There were one cosmic ray, two solar emission and three ionospheric experiments. This first in a series of 5 satellites was launched on a Thor Delta rocket on April 26, 1962. Ariel-1 provided data from launch until September 1962 and sporadically after that until it was turned off in November 1964. The artifact was rebuilt from original parts by technicians at GSFC and transferred from NASA in 1975.
Epoxy shell attached to internal aluminum structures provide mounting surfaces for instruments.
Britain was one of the first countries to accept this offer. The cosmic-ray Cerenkov counter consisted of a 10 cm hollow perspex sphere viewed by a photomultiplier tube, both located on the satellite spin axis. Spatial electron density distribution was determined by means of a radio-frequency density probe. Measurement of electric permitivity of the medium in the path of the satellite with a 10 Mhz radio frequency signal revealed regions of enhanced ionization on the topside ionosphere. X-ray emission from the sun in the 3 to 12 nM range was measured with argon filled proportional counters with 25 micron beryllium windows.