The joint UK/USA satellite Ariel V was launched by Scout B-1 solid fuel rocket, on October 15th 1974 from the Italian Space Agency’s San Marco platform off the coast of Kenya. It was an x-ray observatory, with a camera and a variety of instruments provided via NASA and the (now defunct) UK Science and Engineering Research Council. Operations were controlled from the Rutherford-Appleton Laboratory in Oxfordshire.
Ariel V was the fifth of six Ariels, launched between 1962 and 1979. It’s orbit decayed on March 14th 1980. The name is probably a nod to the works of one of Britain’s biggest exports, William Shakespeare (I say this because our only other early satellite was called Prospero).
Ariel V produced several highlights, discovering long-period x-ray pulsars and x-ray transients (Nature, vol 261, 1976).