Ohr Zarua Latzadik, p.38

For this commandment which I command thee this day, it is not in heaven... [Deuteronomy 30:12]. This refers to the positive commandment of repentance, as it is stated [ibid. 2] and you shall return to the Lord your God with all your heart and with all your soul. And it says that this positive commandment is not in heaven, meaning specifically at the Heavenly Gate in Jerusalem, and not beyond the sea, meaning in all the Land of Israel which is beyond the sea for those living abroad in the land of the sea. Rather, it is close to you, even abroad.

Halichot, vol. 17, Tishrei 5723, p.24

It is clear that even though the Torah was given to those dwelling on our planet and "it is not in the heavens," and the astronaut is floating in the air above the Earth's atmosphere, because the astronaut is inherently connected to life on Earth and lives according to the laws of life on Earth, whether it be in the very cells and instruments of his body, which are taken from earthly materials, or in the food and stored air that he breathes within the spacecraft, which are also from the Earth, and since no person can exist without them - therefore, as long as the soul is within the Jewish person, the commandments of the Torah apply to him in all conditions and places in which he finds himself.

Noam, vol. 13 (5730), p.197

It's clear that this verse, 'It is not in heaven,' doesn't directly address our question here. Because it does not necessarily mean that the Torah does not obligate in heaven. Just as it doesn't intend to say that by stating 'nor is it beyond the sea'. Because in truth, even beyond the sea, the Torah obligates. And if the intention of the verse in writing 'nor is it beyond the sea' is to say that the Torah obligates not only there but also here... then one can attribute this same intention when it says "it is not in heaven".

Noam, vol. 13 (1970), p.199

...If it is necessary to find a source from a verse that commandments that are obligations of the body are obligatory in every place, and this source is derived from the verse "all the days that you live on the earth," then a place that is not on the earth is not obligated, because there is no source for such a place...

...A Jewish person who uproots themself from the earth to the moon, with no intention of returning, would be judged according to their new place and is exempt from the commandments...

...And all the more so this should be the ruling for a Jewish person who is born in this new world...

Ha'odom Al Hayarei'ach, ch. 5

In my humble opinion, it's clear without any doubt that the parameters of Jewish law are that the obligation to observe the commandments of the Torah is a an obligation which applies to the person [as opposed to the subject], and every Jew is obligated to observe the Torah wherever they live, in the heavens above - on the moon - or in the waters beneath the earth, in the north or south poles, where part of the year is all light or all darkness, or in an airplane. As long as they are alive and able to observe the commandments of the Torah, they are obligated to observe them and it is forbidden to transgress any prohibition...

... And it's puzzling how one could introduce such a strange idea, that it's possible for a Jew who was born Jewish to escape and be exempt from all the commandments of the Torah. How did he not ask himself, "the holiness in the person - where did it go?"

Sichos Kodesh - 5752, vol.1, p.160

...when a Jew uses such a machine and flies to the moon, it is obvious that since they are a "divine spark from above", they are not impressed by the wonders of creation, but rather all their awe is of the wonders of the Creator - "How abounding are Your works, O Lord"(Tehillim 104:24) and "How great are Your works, O Lord"(Tehillim 92:6), and the main point is that through this they innovate new ideas and legal rulings in Torah, then they reveal through their work the "dwelling in the lower worlds," that the purpose of all innovations in the world is the addition to the Torah that comes through them.