I thought you might also be interested in this, a subway style map of transit
requirements from earth to other worlds in the solar system.

http://i.imgur.com/AAGJvD1.png

	One of the challenges I've seen out of this thread is taking detailed
information (like delta-V requirements) and presenting it in a clear manner for
viewers that may not be as interested in all of the details. But this is a neat
approach.

On 1/29/2018 3:35 AM, Caleuche wrote:
> Mucking around with the atmospheric drag model (which now models the changing Cd of that particular shape in transsonic flight - very little overall change as the majority of atmospheric flight is hypersonic), I modeled a nearly energy-free orbit circularization which ended in a landing (though the ship could have remained in orbit by a fairly low delta-v change at apogee on the last orbit). Nearly all Traveller school children know this, but it was interesting to see it anyway, acceleration applied exactly toward or against the direction of travel at perigee results in a lowering of apogee, but not perigee.
>
> The Hamiltonian in a skimming orbit: https://i.imgur.com/oXtCQj1.gifv(video advances at a rate of about 1h24m per second if your browser plays back at 24 fps)
>
> The heat flux is high enough during the last 1/3 orbit from about 99700 seconds to landing at 101292 seconds that some meteor trail will be visible and by 100900 seconds, descending below 60 km, the visible effect would be quite bright to someone watching from the ground.
>
> This does mimic the Chelyabinsk meteorite fairly well: http://cams.seti.org/Popova2013-ms.pdf
>
> I thought one possible game element would be one constrained by time, a ship left in an eccentric orbit decaying over a period of a bit more than a day undergoing skimming through the very upper atmosphere periodically, with those skims becoming more frequent over time. I didn't realize before this weekend just how narrow the useful window of atmospheric skimming is, and it's pretty unlikely that a ship would randomly be left in a skimming trajectory. As repeatedly pointed out, of course, in the Traveller world above about TL9 there is really no reason for a crewed ship to ever do these kind of upper atmosphere-orbital maneuvers, but the model is probably useful to keep around for the typical unintentional side effects of near-planetary-space battle.-----
> The Traveller Mailing List
> Archives at http://archives.simplelists.com/tml
> Report problems to xxxxxx@simplelists.com
> To unsubscribe from this list please go to
> http://www.simplelists.com/confirm.php?u=QWmJ5KKpHa3MBU63jjs3knG6o9jLMkSu
>

--
         Thomas Jones-Low
Work:	xxxxxx@softstart.com
Home:   xxxxxx@gmail.com