Here’s a thought…
When is the ‘best’ time to fly through space? Given the technology is always advancing, the velocity of space vehicles will tend to increase over time. So, how does this affect journey times in space?
Here’s a scenario:
Imagine it is the year 2000 and a spacecraft can travel at maximum velocity, v. It leaves the Earth for a planet which will take 40 years to reach. So, it will arrive in the year 2040.
Now imagine that by the year 2010 the technology has improved such that the new spacecrafts can travel at twice the velocity of the first craft, i.e. 2v. It leaves for the same planet in 2010 and arrives there 20 years later (twice the speed!!) in the year 2030 – that’s 10 years before the first spacecraft!!
In the year 2020 the new spacecrafts can fly twice as fast as those in 2010 – i.e. 4v. It leaves the Earth for the same planet and arrives in 2030, having only taken 10 years to reach there (twice as fast as spacecraft 2).
So, the spacecraft which left the Earth in 2010 and 2020 both arrive at the same time!
Then, in 2030 the velocity has doubled again to 8v. It leaves Earth and arrives in 5 years, 2035 – five years before the first spacecraft which will not arrive until 2040!
The above scenario assumes that the maximum velocity of spacecraft will double every ten years. Yet, even this ‘modest’ increase in speed results in very interesting outcomes for the occupants of each craft.
It begs the question, why should the first spacecraft go at all?
But, if the first craft doesn’t go, then the second craft becomes the ‘first’ craft and is in exactly the same situation as the original ‘first’ craft!
Naturally, I’m assuming that all of these spacecrafts travel at well below light-speed, otherwise time dilation effects kick in – which is not good….