ARGO is a 1.2m balloon-borne telescope, conceived in 1987 and flown in the stratosphere in 1988, 1990 and 1993. The instrument was designed to measure Cosmic Microwave Background anisotropies at angular scales around 1 degree.

In the 1993 flight the observation wavelengths were 2.2, 1.2, 0.8, 0.5 mm. The detectors were composite bolometers cooled at 0.3K. The beam was 0.56 degrees FWHM. The sky chop was sine wave at 14 Hz, with an amplitude of 1.8 deg peak tp peak. The instrument performed "step and integrate" scans of the sky, accumulating a data set of microwave temperature difference measurements in about 200 independent sky patches, in the Hercules and Aries/Taurus regions.

The general design of the experiment is described in

Here are links to photographs of

The scientific results from the ARGO flights are described in