Space exploration is the discovery and exploration of outer space by means of space technology. Physical exploration of space is conducted both by human spaceflights and by robotic spacecraft.
- Houston, Tranquility Base here. The Eagle has landed.
- First words from the Apollo 11 lunar module Eagle after guiding the craft to a landing on the moon at 4:17pm EDT (20 July 1969); reported in The Washington Post (July 21, 1969), p. 1.
- That's one small step for (a) man, one giant leap for mankind.
- Words said when Armstrong first stepped onto the moon (20 July 1969); reported in The Washington Post (July 21, 1969), p. 1. In the actual sound recordings he apparently fails to say "a" before "man" and says: "That's one small step for man, one giant leap for mankind." This was generally considered by many to simply be an error of omission on his part. Armstrong long insisted he did say "a man" but that it was inaudible. Prior to new evidence supporting his claim, he stated a preference for the "a" to appear in parentheses when the quote is written. In September 2006 evidence based on new analysis of the recordings conducted by Peter Shann Ford, a computer programmer based in Sydney, Australia, whose company Control Bionics helps physically handicapped people to use their own nerve impulses to communicate through computers, indicated that Armstrong had said the missing "a." This information was presented to Armstrong and NASA on 28 September 2006 and reported in the Houston Chronicle (30 September 2006). The debate continues on the matter, as "Armstrong's 'poetic' slip on Moon" at BBC News (3 June 2009) reports that more recent analysis by linguist John Olsson and author Chris Riley with higher quality recordings indicates that he did not say "a".
- We will build new ships to carry man forward into the universe, to gain a new foothold on the moon, and to prepare for new journeys to worlds beyond our own.
- Returning to the moon is an important step for our space program. Establishing an extended human presence on the moon could vastly reduce the costs of further space exploration, making possible ever more ambitious missions. Lifting heavy spacecraft and fuel out of the Earth's gravity is expensive. Spacecraft assembled and provisioned on the moon could escape its far lower gravity using far less energy, and thus, far less cost. Also, the moon is home to abundant resources. Its soil contains raw materials that might be harvested and processed into rocket fuel or breathable air. We can use our time on the moon to develop and test new approaches and technologies and systems that will allow us to function in other, more challenging environments. The moon is a logical step toward further progress and achievement.
- The emergence of this new world poses a vital issue: will outer space be preserved for peaceful use and developed for the benefit of all mankind? Or will it become another focus for the arms race—and thus an area of dangerous and sterile competition? The choice is urgent. And it is ours to make. The nations of the world have recently united in declaring the continent of Antarctica "off limits" to military preparations. We could extend this principle to an even more important sphere. National vested interests have not yet been developed in space or in celestial bodies. Barriers to agreement are now lower than they will ever be again.
- Dwight D. Eisenhower, address before the fifteenth General Assembly of the United Nations, New York City, September 22, 1960. Public Papers of the Presidents of the United States: Dwight D. Eisenhower, 1960–61, p. 714.
- First, I believe that this nation should commit itself to achieving the goal, before this decade is out, of landing a man on the moon and returning him safely to the earth…. I believe we should go to the moon. But … there is no sense in agreeing or desiring that the United States take an affirmative position in outer space, unless we are prepared to do the work and bear the burdens to make it successful.
- John F. Kennedy, special message to a joint session of Congress on urgent national needs, May 25, 1961. The Public Papers of the Presidents of the United States: John F. Kennedy, 1961, p. 404, 405.
- Many years ago the great British explorer George Mallory, who was to die on Mount Everest, was asked why did he want to climb it. He said "Because it is there." Well, space is there, and we're going to climb it, and the moon and the planets are there, and new hopes for knowledge and peace are there.
- John F. Kennedy, address on the nation's space effort, Rice University, Houston, Texas, September 12, 1962. Public Papers of the Presidents of the United States: John F. Kennedy, 1962, p. 668. Mallory's remark, "Because it's there," was reported in The New York Times, March 18, 1923, p. 11, during his visit to New York.
- To see the earth as we now see it, small and blue and beautiful in that eternal silence where it floats, is to see ourselves as riders on the earth together, brothers on that bright loveliness in the unending night—brothers who see now they are truly brothers.
- Archibald MacLeish, "Bubble of Blue Air," Riders on the Earth; Essays and Recollections by Archibald MacLeish, epigraph, p. xiv (1978). This was written by MacLeish for The New York Times "after the Apollo mission of 1968 returned from space with a photograph of what earth looked like as seen from beyond the moon: the photograph which gave mankind its first understanding of its actual situation; riders on the earth together, brothers on that bright loveliness in the unending night—brothers who see now they are truly brothers (p. ix). The article has slightly different wording and reads as follows: "To see the earth as it truly is, small and blue and beautiful in that eternal silence where it floats, is to see ourselves as riders on the earth together, brothers on that bright loveliness in the eternal cold—brothers who know now they are truly brothers". The New York Times (December 25, 1968), p. 1.
- Some say God is living there [in space]. I was looking around very attentively, but I did not see anyone there. I did not detect either angels or gods…. I don't believe in God. I believe in man—his strength, his possibilities, his reason.
- Gherman Titov, Soviet cosmonaut, comments at world's fair, Seattle, Washington (May 6, 1962), as reported by The Seattle Daily Times (May 7, 1962), p. 2.
- Yet I do seriously and on good grounds affirm it possible to make a flying chariot in which a man may sit and give such a motion unto it as shall convey him through the air. And this perhaps might be made large enough to carry divers men at the same time, together with food for their viaticum and commodities for traffic. It is not the bigness of anything in this kind that can hinder its motion, if the motive faculty be answerable thereunto. We see a great ship swims as well as a small cork, and an eagle flies in the air as well as a little gnat…. 'Tis likely enough that there may be means invented of journeying to the moon; and how happy they shall be that are first successful in this attempt.
- John Wilkins, A Discourse Concerning a New World and Another Planet (1640), book 1, chapter 14, p. 238–39 (spelling modernized).