1964 Elkes Biscuits Ltd. : Do You Know?

Do You Know? trading cards were issued in 1964 by Elkes Biscuits Ltd. in England. The 25-card illustrated series presents information on a wide variety of scientific subjects. Each card measures approimately 1.44 x 2.69 inches (37 x 68 mm).

The series features the North American X-15-1 hypersonic research aircraft (56-6670). The card illustration incorrectly depicts multiple rocket engine nozzles. The experimental vehicle was first piloted in an unpowered glide by Scott Crossfield on June 8, 1959. NASA developed three of the aircraft to investigate problems that pilots would encounter near the edge of space. The X-15-1 is currently held by the Smithsonian National Air and Space Museum. The aircraft is displayed in the Steven F. Udvar-Hazy Center at Dulles International Airport in Virginia.

"Just as waves build up ahead of a fast moving boat, so do waves form in front of a fast aeroplane. They travel at the speed of sound, which is about 760 m.p.h. When the aeroplane exceeds this speed it comes up against the still air and it makes a tremendously loud bang as it hits what is called the "Sound Barrier." Supersonic aircraft, like the X15 (U.S.A.), shown here, have very small wings, to cut down air resistance. The X15 was designed for research into the lower reaches of space and has reached altitudes of over 40 miles."

The collection includes Ariel 1, the first British-American satellite. The spacecraft was named after the spirit character in The Tempest by William Shakespeare. On April 26, 1962, Ariel 1 was launched into low Earth orbit aboard a Thor DM-19 Delta rocket. The onboard experiments measured solar radiation in the ionosphere. The satellite was damaged by fallout from the Starfish Prime high-altitude nuclear test conducted on July 9, 1962. Ariel 1 reentered the atmosphere on May 24, 1976.