LESIA is a lead space laboratory in France involved in the data analysis and archiving of space missions and large telescopes instruments in astrophysics.
The scientific strategy of LESIA derives from its know-how, its skills, and the opportunities of the discipline. As it is dedicated to fundamental research and focused on scientific instrumentation (both ground- and space-based), LESIA follows instrumental projects starting from the definition of the scientific and technical specifications to the exploitation, interpretation, and archiving of data in perennial databases.
Instrumental research is not the primary goal of the laboratory, however, but rather a means towards new scientific advances. Part of LESIA’s scientific activities are also focused on modeling, theory, and simulation: these theoretical activities are synergised with instrumental developments to adapt the technical and scientific specifications in a virtuous iterative process. One example amongst others is, in plasma physics, plasma density/temperature measurements by thermal noise measurements invented in the laboratory and now currently exploited in space missions.
The strong inertia of international organisations for major projects (ELT, space missions) gives the possibility for the long-term structuring of activities. However, the risk of seeing activity curbed by outdated technological choices requires a constant vigilance in R&D activities. In the field of space instrumentation, the ESEP Laboratoire d’Excellence (Exploration Spatiale des Environnements Planétaires) selected by the French initiative ‘Investissements d’Avenir’ is an important element of support for the renewal of instrumentation activities.
The scientific strategy of LESIA is defined in each of its five poles: High Angular Resolution in Astrophysics, Planetology, Stellar Physics, Plasma Physics and Solar Physics. Only a global strategy is described here, as well as the transversal aspects common to several poles. The scientific scope of the laboratory is not limited to its major projects, however, but projects led by small teams also benefit from the ripple effect. The structuring effect of large projects is nevertheless essential for the laboratory, and will be particularly emphasised in this article.
Major projects concern a large part of the laboratory’s FTE involvement and are therefore extremely beneficial for LESIA, both in terms of researchers and engineers. Their duration, which is currently counted in decennials, is also a fundamental part of the laboratory’s strategy, going well beyond a standard five-year contract. Projects already committed to are:
• Bepi Colombo is the ESA/JAXA mission to Mercury, launched on 19 October 2018. The activities of LESIA are present in several instruments: one, SORBET, on the Mercury Magnetospheric Orbiter (JAXA), the other, VIHI, on the Mercury Planetary Orbiter of the dual mission Bepi Colombo. Over the five-year period 2019-2023, the preparation of observations will begin, before the arrival at Mercury in 2025
• ELT (Extremely Large Telescope): LESIA is responsible for the construction of adaptive optics for the European Southern Observatory’s (ESO) Extremely Large Telescope’s MICADO first-light instrument (at Co-I level). Aspects of system engineering, quality insurance and construction will strongly impact the LESIA activity in the coming years (2019-2023), with commissioning expected around 2025. It should be noted that beyond MICADO, the laboratory is involved in several projects related to other instruments of the ELT, such as CANARY, a demonstrator of adaptive multi-object optics which will be deployed in the ELT/MOSAIC second generation instrument. Research programmes on real-time calculators conducted through the French Agence Nationale pour la Recherche and European supporters are positioning LESIA at the first rank of laboratories ready to develop these subsystems for ELT instruments
• Solar Orbiter (European Space Agency/M1 mission): The delivery of the Radio and Plasma Wave (RPW) instrument to ESA in 2017 saw the completion of the implementation phase of this LESIA P.I. instrument devoted to wave analysis in the interplanetary medium. The next few years will see the preparation of observations and the ground segment, followed by observations in space with a launch planned for 2020. LESIA is also involved in the STIX instrument on Solar Orbiter processing software development and access to solar X-ray data
• SUPERCAM (NASA/Mars Science Laboratory 2020): LESIA is in charge, within a consortium led by IRAP (Institut de Recherche en Astrophysique et Planétologie, Toulouse, France), for the construction of the InfraRed Spectrometer IRS, in the near infrared domain. A strong participation in system engineering is also provided by LESIA for the ‘Mast Unit’ module, which connects the optical head of the Martian module to the instrument. Delivery of the instrument is expected in 2018 for a mission launch in 2020.
