How High Is the Sky?

What IS the sky? Where does it end? Is it really blue? And how high can we fly? This charming flap book appeals to young children's natural sense of curiosity and lets them explore the answers for themselves - from cloud watching to star gazing, peachy sunsets to dazzling Northern Lights, helicopter rides to space travel. Discover the highest thing you can see in the sky, the furthest distance a spacecraft has travelled... and what the sky is really made of.