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: NASA, ESA, CSA, STScI, M.Cordiner (Catholic University of America, GSFC)
3I/ATLAS: A Chemical Portrait of an Interstellar Visitor
29 June 2026This image reveals the coma of 3I/ATLAS, the third interstellar object ever identified crossing our Solar System. An international team, including Nicolas Biver, Dominique Bockelée-Morvan, and Jacques Crovisier from LIRA, combined observations from the James Webb Space Telescope and ALMA to investigate the composition of this comet from another planetary system.
The three panels map different gases released as the comet’s ices sublimate under the Sun’s heat: from left to right, water (H₂O), carbon dioxide (CO₂), and carbon monoxide (CO). Their distribution around the nucleus, shown on a scale of 1,300 km per arcsecond, reveals the chemical structure of the gaseous envelope surrounding 3I/ATLAS.
These observations show that although the comet contains familiar molecules, their abundances—and especially their isotopic signatures—differ significantly from those measured in Solar System comets. 3I/ATLAS therefore represents a true time capsule, preserving valuable clues about the formation conditions of small bodies in a distant and ancient planetary system.
SEMINAR Thursday 9 July 2026 11:00
Séminaires du pôle HPA The Deep Synoptic Array: Revolutionizing Access to the Radio Sky
Séminaires du pôle HPA The Deep Synoptic Array: Revolutionizing Access to the Radio Sky
SEMINAR Thursday 16 July 2026 11:00
Séminaires HRAA Diffraction-limited exoplanet imaging at today’s observatories with photonic lanterns
Séminaires HRAA Diffraction-limited exoplanet imaging at today’s observatories with photonic lanterns
SEMINAR Monday 20 July 2026 11:00
Séminaires LIRA/LUX The HITRAN2024 molecular spectroscopic database: from protoplanetary disks to exoplanets
Séminaires LIRA/LUX The HITRAN2024 molecular spectroscopic database: from protoplanetary disks to exoplanets
News
Institutional news
26 June 2026
The International Astronomical Union has recognised Antonin Wargnier’s doctoral thesis, carried out at LIRA
Institutional news
8 June 2026
SKAO: the French astrophysics community gathers at the Paris Observatory-PSL
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.
All projects
Projets en développement
Projets en exploitation
Projets passés
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
