbit varies from about 400 000 kilometres at its closest to the centre, and up to 800 000 kilometres at its furthest. By the time Euclid has completed one full revolution around L2, the Moon will have circled the Earth six times. Gaia orbits L2 in a Lissajous orbit, with a maximum distance of around 350 000 km from its centre. The region around L2 is big and even though the orbits of these spacecraft seem to cross in the animation, in reality there is plenty of space and a collision can be easily avoided. For example, Webb and Gaia are between 400 000 and 1 100 000 km apart, depending on where they are in their respective orbits. View the full article

Image: The Copernicus Sentinel-1 mission takes us over the Río de la Plata estuary between Argentina and Uruguay. View the full article

Image: Astronaut Andreas Mogensen undergoing VR training for EVA emergencies View the full article

When astronauts return to the Moon they will be bringing along a new generation of spacesuits, designed to withstand the harsh conditions of the lunar surface. But in keeping their human occupants safe and comfortable, these suits might also become a fertile environment for harmful microbial life – especially as astronauts will potentially be sharing suits with one another. View the full article

Aeolus reentry - LIVE Get rolling updates on the Aeolus reentry, on the Rocket Science blog View the full article

Video: 00:46:24 On Tuesday 25 July, the four crew members of Crew-7, Jasmin Moghbeli (NASA), Andreas Mogensen (ESA), Satoshi Furukawa (JAXA) and Konstantin Borisov (Roscosmos) hosted a news conference where they talk about their upcoming mission to the International Space Station. View the full article

Image: Webb snaps detailed infrared image of actively forming stars View the full article

Video: 00:02:42 After a remarkable life in orbit, Aeolus is out of fuel and out of time – it’s returning to Earth this week. Planned and built before any regulations were put in place on ‘end-of-life’ disposal, the Earth Explorer was designed to naturally return through our atmosphere. After months of detailed planning and analysis, ESA together with industrial partners has designed a complex and never-before-performed set of manoeuvres to control, as much as possible, Aeolus’ fall. The assisted reentry attempt is built on four main phases, now begun at ESA’s mission control: Phase I: once Aeolus has fallen naturally to 280 km, the first manoeuvre is performed – the largest in the mission’s five years in orbit. The main objectives are to lower the satellite down to 250 km and to check how the satellite behaves when executing a large manoeuvre at such low altitudes – more than three times the size of any performed during routine operations. Phase II: after three to five days, a series of four manoeuvres will lower Aeolus’s ‘perigee altitude’ – the point in orbit closest to Earth – down to an altitude of about 150 km. Phase III: a final manoeuvre will lower [LJ1] Aeolus to a perigee altitude of 120 km. Phase IV: in the final, shortest phase, Aeolus the spacecraft becomes space debris, completing its final descent in just a few Earth revolutions. In this animation, round regions temporarily lit up in bright green show the moments that Aeolus is in contact with antennas on Earth. It is in these periods that mission control is in touch with the satellite and can send up commands and get its data down. Aeolus is repeatedly turned, or ‘slewed’ by 180° in order to switch from the routine orientation (or ‘attitude’), in which the satellite’s ‘X-band’ antenna points toward Earth and the GPS can function to track the mission – crucial to maintaining knowledge of its position – and the ‘retrograde’ attitude. This second, ‘upside down’ position is necessary for the thrusters to fire in the opposite direction to Aeolus’s flight direction, causing it to lose energy and lower in orbit. While the ultimate goal is for the spacecraft to burn up as it reenters through the atmosphere, teams need to keep it functioning long enough that they can continue to send up commands and control it on its path. After the final commands are sent, Aeolus will be ‘passivated’. Passivation is when any energy onboard a spacecraft is removed, for example, its propellant or batteries. Doing this prevents explosions and fragmentation events, that could cause the release of lots of pieces of unwanted space debris. For Aeolus, already out of fuel, it will simply be turned off. After this point, teams at mission control will continue to monitor the situation until Aeolus’s ultimate reentry location is confirmed. For rolling updates on Aeolus's reentry, follow ‘Aeolus reentry: live’ on the Rocket Science blog. Music: Yesterday’s Hero by Steve Rothery, published by Tunecore. Used with permission of Steve Rothery. View the full article

On 10 July 2023, a volcano some 30 km from Iceland’s capital, Reykjavik, erupted following heightened seismic activity in the area. Satellites orbiting above us have captured the molten lava and smoke plume puffing from the Litli-Hrútur volcano. View the full article

Astronaut Frank Rubio aboard the International Space Station collaborated with a small team of robots on Earth to accomplish a complex task – a first test of a new approach to combine human and robotic capabilities for our return to the Moon and beyond. View the full article

Satellites will soon be used to keep an independent eye on airborne planes, under a deal agreed between ESA and Spire Global, a company that provides space-based data, analytics and space services. View the full article

Globally, more than 70% of the freshwater withdrawn from Earth’s surface or from underground is used to irrigate crops. The need to produce more food for a growing population against the backdrop of climate change is challenging enough, but satellites reveal that extracting water doesn’t just affect the local environment – there are knock-on consequences for many aspects of the Earth system. View the full article

Teams preparing Ariane 6 for its inaugural flight successfully completed for the first time a launcher preparation and countdown sequence, on 18 July at Europe’s Spaceport in Kourou, French Guiana. View the full article

New measurements by the NASA/ESA/CSA James Webb Space Telescope’s Mid-InfraRed Instrument (MIRI) has detected water vapour in the inner disc of the system PDS 70, located 370 light-years away. This is the first detection of water in the terrestrial region of a disc already known to host two or more protoplanets. View the full article

Image: Rhodes wildfire forces thousands to flee View the full article

Image: New Galileo station goes on duty View the full article

Week in images: 17-21 July 2023 Discover our week through the lens View the full article

Video: 00:05:00 ESA’s wind mission Aeolus is coming home. After five years of improving weather forecasts, the satellite will return in a first-of-its-kind assisted reentry. At ESA’s Space Operations Centre in Germany, mission control will use the satellite’s remaining fuel to steer Aeolus during its return to Earth. Find out more about the mission, its successes and how Aeolus is paving the way for safe reentries. View the full article

Image: This Copernicus Sentinel-2 image highlights the colours of autumn over the southern part of New York state in the US. View the full article

Astronomers using the NASA/ESA/ Hubble Space Telescope’s extraordinary sensitivity have discovered a swarm of boulders that were possibly shaken off the asteroid Dimorphos when NASA deliberately slammed the half-tonne DART impactor spacecraft into Dimorphos at approximately 22 500 kilometres per hour. DART intentionally impacted Dimorphos on 26 September 2022, slightly changing the trajectory of its orbit around the larger asteroid Didymos. View the full article

Image: 3D-printed bend-based mechanism View the full article

The Italian region of Emilia-Romagna was devastated by severe floods in May 2023, claiming lives and displacing thousands of people, resulting in an estimated €8.8 billion in damages. With the region still grappling with the aftermath, satellites have been instrumental in assessing the damages of the affected areas. View the full article

Image: Dividing Earth and Moon View the full article