Greetings all,
On Tuesday, March 9, 2021 at 12:14:43 AM UTC+2, Alain Fournier wrote:
much snipped

For a stronger definition of a colony, such as a group living on Mars
and capable of growing and surviving indefinitely without receiving
supplies from Earth, yes I would say that will take more than 20 years.


Even with the great strides made by SpaceX I'm still somewhat cynical of the 20-ish year deadline for Humans on Mars. Let's just put it down to me having been disappointed by lack of progress in the past (NASA and Washington, I'm talking about you, and Apollo and Skylab, and the X-33 and the whole damn Shuttle program).

I'm forgetting who did it but one of the historical colony leaders got where they were going, unloaded and then torched the ships (i'm not thinking of William I, it might be Cortez, or one of his contemporaries. Not necessarily smart, but it gives people a definite message: You are not going home the same way you came.

The equivalent on Mars would sending your Mars Habitat to Mars and instead of sending your Mars Ascent vehicle (or Mars Return Vehicle) sending another Mars Hab packed with supplies. No MAV/MRV no way home for another 18 months (it is 18 months). Better get that hydroponic greenhouse deployed, and find the best water containing regolith to mine.


Alain Fournier

Regards
Frank