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Voyager 1 and 2 were launched in 1977, thirteen years before Tim Berners-Lee's first web server went online at CERN at the end of 1990. Both probes are still working, run by onboard computers that carry out about 8,000 instructions a second; a modern phone manages billions.

NASA and CERN

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The probes date from the dawn of the home computer: they left Earth in the same year that the Apple II, one of the first mass-produced personal computers, went on sale. Each Voyager carries three kinds of computer, two of each for safety: one runs commands, one keeps the craft pointed in the right direction and one packages the science data. Together the six hold about 68 kilobytes of memory, far less than a single photo taken on a modern phone. Data were stored on a tape recorder and sent home by radio. In November 2023 a failed memory chip left Voyager 1 sending meaningless data. Each command took nearly a day to reach it, yet engineers moved the affected code to other parts of its memory, and by April 2024 the probe was sending usable data again.

Türkçe oku
Voyager 1 ve 2, 1977'de fırlatıldı; Tim Berners-Lee'nin CERN'deki ilk web sunucusu ise on üç yıl sonra, 1990'ın sonunda çalışmaya başladı. İki sonda da hâlâ görevde. Onları yöneten bilgisayarlar saniyede yaklaşık 8.000 komut işliyor; bugünkü bir telefon ise saniyede milyarlarca komut işleyebiliyor.

Sondalar ev bilgisayarı çağının başından kalmadır: İlk seri üretilen kişisel bilgisayarlardan Apple II'nin satışa çıktığı yıl Dünya'dan ayrıldılar. Her Voyager'da, güvenlik için ikişer tane olmak üzere üç tür bilgisayar bulunur: Biri komutları yürütür, biri aracın doğru yöne bakmasını sağlar, biri de bilimsel verileri paketler. Altı bilgisayarın toplam belleği 68 kilobayt kadardır; bu, bugünkü bir telefonla çekilmiş tek bir fotoğraftan bile çok daha azdır. Veriler manyetik bantlı bir kayıt cihazında saklanıyor, radyo dalgalarıyla Dünya'ya gönderiliyordu. Kasım 2023'te bir bellek yongası bozulunca Voyager 1 anlamsız veriler göndermeye başladı. Her komutun sondaya ulaşması neredeyse bir gün sürüyordu; mühendisler buna rağmen etkilenen yazılımı belleğin başka bölümlerine taşıdı ve Nisan 2024'te sonda yeniden kullanılabilir veri göndermeye başladı.

Sources and further reading

Background reading: Voyager 1
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