Personally, I think that a distinction should be made between "spirituality" and belief if God. I haven't read the book you are referring to...never even heard of it, but it seems that is what he is saying from those two quotes. I'll have to pick up a copy. Sounds like interesting reading.
For myself, I don't really get an impression of "deity" when I look at the stars, but I do feel it sometimes. Like when I am outside, and I take my shoes off, I can feel "something" from the earth. Not dirt in between my toes so much, but a sense of connected-ness-- like energy or vibration. Also, when I am in a stand of trees, I feel a need to put my hands on the trees. It's almost like I want to touch their long lives. For me, that IS spirituality, even if I look pretty silly doing it. It's very centering.
Odrade