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This Day in Science Fiction History: 4 July

Fictional Entry—Thursday, July 4, 1996

Scene from Independence Day where the David Levinson uploads his virus to the mothership showing a screenshot from his Macintosh PowerBook.
Uploading the Jolly Roger virus to the Harvester Mothership. (© 20th Century Fox 1996)

Excerpted from Wired Magazine 4.10, October 1996, The (Cyber)War of ’96 (pages 120-123, 166-170)


Wired: How did you know the code would work?


Levinson: I didn’t. Not for certain. I’d figured out the code language the Harvesters were using was binary based. Never did truly figure out the language or their coding. It took a bit of fiddling. But I found it. Once I had that done, half the work was finished. Well, half the work for clearing up the signal from the satellites.


Why satellites?


That’s where I first saw the code. As soon as the Harvesters entered orbit, they stated commandeering bandwidth on communications satellites. I was working at Compact Cable then, before, well, we all know what happened to New York City. Anyway, Marty Gilbert, my boss at the time, called me in because the feed to the satellites was getting heavy interference. Took some time but I was able to find the binary signal and wrote and algorithm in order to clear out the signal. Same way you can cancel noise by inverting the waveform. By the time I’d figured that out, I’d also figured out there was a countdown imbedded in the signal.


Which led you to the White House.


Yes. Which, in turn because of the attack, led to the President Whitmore taking us all to Area 51 in Air Force One.


You’re willing to say on record you went there? That Area 51 exists?


Chuckles. With what happened, the number of people who came there for safety, and how President Whitmore led the attack on the City Destroyer from there, kind of hard to hide it now. Yes, I spent several hours in the hanger with a scout craft. Similar to a Harvester fighter, but with lighter weapons and heavier shields.


The one that crashed at Roswell in 1947?


Yeah. Turns out my father was right. It was a government cover-up. Not that President Whitmore knew about though. He was as confused as the rest of us. The ship was most likely part of the scout force sent ahead to investigate if Earth was ready for harvesting. How it crashed is still a mystery.


The scientists at the base, good guys all, hadn’t been able to power the ship for almost 40 years. Not until the mothership came into orbit. Which meant they’d only scratched the surface of what the hardware in the ship could do. My work decoding the signals gave me a little leg up. Hardest part was interfacing my laptop with the ship. Thankfully, while they hadn’t been able to power things, they had done a huge amount of hardware research. Turned out a lot of our modern electronics tech was based on work those scientists had done. They were able to build an interface to connect my laptop to the ship. Which meant once we docked, I had a direct connection to the mothership’s computers.


There wasn’t any security on their systems. None. I’d figured that out back on day one. Proved it once I was able to interface with the computer system on the scout craft. The Harvesters probably never even thought of it since all the Harvesters are telepaths. Biological drones with no individuality.


Chuckles again. No rebels or hackers.


How did you manage to write a virus to take down the mothership?


I didn’t. I wrote Jolly Roger as a simple interface blocker. It was designed to stop the signals from and to the mothership for a short time. I basically wrote it using a modified floating-point cypher based on a combination of the Fibonacci sequence and a multi-digit prime number encryption subset to overload the communication channels. Same channels they’d been using with the satellites. Most of the program was based on that signal blocking scheme. I didn’t figure it would work more than a minute or two, if at all. It was a Hail Mary moment. But it worked.


As to why it worked, that’s harder. The current theory is that the City Destroyers weren’t independently controlled. Everything about the Harvesters is about central control. Those big ships were basically drones. So, when the signal stopped, they weren’t receiving control anymore. The shields went down because the order to keep them up had been coming from the mothership. No signal, no shields.


It was the nuclear missile Captain Hiller launched that took down the ship. Jolly Roger kept the mothership unable to signal the City Destroyers. That’s it. The explosion destroyed something vital in the mothership, causing it to explode. The glory goes to Hiller and his ability to fly an alien fighter he’d never touched before that mission.


Independence Day

Motion Picture

20th Century Fox



This Day in Science Fiction History examines notable events, real and fictional, concerning fantasy and science fiction in various media


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