“Blake’s 7” was a British dystopian version of “Star Trek” that aired from 1978 to 1981, for four seasons, and ended in a fashion almost as controversial as the end of the original “Neon Genesis Evangelion” TV series. I won’t give away any spoilers as the series is up on “YouTube” and well worth watching. Or rewatching, as I am doing.
The setting is a Future where the ‘Federation’ has become a force against human freedom, some 800 years or so years from now. Roj Blake, the eponymous revolutionary, led the most visible campaign against the Federation some years before the first episode, “The Way Back”, but had been mentally reconditioned and his memories of being a leader had been suppressed. A new resistance/protest movement had recontacted him, hoping to revive his memories… with predictable results. In the first few episodes Blake collects his ‘seven’ – Kerr Avon, computer hacker; Vila Restal, a master thief; Jenna Stannis, a space smuggler/pirate; Oleg Gan, a murderer with an brain-implanted ‘Limiter’; Cally, a telepathic outcast; Zen, a talkative starship computer, and the starship itself, “The Liberator”.
In the first 2 episodes, Blake is sent on an eight month voyage to a prison planet, Cygnus Alpha. The prison ‘barge’ he is transported in is the “London”, which cruises at ‘Time Distort five” through ‘hyperspace’. TV planet names never seem to follow any logical system (real star names are seemingly random to the uninitiated anyway) so suggesting “Cygnus Alpha” is a planet of “Alpha Cygnus[Cygni]” is only a stab in the dark. Alpha Cygni, or Deneb, is a very large, bright star about ~800 parsecs away (2,600 light-years) which implies a cruise speed for the “London” of ~3,900 c. As 5^6 = 3,125, let’s assume that’s how Time Distort factors, as multipliers of lightspeed, are computed and see where that takes us. Thus ‘Cygnus Alpha’ is ~2,100 light-years away, which is within the current distance uncertainty.
The “Liberator” crew talk of ‘speed’ as “Standard speed” with some factor, typically “Standard by 6” if they’re in a hurry(ish) and “Standard by 12” (SB 12) when the pedal is to the floor. In Season 2 Episode 1, “Redemption”, the “Liberator” is reclaimed by its Makers, the System, in interceptors able to travel at SB 14.
In one episode, Season 2 Episode 8, “Hostage”, the “Libertor” is pursued by Federation Pursuit Ships, initially at TD 9, but are pushed to do Time Distort 10, at a pinch. They encircle the “Liberator” but the crew fight their way through and pull away at “Standard by 12”, which the Pursuit ship Mutoid crew report as “Time Distort 20”. Interestingly, using TD 20 as (20)^5 = 3,200,000 c = (12.14)^6, thus suggesting the relationship between “TD” and “SB”. Thus TD 10 is SB 6.8, and TD 9 is SB 6.24, which implies Blake’s usual cruising speed of SB 6 is not much slower than the Federation’s nominal top-speed.
In the climactic conclusion to Season 2, “Star One”, the crew have to fly out of the Milky Way to ‘Star One’, the heart of the Federations computer control and its source of power. Blake and crew quickly realise that Star One has been compromised by an extra-galactic enemy, from M31. One might think that the 2.55 million light-years to Andromeda’s Great Spiral Galaxy would be straightforward at Standard by 12, but intergalactic travel is said to take ‘a lifetime’. By the speeds we’ve computed above it’s about 43 years at TD 9, or ~55 years at SB 6. The “Liberator” can’t sustain SB 12 for significant periods of time, without spending days regenerating its powerbanks, suggesting why no one had ever attempted intergalactic travel. Having a ‘power convertor’ blow-out a million light-years from home is a good reason not to push the hyper-drives too hard.