ESA and the James Webb Space Telescope

The James Webb Space Telescope (JWST) is a collaborative project between NASA, ESA, and the Canadian Space Agency (CSA). Although radically different in design, and emphasizing the infrared part of the electromagnetic spectrum, JWST is widely seen as the successor to the Hubble Space Telescope (HST).

MIRI, NIRSpec, Ariane 5
Images of the Flight Models of NIRSpec (top left) and MIRI (bottom left). The drawing on the right depicts JWST folded up in the Ariane 5 launcher.

The JWST observatory will consist of a deployable 6.6 meter passively cooled telescope optimized for infrared wavelengths, and will be operated in deep space at the anti-Sun Earth-Sun Lagrangian point (L2). It will carry four scientific instruments: a near-infrared camera (NIRCam), a near-infrared multi-object spectrograph (NIRSpec) covering the 0.6 - 5 μm spectral region, a near-infrared slit-less spectrograph (NIRISS), and a combined mid-infrared camera/spectrograph (MIRI) covering 5 - 28 μm. The JWST focal plane (see image to the right) contains apertures for the science instruments and the Fine Guidance Sensor (FGS).

The scientific goals of the JWST mission can be sorted into four broad themes:
  • The end of the dark ages: first light and re-ionization
  • The assembly of galaxies
  • The birth of stars and proto-planetary systems
  • Planetary systems and the origins of life
Although the first two of these themes are extragalactic in nature and concerned with exploring the formation of stars and galaxies in the remote Universe at the earliest times, they are intimately linked to the latter two mainly galactic themes, which aim at understanding the detailed process of star and planet formation in our own galaxy.

The European Space Agency is responsible for providing NIRSpec from ESA funds, and approximately half of MIRI through special contributions from the member states via a consortium of European science institutions (EC). As its non-instrument contribution, ESA will provide the Ariane 5 launcher that will place the JWST observatory in its orbit around L2. Furthermore, a number of ESA staff will be posted at the Space Telescope Science Institute (STScI) in Baltimore in support of the European payload components as ESA's contribution to JWST operations.

The purpose of this web-site is to provide information about the scientific aspect of the JWST mission and provide an update on news and upcoming scientific events connected with the Mission, taking place in Europe;  specific information about to the NIRSpec instrument, its performances and calibration are available here, while further information about the MIRI instrument can be found here.

JWST OTE Focal Plane


The focal plane of the JWST telescope with the assigned field of views for the instruments.