The Ascension is one of the Great Feasts that we tend to ignore.
When I was studying theology in the 1960's the fashionable theologians were Tillich, Bultmann & Bonhoeffer and there was a tremendous emphasis on exegesis and demythologising. It was the Jesus Seminar in the States in the 1990's that took this approach to ultimate lengths and considered the Ascension to be a post-apostolic fabrication to bring to an end "appearances" of the Lord to individuals and groups.
I used to find a great deal of intellectual entertainment in testing many of these theories and following the arguments of the Jesus Seminar but, like St Thomas Aquinas, I've realised that it doesn't help me very much in my own personal spiritual struggle. In many ways it is a red herring that draws me away from focussing on what Christianity is all about.
And the Ascension? I've moved on from that impression of Jesus being taken up to Heaven in some sort of cosmic lift to 70 floors above haberdashery, ladies underwear and the Roof Garden Tea Room. It seems to me that the movement is towards mankind, rather than away from it. Somehow the Apostles saw Jesus enter into the Glory of His Majesty, prefigured at the Transfiguration, with the promise that they, and we too, would be able to share in it in the future. In the meantime the Spirit would come to help us make that possible. The Ascension, then, is the culmination of the Incarnation. God became man and, at the Ascension, Christ's manhood is taken up to God.
The Ascension also underlines that unique claim of Christianity, that created things are ultimately good and that body and soul are indefinably connected. Jesus is taken up into Heaven materially. How, we don't know, and Luke does his best to describe it in Acts but he is limited by his own time. What actually happened doesn't matter but Heaven touched Earth at a moment in time.