– A European contribution to HWO

Pollux

High-Resolution Spectroscopy & Polarimetry for HWO

Pollux is the first instrument ever designed to perform spectropolarimetry from space across a continuous wavelength range from the far ultraviolet to the near infrared. Proposed as a European contribution to NASA's Habitable Worlds Observatory (HWO), it will characterise stellar and planetary magnetospheres, trace the baryon cycle across cosmic time, and probe the atmospheres of exoplanets in search of life.

The main science cases of Pollux cover three interconnected themes: stars, (exo-)planets, and cosmic ecosystems — all organized around the core HWO science portfolio. Since the parameter space opened by Pollux is essentially uncharted territory, its potential for ground-breaking discoveries is tremendous.

– LATEST NEWS

February 2026

The Pollux Instrument Concept for HWO

New paper by Neiner et al. presenting the full Pollux concept: design, science drivers, technology challenges, and the consortium organization.
arXiv:2602.09828

8–10 April 2026

Pollux Workshop — Leuven

The Pollux consortium will meet in Leuven to review the science cases that have been proposed, define the final trade-offs of Pollux, and discuss some critical technologies and engineering issues.

https://fys.kuleuven.be/ster/events/workshops/2026/pollux

December 2026

HWO Europe Symposium — Massy (near Paris)

please visit HWO2026’s website:  https://hwo2026.obspm.fr/….

Pollux and Stellar science
Pollux and Planets
Pollux and science of cosmic ecosystemS

– Pollux in a nutshell :
WAVELENGTH COVERAGE
Some instrumental facts

5 channels
FUV · MUV · NUV · OPT · NIR

5 high-resolution spectrographs
R ~ 100 000

Simultaneity from MUV to NIR
4 channels at once

Circular and linear polarimetry from 120 nm to 1.9 microns

Slit Spectroscopy in MUV and NUV
3 » slit

– Technology developments for Pollux
  • gratings and optics
  • detectors
  • coatings
  • mechanics
  • electronics
  • software

The Pollux Consortium

Pollux is developed by a consortium of European scientists and institutes

Supported by national space agencies, under French (CNES) leadership

Washington D.C. July 2025

Meet the Project Office

From left to right : 
  • David Le Mignant, Project Manager
  • Coralie Neiner, PI
  • JC Bouret, co-PI
  • Luca Fossati, Instrument Scientist

To reach us, send an email at pollux.po@lam.fr

If you want to join us

To register to a mailing list of information, send an email to sympa@lam.fr with an empty body and a subject line of the form:
subscribe list Firstname Lastname

where you should replace “Firstname Lastname” by your name and “list” by the mailing list you want to subscribe to. To subscribe to several lists, they you must send several emails (one per list).

The different mailing lists are:

pollux.consortium@lam.fr for the global Pollux consortium
pollux.science@lam.fr for the Pollux science consortium
pollux.payload@lam.fr for the Pollux payload consortium
pollux.swg-stars@lam.fr for the Science Working Group about Stars
pollux.swg-planets@lam.fr for the Science Working Group about Exoplanets (including solar system planets)
pollux.swg-cosmic@lam.fr for the Science Working Group about Cosmic ecosystems (ISM, IGM, CGM, galaxies, cosmological probes,…)