Also I know that this has nothing to do with Diamond Days but I calced the speed of that ship Pearl built back in Season 2, and it's pretty impressive.
So Pearl was taking the ship to the "nearest Star system" to Earth, which according to
this article on Nasa's website, is Proxima Centauri, which is 40,208,000,000,000 km away from Earth. She said it would take 50 years for them to get back to Earth, so assuming it takes them half the time to get there and half the time to get back that's 25 years to reach Proxima Centauri. Plugging that into
this calculator gets a speed of 50,999,500 m/s.
Then, taking 50,999,500 m/s and plugging it into
this m/s to mach speed calculator we get a mach of 149870.7. Finally, taking that mach and putting it into a
light speed conversio calculator we get 0.17% the Speed of Light.
Within less than a day, Pearl built a relativistic ship. Quite an impressive feat if I do say so myself. And I do.
Please don't tear me apart if I got this wrong this is my first calc ever.