Monarch butterflies will fly 3,200 kilometres (2,000 miles) from Canada to Mexico for the winter.
Seeing double at night?
Seeing double at night? Looking up at the stars with the naked eye gives
the impression that each star is a single body, like our Sun.
However, in reality at least half of the stars in the sky are made
up of two stars revolving together. These are called
‘binaries’ and they orbit together around a common
centre of mass. 25 JULY 2000
Cool Articles
