LIRA, a pioneer in astrophysics and instrumentation, pushes back the frontiers of knowledge
LIRA
Laboratory for Instrumentation and Research in Astrophysics
LENS: LIRA – Weekly Highlight
Credit: Cordiner et al., Nature, 2026 / NASA-ESA-CSA JWST / ALMA
3I/ATLAS, a comet from the Galactic cold
10 August 20263I/ATLAS, the third confirmed interstellar object to pass through our Solar System, carries a chemical signature unlike that of any known comet. Observations with the James Webb Space Telescope, complemented by ALMA data, reveal water highly enriched in deuterium and carbon isotopic ratios very different from those measured in Solar System bodies. These clues suggest that 3I/ATLAS formed in a very cold environment, probably below 30 K, within an ancient and relatively metal-poor planetary system. With contributions from LIRA researchers Nicolas Biver, Dominique Bockelée-Morvan and Jacques Crovisier, this result makes 3I/ATLAS a preserved fragment of another planetary system — and possibly a witness to the early chemical history of the Milky Way.
News
Institutional news
26 June 2026
The International Astronomical Union has recognised Antonin Wargnier’s doctoral thesis, carried out at LIRA
Presentation
LIRA, a CNRS joint research unit at Paris Observatory, is a laboratory of excellence in astrophysics and instrumentation. It studies astrophysical objects, from the Solar System to our Galaxy and beyond, through five thematic areas. Through international collaboration and instrumental innovation, it pushes back the frontiers of science and contributes to the training and dissemination of knowledge.
Our projects
MIRS on the JAXA MMX mission
The Martian Moons eXploration (MMX) mission of JAXA (Japan Aerospace Exploration Agency) is the first sample-return mission from the Phobos satellite. It also includes an exploration of the Martian system. The mission’s primary objective is to decipher the origin of Martian moons, which will provide important information on planet formation and the conditions for the emergence of water on Earth-like planets.
The MIRS (MMX InfraRed Spectrometer) instrument, developed under the leadership of LESIA (now LIRA), is an imaging spectrometer that will characterize the composition of the Martian system and help select candidate sites for sample collection.
GRAVITY+
The GRAVITY instrument, installed on the European Southern Observatory’s Very Large Telescope Interferometer (VLTI/ESO), has produced spectacular and transformative results on the supermassive black hole at the centre of the Milky Way, the active nuclei of other galaxies, proto-planetary disks around young stars and exoplanets. GRAVITY+ aims to modernise both VLTI and GRAVITY to make them ≈ 100 times more sensitive, while increasing sky coverage by a factor of ≈ 100, and contrast in the vicinity of bright objects by a factor of ≈ 10. These gains will benefit all the VLTI’s current and future instruments for the next 20 years, and will perpetuate it as a unique infrastructure in the world.
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Contacts
Contacts
Postal address
Observatoire de Paris
5, place Jules Janssen
92195 Meudon
Phone
01 45 07 77 01
Meudon site
LIRA
Observatoire de Paris
5, place Jules Janssen
92195 MEUDON Cedex
Paris site
LIRA
Observatoire de Paris
77, Avenue Denfert-Rochereau
75014 Paris
Cergy site
LIRA - Site de Neuville II
UFR Sciences et Techniques - Département de physique
5, mail Gay Lussac
95000 Neuville-sur-Oise
