voyagers in space
lis+read+quiz??1
Signals take about seventeen hours to arrive.by that time ,they’ve faded to about 0.2 billion-billion (.0000000000000002) of a watt.voyagers in space
lis+read+quiz??1
Signals take about seventeen hours to arrive.by that time ,they’ve faded to about 0.2 billion-billion (.0000000000000002) of a watt.