Answer:
You can see it everyday, but cannot touch it at will. What is it?
What is an astronautโs favorite key on a keyboard?
I am a rock group with four members. All dead one was assassinated.
I am perfect with a head perfect without a head; Perfect with a tail perfect without a tail; Perfect with either neither or both.
Lighter than feather and softer than silk, yet the strongest man in the world cannot hold me for more than a few minutes. What am I?
No matter how little or how much you use me, you change me every month.