• James Webb Space Telescope (NASA/ESA): The exploitation of data from the JWST will be a strong focus of research at LESIA over the next five-year period: a guaranteed time commitment is ensured in the MIRI instrument after the provision of its coronograph by LESIA. However, the preparation of requests for observations in open time is also already in progress, mainly between the planetology and HRAA poles on different themes
• PLATO (ESA/M3): LESIA is involved in this middle class ESA mission for the supply of flight software and the preparation of observations. Scheduled for launch in 2026, the period 2019-2023 will see the delivery of packages (software, participation in the ground segment) required for LESIA
• ARIEL (ESA/M4): With the study of exoplanet transit spectroscopy, LESIA will have an involvement planned in the AIT phases (assembly, integration, tests) and calibration of the spectrometer, in conjunction with other French laboratories (IAS/Orsay and AIM/Saclay)
• Nanosatellite projects for science: 2018 has seen the launch of the first French science nanosatellite PICSAT, which was fully assembled and conceived by LESIA. Despite a limited operation time of three months, the experience in nanosat systems will prove highly valuable for future activities in this rapidly expanding field
Other projects with significant LESIA participation concern: the interferometry on the Very Large Telescope’s (GRAVITY instrument) which, in 2018, provided unprecedented views of the Galactic Center; radio science with LOFAR in collaboration with the Nançay instruments; and, in the recent past, Rosetta observations on comet Churyumov-Gerasimenko, ‘Cassini observations on Saturn and Titan and Mars and Venus Express observations on telluric planets, and many others smaller participations.
Paris Astronomical Data Center (PADC)
LESIA is strongly involved in this observatory service in the areas of solar physics, Europlanet (see below) and planetary databases. PADC is a flagship action of the Observatoire de Paris, under supervision of the French Institut National des Sciences de l’Univers of CNRS, as a Center for Regional Expertise. It is the result of the continuation of previous actions since 2002 (the Multi-training plan Virtual Observatory, Priority Axis VO-Paris Data Center in 2008). LESIA is mainly active in the topics of planetology, heliophysics, stars and the distant Universe. The involvement of LESIA is not only in the data supply, but also in PADC management, in the development of the archive standard of data in planetology (EPN-TAP), as well as in the support to the implementation of databases thanks to the involvement of engineers in projects, with a global contribution of 5.5 FTE.
Space weather activities
In addition to science in solar and plasma physics devoted to the interpretation of Coronal Mass Ejection of the Sun and their propagation to the Earth environment, LESIA is also following activities to develop a European network for space weather activities, working towards the development of alert systems in case of major solar storm events potentially affecting human activities. This co-ordination of activities is made within the frame of space agencies (CNES, ESA).
LESIA has participated in the funding of the Europlanet 2020 Research Infrastructure (EPN2020-RI) which, since its creation in 2004 (under FP6, then FP7 and Horizon 2020), enjoys substantial support from the European Commission (€10m in 2015). This is a complex and large-scale project involving 33 beneficiaries and 22 partners from 17 European countries and other associated countries (see: www.europlanet-2020-ri.eu).
EPN2020-RI is a platform that allows the European global community to meet (especially through the annual EPSC congress), discuss, distribute and share data and results, imagine and propose programmes, and generally promote the organisation of the global community to better respond to current technological and scientific challenges.
LESIA is represented in several important levels of this project, including the co-ordination, the executive committee and the council, and the management and implementation of the VESPA module, which offers the possibility to access data and services related to planetary sciences via a Planetary Science Virtual Observatory (see: http://vespa.obspm.fr), as well as in the dissemination of knowledge and the organisation of the EPSC conference (see: http://www.epsc2017.eu/)
Dr Pierre Drossart
LESIA, Observatoire de Paris, Université PSL,
CNRS, Sorbonne Université, Université Paris-Diderot