Let us imagine a journey to a star 10 light years away. We start from Mars orbit and outside the planet’s gravitational pull and use advanced rocket technology to reach Jupiter. This is a journey of 555 million kilometres [km] taking 7-8 months at 100,000 km per hour. [Approx. estimate of future capability]
We use the immense mass of Jupiter to attract and accelerate our craft onto a collision course [initially] and at the critical moment re-fire the advanced rockets to sling our spaceship around the gas giant and onto its new trajectory and new speed of 1 million km/hour.
Now we start the nuclear reactor, the only power plant capable of sustaining thrust over a 20 year journey [unless we discover something remarkable during the next 100 years]. The heat output from this reactor would be used to power a new type of drive capable of pushing our craft towards light speed. I will describe one concept which has been around for decades, surprisingly – the ion drive.
Here a stream of positively charged hydrogen ions [H+] is ejected at high speed from the rear of the object being propelled. The thrust is small but in the vacuum of space even a large object can be manoeuvred and accelerated provided you have enough thrusters. The ion drive of a starship is likely to be 50-80 metres in diameter and each of the thrusters say 5 cm round. You could get over 2 million thrusters in this drive [clustered around the advanced rockets] all contributing their power from the emitting stream of hydrogen ions.
By providing constant sufficient acceleration you would design to accelerate from 0.001c to 0.5c in 1 year [c = speed of light].
Thus our journey to a star 10 light years away would be approximately 23 years – 2 years to accelerate, 20 to get there and 1 year to slow down to a manageable speed to orbit around a target planet of our destination star.
I’m sure the mathematicians among you can calculate the acceleration required and the typical thrust needed from each tube – can we achieve this in 150 years time?
I think we can and in 2150 my starship leaves Mars for the star Seren, 10 light years away, in search of – The Blue People of Cloud Planet.