That´s a good question ... on the other hand the highest SC speed I ever saw was something between 600-800c.
Even with this speed a single ly distance would require you to spend half a day of constant flying to approach the target.
I somehow doubt anyone tried this
the speed can go much higher than 800c - I've been to 1700c before I decided to jump. The problem with people trying it at the moment, is that they are going to places like SOL which isn't even in the bubble. What I would suggest is wait until the game is released THEN try it. Find a system that is a small jump away e.g. 4LY and head in that direction.
it will probably still take more that 24 hours, so ensure you leave the pc alone and pointing in the correct direction, test in a starting sidewinder so if you run out of fuel you can always self destruct.
The guy who made it to SOL, basically nothing loaded for him - personally I think SOL isn't in the game "officially" yet as that is outside the bubble and it is unique to the game as it's our homeworld. When players arrive at earth they will have to make the planet look like earth and not some random generated texture.
So, wait for release, find a close system and head in that direction, I've seed the SC speed go over 2000 in some screen shots, it's just a long way to be prepared to wait....
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