Aerospace

Only the most sensitive detectors in the world can pick up gravitational waves – ripples in the fabric of spacetime caused by objects accelerating through the universe. The GraWIToN Initial Training Network was training 13 early-career researchers in the field just as a new generation of detectors in Europe and the United States were recording the first ever gravitational wave signals, which came from two black holes colliding with each other and another colliding pair of neutron stars. As a result, some of the young scientists had the opportunity to participate in this ground-breaking discovery, which was awarded a Nobel Prize in 2017. The GraWIToN project meant that a new generation of European researchers is perfectly placed to push forward the development of the Einstein Telescope, a planned European ground-based gravitational-wave observatory which will be at least 10 times more sensitive than current detectors. The scientists who participated in GraWIToN are also helping to shape the development of the ESA/NASA LISA mission to put the first ever gravitational wave detector into space.

Understanding how planets were formed and evolve is a complex task. One of the biggest clues lies in a planet’s magnetic field. A planet’s magnetic field helps to reveal its structure, composition, and core temperature, all key clues to its geological history. The PETRA project used spacecraft and laboratory measurements to examine this planetary history. The methodologies developed by the lead researcher, Dr. Foteini Vervelidou, can maximise the scientific benefits of space missions (e.g., the mission to planet Mercury, BepiColombo, and the program to send humans back to the Moon, Artemis). Another key aspect of the project was to build European expertise in measuring magnetic properties of materials at small scales, known as magnetic microscopy. As part of the project, Foteini studied Moon rock samples collected from the Apollo 17 mission. Her studies showed that the Moon’s magnetic field dropped over time, possibly reaching zero around 1.7 billion years ago. Foteini also developed a protocol to determine if a sample had been remagnetised, after discovering that a Martian meteorite with 4.4 billion-year-old crystals had been exposed to strong hand magnets, which destroyed its magnetic history.

Why was a planet not engulfed as its star entered its red giant phase? As part of the PULSATION project, Dr. Tiago Campante answered this question using the emerging field of asteroseismology, which studies how sound waves move through stars. By listening to the natural oscillations of stars, asteroseismologists are able to work out their mass, radius and age with unprecedented precision, transforming how they understand the planets that orbit them. Using data from NASA’s planet-hunting TESS mission, Tiago surveyed around 100 000 late-stage stars, combining asteroseismology with transit photometry – the dimming of light as a planet passes in front of its star. This enabled him to propose that tidal interactions between the planet and its sun may have led to its survival, and to contribute to the discovery of two new Saturn-like planets. The project also conducted an outreach programme in partnership with Ciência Viva, a network of science centres across Portugal, engaging citizens and demonstrating how European-funded space research can inspire communities.