Please project on a white or otherwise bright ceiling or wall and use in a dark room.Please use the included AC adapter. The starry sky will revolve around your room in about 12 minutes. You may need to adjust the projection angle and focus point. The manual is in Japanese,but it"s very easy to enjoy it. The warranty lasts for 6 months after purchase.This product　is recommended in astronomical learning of children,and comfortable sleep for adult.Iｔ was introduced famous newspaper of Japan in "The Nikkei". (August 9 2013)