A hundred kilometres away. (eclipsed all other sources of light). (100)
Six hundred kilometre run across. (600)
Twenty-one hundred hours GMT. (21:00)
One and a half seconds ago. (1.5)
Two hundred years. (200)
More than a generation.
Two and a half second time lag. (2.5)
Five minutes. (5)
After more than three hundred years. (300)
Thirteen magnitudes in twenty-four hours. (13) (24)
Thirteen point four. (13.4)
A quarter of a kilometre away. (1/4) (250)
A billion light years. (1,000,000,000,000)
A hundred thousand times in a few hours. (100,000)
Twenty-four hour system. (24)
Every year a hundred blow up in our galaxy alone. (100)
A hundred times as bright as the sun. (100)