Infrared Space Observatory

The Infrared Space Observatory (ISO) was a space telescope for infrared light designed and operated by the European Space Agency (ESA), in cooperation with ISAS (now part of JAXA) and NASA. The ISO was designed to study infrared light at wavelengths of 2.5 to 240 micrometres and operated from 1995 to 1998.

The €480.1-million satellite was launched on 17 November 1995 from the ELA-2launch pad at the Guiana Space Centre near Kourou in French Guiana. The launch vehicle, an Ariane 44P rocket, placed ISO successfully into a highly ellipticalgeocentric orbit, completing one revolution around the Earth every 24 hours. The primary mirror of its Ritchey-Chrétien telescope measured 60 cm in diameter and was cooled to 1.7 kelvins by means of superfluidhelium. The ISO satellite contained four instruments that allowed for imaging and photometry from 2.5 to 240 micrometres and spectroscopy from 2.5 to 196.8 micrometers.

ESA and the Infrared Processing and Analysis Center made efforts to improve the data pipelines and specialized software analysis tools to yield the best quality calibration and data reduction methods from the mission. IPAC supports ISO observers and data archive users through in-house visits and workshops.