I think the point is that he knows while he still has many years of his life ahead of him, eventually he'll be faced with mortality, and when that time comes, h

I think the point is that he knows while he still has many years of his life ahead of him, eventually he'll be faced with mortality, and when that time comes, he would like to have pushed humankind's ability to reach Mars to the point where he could step foot there, live for awhile, and eventually be buried there.