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New Horizons Spacecraft Wakes Up To Prepare For Historic Flyby of Distant Object (space.com)
jwhyche writes: The New Horizons space probe has been in hibernation mode since Dec. 21. On June 5th, the spacecraft exited hibernation mode and began preparing for its next encounter. The spacecraft is currently 3.7 billion miles from Earth and will be spending the next few months preparing for its flyby of a small Kuiper Belt object nicknamed Ultima Thule (officially 2014 MU69). The craft is expected to pass by Ultima Thule during the New Year's holiday.
You never compress code in those situations. Data maybe.
It's a bit misleading to say uploading new software. You never upload *new* software on flight hardware in the sense that most people would understand it. The risk of anything going wrong is just too large, a lot of things are hardcoded and data transmission speeds are crap.
It's usually just uploading a different set of commands that are handled onboard the existing software. So in terms of data size its very small.
In this case it probably concerns more the science instruments, so it's more like telling different instruments to switch modes and configurations to adapt for the new environment.
I'm going to be generous and—rather than ask for a citation I know doesn't exist—assume that you were trying to be funny.
He may be alluding to the first transatlantic cable (1850s), where they didn't fully understand electromagnetic signal propagation, and they damaged the cable by overdriving it with high voltage in an attempt to improve reception. Before it completely failed, the bandwidth became so low that it took a whole day to send a single short message.
Any individual bit sent was much shorter, of course, but the signal-to-noise ratio was so bad that it took a long time to decipher each bit. So in practical terms, it wasn't really anywhere close to the speed of light.