From 2003 to 2009 I worked at the Smithsonian Astrophysical Observatory, where I was part of the team that built and commissioned the InfraRed Array Camera (IRAC) onboard the Spitzer Space telescope. Spitzer is the last of NASA “Great Space Observatories” (the others are the Hubble Space Telescope, the Chandra X-Ray and the Compton Gamma-Ray Observatories). Launched into space by a Delta rocket from Cape Canaveral, Florida, on 25 August 2003, it is currently orbiting the Sun in a “Earth Trailing Orbit”. With its 85 cm primary mirror, cryogenically cooled by a reservoir of LHe, Spitzer is the largest infrared telescope ever launched into space.
The IRAC camera provides simultaneous 5.2’x5.2’ images in four bands at 3.6, 4.5, 5.8 and 8.0 μm and was designed with sensitivity in mind: among its most spectacular accomplishments in the first 5 years of its mission are the first direct detection of light coming from an extrasolar planet, the first mapping of the surface temperature of another planet, the light that may come from the first objects in the universe, and fundamental contribution to understand star formation, the interstellar medium, stellar populations including brown dwarfs, galaxy evolution and dynamics, and cosmology. After the exhaustion of the Spitzer cryogenic in May 2009, IRAC is still able to operate without loss of performance at 3.6 and 4.5 μm, during the ongoing “warm” mission after the end of the nominal Spitzer operations.