From this point of view, three verses of the Qur'an should command our full attention. One expresses, without any trace of ambiguity, what man should and will achieve in this field. In the other two, God refers for the sake of the unbelievers in Makka to the surprise they would have if they were able to raise themselves up to the Heavens; He alludes to a hypothesis which will not be realized for the latter.

1) The first of these verses is sura 55, verse 33: "O assembly of Jinns and Men, if you can penetrate regions of the heavens and the earth, then penetrate them! You will not penetrate them save with a Power."

The translation given here needs some explanatory comment:
a) The word 'if' expresses in English a condition that is dependent upon a possibility and either an achievable or an unachievable hypothesis. Arabic is a language which is able to introduce a nuance into the condition which is much more explicit. There is one word to express the possibility (ida), another for the achievable hypothesis (in) and a third for the unachievable hypothesis expressed by the word (lau). The verse in question has it as an achievable hypothesis expressed by the word (in). The Qur'an therefore suggests the material possibility of a concrete realization. This subtle linguistic distinction formally rules out the purely mystic interpretation that some people have (quite wrongly) put on this verse.

b) God is addressing the spirits (jinn) and human beings (ins), and not essentially allegorical figures.

c) 'To penetrate' is the translation of the verb nafada followed by the preposition min. According to Kazimirski's dictionary, the phrase means 'to pass right through and come out on the other side of a body' (e.g. an arrow that comes out on the other side). It therefore suggests a deep penetration and emergence at the other end into the regions in question.

d) The Power (sultan) these men will have to achieve this enterprise would seem to come from the All-Mighty.'
There can be no doubt that this verse indicates the possibility men will one day achieve what we today call (perhaps rather improperly) 'the conquest of space'. One must note that the text of the Qur'an predicts not only penetration through the regions of the Heavens, but also the Earth, i.e. the exploration of its depths.
2) The other two verses are taken from sura 15, (verses 14 and 15). God is speaking of the unbelievers in Makka, as the context of this passage in the sura shows:
"Even if We opened unto them a gate to Heaven and they were to continue ascending therein, they would say: our sight is confused as in drunkenness. Nay, we are people bewitched."
The above expresses astonishment at a remarkable spectacle, different from anything man could imagine.
The conditional sentence is introduced here by the word lau which expresses a hypothesis that could never be realized as far as it concerned the people mentioned in these verses.
When talking of the conquest of space therefore, we have two passages in the text of the Qur'an: one of them refers to what will one day become a reality thanks to the powers of intelligence and ingenuity God will give to man, and the other describes an event that the unbelievers in Makka will never witness, hence its character of a condition never to be realized. The event will however be seen by others, as intimated in the first verse quoted above. It describes the human reactions to the unexpected spectacle that travelers in space will see: their confused sight, as in drunkenness, the feeling of being bewitched...
This is exactly how astronauts have experienced this remarkable adventure since the first human space flight around the world in 1961. It is known in actual fact how once one is above the Earth's atmosphere, the Heavens no longer have the azure appearance we see from Earth, which results from phenomena of absorption of the Sun's light into the layers of the atmosphere. The human observer in space above the Earth's atmosphere sees a black sky and the Earth seems to be surrounded by a halo of bluish color due to the same phenomena of absorption of light by the Earth's atmosphere. The Moon has no atmosphere, however, and therefore appears in its true colors against the black background of the sky. It is a completely new spectacle therefore that presents itself to men in space, and the photographs of this spectacle are well known to present-day man.
Here again, it is difficult not to be impressed, when comparing the text of the Qur'an to the data of modern science, by statements that simply cannot be ascribed to the thought of a man who lived more than fourteen centuries ago.