Thanks Jen revamping this thread, as I thought of a few other song since you first posted this... So how about;
"Just Be" by DJ Tiësto (2004)
Although it is not really about inner space and not outer space, I've just always loved the "observational" lyrics;
"You can travel the world but you can't run away
From the person you are in your heart
You can be who you want to be
Make us believe in you
Keep all your light in the dark
If your searching for truth
You must look in the mirror
and make sense of what you can see
Just be. Just be."
Also many of the Dutch Tiësto trance and electronic dance music is often about flight and escaping. Vocalist is Kirsty Hawkshaw.
(There is also a nice space related video on YouTube, about Apollo 11 to this song at;
http://www.youtube.com/watch?v=i6D2T...eature=related )
A shorter 5:29 version is at
http://www.youtube.com/watch?v=EzrxopKkpr8 (but is not really space vid related)
Nice when observing too...
Another great Tiësto song that reminds me of astronomy and escaping is "Walking on Clouds" - not because is about space but walking on clouds on cloudy nights. A nice vid and quality version of the track is at ;
http://www.youtube.com/watch?v=-gG2ifeI3RM