Easy, there, Pygmalion.
You realize of course that a probe is NOT a starship effectively? Aka, it means a more compact system that's arguably easier to service and upgrade.
I will note that I had assumed it was a larger vehicle. However, since we get to see that the starboard "Friendship 1" label is only about the length of a hand (15-20cm), we can compare that against the portside panel shots of the whole probe from the episode and derive a length for the whole thing of 15-20 meters, minus any tail antennae.
The drive from the Expanse is a ridiculous comparison.
Its an alien propulsion system
I'm not talking about the wormhole thing or whatever. I obviously referred to the Epstein drive that is the basis of the show.
Additionally, Friendship One was launched as a proverbial symbol of early Humanity's efforts into deep space and to reach out. Its not impossible to see that SF would want to continue pushing Friendship One that was already out there to preserve that dream.
If their ships can catch up to it, then they can just as well pass it up. It simply doesn't make sense to continue expending time and energy on the old probe at that point. It's more likely they'd have brought it home and displayed it at UFP HQ or a museum.
And again, who said anything about NEW nacelles?
Your argument is that they enhanced the propulsion. That's the powerplant (presumably an antimatter-fueled warp core) and warp nacelles. Seems like bolting on a new drive section would've been the easiest thing out in the middle of space. The next easiest thing would be if it had a swappable core and bolt-on nacelle replacements.
What's more plausible? That the crew of the NX-01 replaced whole nacelles or that they simply modified/change internal circuitry and HW to upgrade it?
The former. When Voyager needed to refurbish her nacelles they landed and dragged the warp coils out of the nacelle housing to work on them. If the Friendship 1 nacelles were five meters long, why not just carry a pair out there and swap them? Seems a lot easier than doing delicate component replacements in open space.
Thank you... but I would like to say that trying to explain the probe getting to about 30,000 LY's with 2067 era tech is eminently FAR more difficult and arguably requires (even within Trek) ridiculous amount of implausibility because it relies on a series of rare, unpredictable and extremely dangerous anomalies lining up so perfectly that would sooner disable, heavily damage or destroy the probe (or at the very least prevent SF from TRACKING it in the first place, therefore losing contact VERY early on)
Nah. I already gave you a less implausible alternative. Friendship 1 gets dropped off at significant distance by a ship capable of reasonably high warp, and they give it a little extra oomph making it a little speedboat, by human standards.
At 100c, it would make another 1000 LY every ten years, which could put her at Planet Self-Destruct by 2347 or so. If we're going to insist on the 2247 date, then we need 160c from our benefactors.
This isn't too bad, especially when you pay attention to the actual warp velocities from the shows rather than the Okuda numbers. Warp five is consistently shown to be around 1500c in Enterprise. It's warp one through warp four that are all the slow speeds, the latter being around 100c.
(Of course, as questionable as the writing of "Friendship One" was insofar as launching a warp driven vehicle with hundreds of years of MTBF rating on its propulsion system, let's be sure not to let Enterprise off the hook. They showed Earth ships hauling 20,000 tonnes of cargo at warp 1.8 on a ship that had been in space for three generations, but suggested that warp two (8c) wasn't surpassed until 2143, with a warp five ship launched a mere eight years later. That is a nutty progression compared to the previously assumed rate of increase, and seems difficult to square with the existence of other Earth Starfleet classes shown.)
The only other good alternative is a wormhole or similar phenomenon within a few hundred light-years of Earth, or preferably a few dozen to account for the fuel running out earlier. The probe encounters this circa 2247 and it stays open long enough for partial telemetry to be sent back, leading to Starfleet having some idea where the vehicle was going to be. Warp drive was obviously offline at the time, preferably from fuel exhaustion in a reasonable timeframe but possibly due to the phenomenon, hence the search radius being a small grid rather than a quadrant.
That's the option I personally prefer as it allows for more reasonable warp speeds and vehicle longevity given the later retcons. The Conestoga, for instance, was launched a couple of years later and capable of about 2c for nine years of sustained flight. This small probe being capable of maybe 4c for maybe 40 years would put it well beyond the reach of Earth at 160 light-years away by 2107, an old harmless relic by the time they could've caught up to it 45 years later.
