NASA space tech: From Pioneer to Curiosity
Summary: As Voyager celebrates its 35th birthday and Curiosity starts on the most exciting Mars mission ever, we look back at the IT under the hood of six NASA projects that have made science fiction into everyday fact.
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The same technology that has revolutionised our lives has changed space science forever, building ever-cleverer robots exploring ever farther into space.
As the Voyager probes celebrate their 35th birthday and prepare to leave the Solar System, and as the Curiosity rover starts on the most exciting Mars mission ever, we look back at the IT under the hood that has made science fiction into everyday fact.
Pioneer 10
Launched in 1972, Pioneer 10 (above) was the first imaging mission to fly past Jupiter, Although it is widely reported that it used an Intel 4004 processor for navigation, mission sequencing and communication, it in fact used a custom processor system built from a variety of standard logic chips, with individual commands handled by dedicated circuits.
Storage was 49,152 bits of magnetic core memory, which was too heavy to be expanded further. But alternatives were pricey — a proposed upgrade to 1 megabit (256kB) of chip memory for a later mission was priced at $630,000 in 1974.
Pioneer 10 and its sister probe Pioneer 11 were the first missions to have a recognisably modern computer system capable of multiple commands and a measure of independent operation, due in part to the availability of high-density logic chips and the need to manage short, high-intensity science-gathering flypasts at a distance from Earth that precluded direct commands in real time.
However, they were still recognisably derived from earlier probe thinking, where pre-programmed sequences unaffected by local information drove manoeuvres.
An in-depth NASA design document discussing the Pioneer architecture and future developments into what would become the Voyager probes can be found here (PDF).
Image: NASA
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Talkback
Bits Bytes and nibbles
How many bits were there in a Byte in 1974? :-)
bits
Sheridan's quibble wasn't with the nibble...
kB, I mean
Far too subtle...
I don't think it's ever used as an abbreviation as it could be confused with Newtons but, just perhaps...
1mb = 265kn = 128kB
Byte
Byte, undefined?
While the term 'word' often needs clarification it is now usually thought of as 16 bits but some of us remember the PDP8 with words of 12 bits. Interestingly, the usual source quotes the 4004 as using '4 bit data words' (not bytes). However, Intel data for the 4004 refers to one word instructions being 8 bits and two word instructions being 16 bits - but I don't see them mentioning bytes anywhere.
So, Superbiker, I take your point regarding absolute definitions and I will even say; "Mea culpa". But... with the wide acceptance of byte meaning 8 bits, perhaps journalists could make it clear when they mean another size. I've never had to check that a hard disk or RAM that quotes the size in bytes means 8 bit per byte - and I hope I don't have to start now. (Bad enough that hard disks use powers of 10 while the rest of IT uses powers 2).
So, officially ??? -
bit = single binary digit (1 or zero)
nibble = group of four bits
octet = 8 bits or 2 nibbles
byte = one or more bits (context dependant)
word = one or more bits (context dependant)
I need to go and edit/clarify a lot of my documents - and try to work out if I've bytten more or less than I can nibble!
One small correction