Your question talks about an unknown future based on assumptions.
I would start with referring to the below Hadith:
It was narrated that Abu Hurairah said: "The Messenger of Allah (ﷺ)
said: 'The strong believer is better and more beloved to Allah than
the weak believer, although both are good. Strive for that which will
benefit you, seek the help of Allah, and do not feel helpless. If
anything befalls you, do not say, "if only I had done such and such"
rather say "Qaddara Allahu wa ma sha'a fa'ala (Allah has decreed and
whatever he wills, He does)." For (saying) 'If' opens (the door) to
the deeds of Satan.'"
Sunan Ibn Majah Vol. 1, Book 1, Hadith 79
In Islamic scriptures, there is no mention of human settlements on another celestial body, not even the moon. Many modern day scholars believe that one of the things to note among the signs of end times that Allah has given us is the fact that all of them occur on earth. We know that the Final Hour will come on everything that is alive. So all creatures including humans, jinns, animals, birds, plants, microbes and those that we are not aware of will die. Hence, it is highly unlikely that humans will settle on another planetary body.
كُلُّ نَفْسٍ ذَآئِقَةُ الْمَوْتِ
Every soul shall taste Death
The earth was described by the Prophet (SAW) as an old woman and in another Hadith he said that he and the final hour are very close.
Narrated Sahl bin Sad As-Saidi:
(a companion of Allah's Messenger (ﷺ)) Allah's Messenger (ﷺ), holding
out his middle and index fingers, said, "My advent and the Hour's are
like this (or like these)," namely, the period between his era and the
Hour is like the distance between those two fingers, i.e., very short.
Sahih al-Bukhari, Vol. 7, Book 63, Hadith 221
In short, our time below this universe of the first sky is very short. We should avoid assuming things and coming up with laws for events that are still ghaib. It is more beneficial for us to concentrate on our present life, educate our parents, siblings, children, friends on Islam and help the next generation to be on the straight path. Inshallah this will be sawab-e-jariya.
Based on the conversation with @Monty Wild in the comment section, I am adding the below ayah from the Quran 2:172 and 2:173:
O you who have believed, eat from the good things which We have provided for you and be grateful to Allah if it is [indeed] Him that you worship. He has only forbidden to you dead animals, blood, the flesh of swine,
and that which has been dedicated to other than Allah . But whoever is
forced [by necessity], neither desiring [it] nor transgressing [its
limit], there is no sin upon him. Indeed, Allah is Forgiving and
As the ayah shows in exceptional cases, the live of a person takes precedence over the laws of Halal and Haram. (More details in the comment section)