Next generation instruments for tomorrow’s space missions
Researchers and engineers of PIONEERS project gathered at ISAE-SUPAERO (Toulouse, France) for the kick-off meeting of the project.
Highly sophisticated instruments are required for the space missions of tomorrow. Researchers in the PIONEERS project are working to develop the next generation of seismic instruments, providing data that will help scientists understand the interior structure of planets and asteroids, as Dr Raphael Garcia explains. next generation of space missions will require highly sophisticated and sensitive seismometers to fulfil their science objectives, with several space agencies looking to investigate the interior structure of planets and asteroids. As a researcher at ISAESUPAERO in Toulouse, Dr Raphael Garcia is part of the PIONEERS project, an initiative working to develop new instruments for space missions. “We are developing two models in the project. One is the Compact Model, which relies on existing technology but requires a qualification for space use. Another is the High-Performance Model, which is a new sensing concept for a seismometer. This relies on optical interferometry and fiber-optic gyroscopes,” he outlines. The Compact Model is designed for application on small bodies, such as asteroids, while the High-Performance Model is intended for gathering seismic information on planets, in particular the Moon and Mars. This work builds on earlier planetary seismology research. “We know that there are quakes on the Moon for example, as some seismic work was done on the Apollo missions,” continues Dr Garcia. “We are not sure about the small bodies. However, we do know that there are high temperature changes on the surface of these bodies, and these will cause small cracks that can be considered as micro-seismicity.”
The H2020 project PIONEERS aims at developing the next generation of planetary seismometers sensing both translation and rotations of the ground. By changing the technology in direction of optical interferometry, the project target both a prototype of a high performance instrument for the Moon and a qualification model of a compact instrument for asteroids.
Project Funding Readiness Level (TRL) by the end of the project, bringing it closer to practical application. “When deployed on the surface, one objective for the model is to monitor the rebound on landing,” says Dr Garcia. “With these rebounds we can monitor the mechanical response of the ground. Once landed, we can monitor the cracks in the asteroid and try to image the asteroid’s internal structure.” The rotation sensors can also record more subtle changes, providing an insight into mass distribution inside an asteroid. This is particularly relevant for binary systems such
Planetary vibrations and rotations targeted by PIONEERS instruments for internal structure imaging.
structure of planets and asteroids. With records of both the translations and rotations generated by seismic waves, researchers can look to separate different types of waves and gain more information about their source. “These kinds of developments are ongoing for Earth’s seismology and demonstrate the interest of such concepts,
PIONEERS project
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Planetary Instruments based on Optical technologies for an iNnovative European Exploration using Rotational Seismology Project Objectives
The
The aim now in the project is to develop more sensitive and less noisy instruments, capable of detecting the propagation of seismic waves on different bodies in the solar system. In the case of the Moon, the instrument needs to have extremely low noise in order to be able to monitor very small variations. “This is because moonquakes are typically small and the noise – such as the background vibrations of the Moon – is low. So we need to design instruments to measure such very low signals,” explains Dr Garcia. “We are developing a high-performance system that is much more sensitive than conventional seismometers.” These instruments under development in the PIONEERS project are designed to provide rotational data in addition to the translational data, which can open up new insights into the
PIONEERS
Different internal models of jupiter icy moons that may be decipher through the deployment of seismometers on their surface.
but neither has been studied for bodies in the solar system. However, we do now have a much deeper understanding of the seismic measurements on Mars thanks to the performance of NASA’s InSight mission,” says Dr Garcia. A seismometer called SEIS was placed on the surface of the red planet as part of the InSight mission, providing data on seismic activity. There remains much to learn about the interior of Mars however, with Dr Garcia and his colleagues working to develop instruments that can provide a clearer picture. “The main source of noise on Mars is the atmosphere which generates ground rotations. Current sensors are not able to differentiate between ground rotations and ground translations,” he outlines. “One application of rotation measurements would be to essentially de-noise the Mars data from the atmospheric perturbation coming from the surface. This would be possible with the our High-Performance Model.” Further applications of the project’s instruments are envisaged, with the Compact Model targeting asteroid-sized bodies like Phobos, a relatively large moon of Mars which is on a collision course with the red planet. This model should be at a relatively high Technology
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identified as potential locations for this work, as Dr Garcia explains. “They have vacuum chambers that are isolated from ground vibrations, which is the kind of test facility that we need,” he outlines. “We have collaborated with external partners to test this high-performance instrument.” The High-Performance Model should be at a TRL of between 3/4 by the end of the project, nearing validation in the laboratory, with the main objective of applying it eventually on the Moon. Missions to the Moon are planned for the coming years, and Dr Garcia says data about its interior structure and meteoroid
Moonquakes are typically small and the background seismic noise is low. So we need to design instruments to measure very low signals. We are developing a highperformance system that is much more sensitive than conventional seismometers. as the asteroid Didymos and its moonlet Dimorphos, which was successfully targeted by NASA’s recent DART mission. “Rotation dynamics are strongly influenced by the mass distribution inside the asteroid. This is relevant for imaging the internal structure and understanding the mechanical properties of the asteroid,” says Dr Garcia. It may be necessary in future to deflect objects on a collision course with our own planet, underlining the wider importance of this research. “We are exploring different ideas on how we can improve the instruments,” continues Dr Garcia.
Instrument validation The PIONEERS instruments also need to be validated, which is done through land-based experiments in the project. This validation process is extremely complex, in particular for the HighPerformance Model. “This is because the noise levels are so low that there are very few places on Earth with comparable levels,” says Dr Garcia. The facilities of the European teams working on the VIRGO gravitational wave detector have been
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impact rates will be highly valuable. Alongside developing and validating the instruments, researchers are also developing tools to analyse the data they generate. “One work package in the project is dedicated to scientific analysis, including data analysis methods and field experiments. The other work packages are focused on building and validating the instruments,” continues Dr Garcia. Terrestrial model of an instrument, commercialized by Exail (formerly iXblue) project partner, which combines translation and rotation measurements.
The PIONEERS project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 821881.
Project Partners
• Institut Supérieur l’Aéronautique et de l’Espace (ISAE-SUPAERO, Toulouse) • E xail (formerly iXblue) (Saint Germain en laye) • Institut de Physique du Globe de Paris (IPGP, CNRS, Université Paris cité – Paris) • Eidgenoessische Technische Hochschule Zuerich (ETH, Zürich) • Ludwig-Maximilians-Universitaet Muenchen(LMU, Muenchen) • Koninklijke Sterrenwacht Van Belgie (ORB, Brussel)
Contact Details
Project Coordinator, Professor Raphael F. Garcia ISAE-SUPAERO / DEOS / SSPA 10, ave E. Belin, 31400 Toulouse, France Office room 07.155 T: +33 561338114 E: raphael.garcia@isae.fr W: https://h2020-pioneers.eu/ W: https://www.webofscience.com/wos/ author/record/B-2612-2012 Professor Raphael F. Garcia
Dr Raphael F. Garcia is Professor at Aeronautics and Space Institute (ISAESUPAERO). He conducts research on internal structure of Moon and Mars relying on seismological data sets, and develops new sensing methods based on solid/atmosphere couplings. He provided estimates of lunar core radius, and demonstrated that seismic waves can be sensed by drag variations of low orbit satellites and by pressure sensors on board stratospheric balloons.
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