The Euclid project

Cristobal Padilla

The Euclid group at IFAE is lead by Cristobal Padilla, who is the Project Manger of the NISP-FWA and coordinates the group of engineers and technicians to fulfill the Institute responsibilities in Euclid. Some of the postdocs and students in the Cosmology group also help, specially in the preparation of the data and usage of PAU for Euclid science.


Euclid is a mission for the European Space Agency (ESA) Cosmic Vision (CV) 2015-25 programme to explore how the Universe evolved over the past 10 billion years to address questions related to fundamental physics and cosmology on the nature and properties of dark energy, dark matter and gravity, as well as on the physics of the early universe and the initial conditions which seed the formation of cosmic structure.

Euclid Goals

To accomplish its goals, Euclid will carry out a wide survey of 15,000 deg2 of the sky free of contamination by light from the Milky Way and the Solar System and a 40 deg2 deep survey to measure the high-redshift universe. The complete survey represents hundreds of thousands of images and several tens of Petabytes of data. Euclid will observe about 10 billion sources out of which more than one billion will be used for weak lensing. Several tens of million galaxy redshifts will be also measured and used for galaxy clustering. With these images Euclid will probe the expansion history of the Universe and the evolution of cosmic structures by measuring the modification of shapes of galaxies induced by gravitational lensing effects of dark matter and the 3-dimension distribution of structures from spectroscopic redshifts of galaxies and clusters of galaxies. Euclid data will provide improvement factors of ~30 in the measurement of the neutrino mass and up to ~400 in the uncertainty of the parameters of the cosmology state equation and will leave legacy catalogs in may areas of galaxy science with exquisite imaging quality and superb Near Infrared Spectroscopy.
Figure 1: Artist View of the Euclid satellite (Copyright ESA).

Euclid Instruments

The Satellite will be equipped with a 1.2 m diameter Silicon Carbide (SIC) mirror telescope made by Airbus Defense and Space feeding 2 instruments, VIS and NISP, built by the Euclid Consortium. These instruments are a high quality panoramic visible imager (VIS), a near infrared 3-filter photometer (NISP-P) and a slitless spectrograph (NISP-S). The IFAE is responsible for the design and manufacturing of the NISP Filter Wheel Assembly (NISP-FWA), a device that allows the NISP instrument to select the optical filter used for the images it takes.

IFAE contribution in 2020

During 2020, IFAE has been supporting LAM in the integration and testing of the FWA inside the NISP system. All this work has concluded in the delivery of NISP to ESA/AIRBUS in the middle of the year, where the complete instrument is being integrated inside the Euclid Satellite. The NISP-FWA is the first ever flight hardware for space built and qualified at IFAE.

On another front, the group has started activities inside the Euclid consortium to exploit the data and contribute to the scientific output of the mission. The activities have been more focused in the analysis of the PAU data with Machine Learning techniques, where we have made studies on star-galaxy separation, background prediction and Photometric redshift measurements with deep learning techniques. We have also joined the new Machine Learning Working group in Euclid to start exporting these techniques to this survey. Additionally, Cristobal Padilla is the chair of the Euclid Speaker’s Bureau and activities to build the software infrastructure to serve the consortium in this area have started within IFAE.


ASTEROID is an H2020 project aiming at enabling Europe to acquire the technology and knowledge necessary to manufacture 2k^2 high performance Infrared Focal Plane Arrays, define the types of products to design and define the strategy to create an industrial manufacturing line of these detectors. IFAE is partnering with companies and institutions in France and Austria to develop a low noise and low dark current detector that will be directly useful for astronomy application in both ground telescopes (ESO) or space telescopes (ESA).

IFAE’s responsibility is in the optical and electrical characterisation of the detector. During 2020, we have commissioned the equipment used and modified for Euclid GSE to perform the thermal cycles needed in a controlled and secured way. The system has reached a relative temperature error of 0.5 mK. At the same time we have also integrated all the optical elements needed for the detector characterisation. The European Southern Observatory (ESO) New Generation Controller (NGC) for the test of the Infrared Sensors has been delivered and started its commissioning, waiting for the delivery of the Lynred detectors.

This project will allow IFAE to acquire the know-how in characterizing IR sensors for Astronomy and Space and establishes a possible link of future collaboration with other ESO missions and their world-class telescopes located in the Atacama Desert in Chile. More information can be found in , maintained by IFAE as communication responsible of the project.