· Uranus
Universe...
Uranus is a planet. It begins with U.
unique..
star
planet Pluto
· Hubble telescope
uniform
udon
unclean :)
You should use a before a word starting with a consanant (not a,e,i,o,u), and use an before a word starting with a vowel(a,e,i,o,u).
unkempt
· unassuming