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    "The first machine in orbit"

    Gemini 3 Flown Random Access Non-Destructive Readout 4096 Bit Memory Plane from the Gemini Spacecraft Computer. A 4.25" "memory chip" contained inside a 4.75" x 4.75" x 0.5" acrylic display with the following on a typed label: "One plane of RANAM (Random Access Non-Destructive Readout) Memory containing 4096 bits of information. This memory orbited the earth in the Gemini mission, March 23, 1965." This was a part of the first Gemini Spacecraft On-Board Computer ever to fly on a manned mission. The Mercury missions had no real need for a computer on board as their orbital path was dependent on the Atlas booster and re-entry retrofire times and firing attitudes were calculated on the ground and transmitted to the spacecraft while in flight. For the more aggressive goals of the Gemini program, aided by the addition of a second astronaut, an on-board computer was needed to function in six mission phases: prelaunch, ascent backup, insertion, catch-up, rendezvous, and re-entry. This device was designed and manufactured by IBM's Federal Systems Division, in Oswego, New York. "The computer weighed approximately 59 pounds, performed more than 7,000 calculations a second, and needed no more room than a hatbox - 1.35 cubic feet - aboard the Gemini. It had an average power consumption of 94.54 watts, a 500 kc bit rate, a memory cycle time of 250 kc and an add time of 140 microseconds. The computer's memory was a random-access, nondestructive readout design with flexible instruction and data storage organization. Its nominal capacity was 4,096 39-bit words and its operational capacity was 12,288 13-bit words." (IBM's historical archives). The pushbutton and display devices were mounted on the Gemini co-pilot's instrument panel (printed chart included). This particular memory plane flew on Gemini 3, the first two-man American mission, with Gus Grissom and John Young aboard, March 23, 1965. An incredibly rare and desirable piece of equipment, part of the "first machine in orbit." Should hold interest for both Space and Computer historians and collectors. Included with the lot is a thirty+ page technical document printed from the excellent website. Fine.

    Designers of this Gemini Digital Computer can claim an impressive list of firsts:
    · The first digital computer on a manned spacecraft.
    · The first use of core memory with nondestructive readout. The machine was designed in an era of rotating drum memories, its designers considered it a step forward.
    · IBM's first completely silicon semiconductor computer.
    · The first to use glass delay lines as registers.
    · Technologically advanced in the area of packaging density.
    · The first airborne or spaceborne computer to use an auxiliar
    (Source: NASA's "Computers in Spaceflight")

    Auction Info

    Auction Dates
    November, 2015
    6th Friday
    Bids + Registered Phone Bidders: 19
    Lot Tracking Activity: N/A
    Page Views: 14,409

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