Not to me they don't.
In the first 'space' the area between planets, stars, etc. and the oxygen is released from a point within that area. That is not from a point outside it.
In the second, on the other hand, 'space' is some empty area the speaker has been conversing about with the listener (for example the space between the inner and outer parts of a thermos flask) and in this case the oxygen enters the space in question from the outside.
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