Jonathan_S wrote:As you say it depends on star and planet involved, but I thought I'd do some quick number crunching on our star system of Manticore.Fireflair wrote:What's the transit time from the hyper limit to the planet? Depends on the star and the planet involved, but it's not minutes. It's hours. Mycroft controlled missiles could be in motion as soon as you're sure of the threat, from outside the detectable range of the attackers. More over missiles accelerate to their max velocity pretty quickly, so their time to cross the distance is much shorter than the star ships you're mobilizing.
Manticore orbits its star at 11.5 lm
Sphinx orbits at 21.2 LM
Hyper Limit is 22.0 LM
This is a fast as possible approach, so drop down to the Alpha bands, work up the the full 0.6c to carry as much velocity as possible over the hyper limit, and a zero safety margin emergency right on the hyper limit. I'll assume a fleet acceleration of 500 gees (which is way quicker than SLN SDs though way slower than RMN ones). Oh and we'll go for a high-speed flyby, not a zero-zero intercept.
In the alpha bands 0.6c (179875 km/s), drop to n-space and suffer the 92% velocity drop. Base velocity 14,390 km/s.
Sphinx is 0.8 lm (143,900,000 km) away
Manticore is 10.5 lm (1,888,700,000 km) away
From the base velocity, at 500 gees, it will take:
87 minutes 50 seconds to reach Sphinx
416 minutes 23 seconds (about 6.9 hours) to reach Manticore
Now if you were just interested in getting within 45,000,000 km to have a pretty solid MDM shot at orbital infrastructure Sphinx would be "only" 67 minutes 42 seconds away.
Jonathan, your math is off by an order of magnitude, .8 lm is only 14.3 Mkm. 10.5 lm is only just over 1AU, at 188 Mkm.