Laboratory organization

Setting up the Laboratoire Temps Espace

The Laboratoire Temps Espace (LTE) was created on January 1, 2025. It is the result of the merger of two former Paris Observatory entities: SyRTE (Système de références du temps et de l’espace) and IMCCE (Institut de mécanique céleste et de calcul des éphémérides). The organization has changed, but the research activities are continuing, and the themes of both have been maintained.

Research themes

The Laboratoire Temps Espace is a multi-disciplinary laboratory comprising nine research teams with expertise in time, space and the history of science:

  • it is dedicated to the study and realization of space-time reference systems and their applications to fundamental physics tests, using astrometry, analysis of the Earth’s rotation, laser telemetry to the Moon, time and frequency metrology;
  • It also carries out scientific research in the fields of atomic interferometry and quantum inertial sensors, celestial mechanics, dynamical systems and astronomy;
  • it aims in particular to improve knowledge of the solar system and its exploration, and carries out research directly necessary to its public service mission;
  • it is also involved in the history of science as it relates to astronomy.

Societal missions

The Laboratoire Temps Espace is responsible for the two societal missions entrusted to Paris Observatory by the French government:

  • the design and distribution of French legal time,
  • the production and distribution of solar system body ephemerides.

Space and industrial activities

LTE research teams are heavily involved in space activities in conjunction with CNES and the European Space Agency (ESA). They contribute to the design and operation of observation instruments onboard space missions, and deploy observation and monitoring technologies on the ground.
The technologies developed at LTE in electronics, metrology and gravimetry have direct applications in industry.

Guardianship

Laboratoire Temps Espace is a department of Paris Observatory_PSL and a CNRS Research Unit (UMR 8255). The Laboratoire national de métrologie et d’essai (LNE) and Sorbone Université are also trustees of the Laboratoire Temps Espace, as well as the University of Lille, with which the laboratory is associated.

The staff

The Laboratoire Temps Espace brings together some thirty researchers and teacher-researchers, fifteen post-docs, twenty PhD students and around thirty-five engineers and technicians (including ten fixed-term contracts).

Teaching and training

LTE researchers teach courses on subjects related to the laboratory’s research themes at Paris Observatory and at several universities (Sorbonne Université, Université Paris-Cité, Université Paris-Saclay, Université Paris-Dauphine, ENS, Université de Lille, IPSA).
They are also involved in continuing education through the University Diplomas (DU) offered at Paris Observatory.
The laboratory welcomes doctoral students, undergraduates and masters students, as well as engineering students on 2-6 month internships, supervised by researchers.
Seminars and conferences are also offered and open to a wide range of audiences.

Specialized departments and divisions

The Laboratoire Temps Espace relies on a number of specialized departments and divisions to carry out its operations and missions: