If you do the math, going at the speed of the Pluto probe, 54,726 years
Yes, that’s what I came up with for a spacecraft moving at 50,000 mph. It would take over 54,000 years to reach the nearest star, Promixa Centauri, which is about 25 trillion miles away. The size of the universe is mind boggling.
Probably divide that by 20 or so in the next 20 years, not good, but not quite as bad.
Which is only about 5 times the length of human civilization from its beginning in the fertile crescent.
Our solar system probes are all “coasters.” Meaning the spacecraft accelerates via chemical rocket engine to a given speed of, say, 20-30,000 mph then they coast at that speed to the destination.
Absent some warp drive (Hollywood hooey) or a worm hole type of short cut, figure on a constant acceleration to the far off place in the 1G range via nuclear-powered engine or nuke plus light sail, perhaps. Acceleration at 1G allows travelers to live in more or less “normal” gravity or so it would seem.
At such a constant acceleration, calculations say you would travel approx .5 light year in the the first year of travel and a little more that one year of time for each additional light year distance. The craft could never reach the speed of light but would approach it nicely.
Of course, the craft will need to slow back down so at the half-way point it must flip 180 degrees and begin to deccelerate, still at that same 1G of thrust.
Present technology doesn’t allow for constant thrust at 1G for years but it seems like it should be an attainable goal. Such a craft would cut the travel time from 10s of thousands of years to a trip that can be done in a human lifetime.