The Slowness of Light
Light travels at only about 670 million miles per hour. The Kuiper Belt object, nicknamed Ultima Thule, that is about to be photographed in high resolution by the New Horizons spacecraft as it flies past on New Years, is nearly 10 times that distance--about 6.5 billion miles from earth. So the (light speed, radio) signals transmitted from New Horizons back to Earth will take a almost 10 hours to get here.
When you think of the size of our tiny solar system--of which Ultima Thule is a member, compared to the staggering size of our home galaxy, the Milky Way, and the ineffable "size" of the universe, the speed of light seems like a real slow poke.
Shine a really expensive flashlight at Ultima Thule, and the light takes 10 hours to get there--at the speed of light! That's long enough to sit back on your front porch for a long summer day, with a large pitcher or two of iced tea and a handful of large cigars, and smoke every one of them, in the time for a light beam to make it to Ultima Thule.
Bob
Light travels at only about 670 million miles per hour. The Kuiper Belt object, nicknamed Ultima Thule, that is about to be photographed in high resolution by the New Horizons spacecraft as it flies past on New Years, is nearly 10 times that distance--about 6.5 billion miles from earth. So the (light speed, radio) signals transmitted from New Horizons back to Earth will take a almost 10 hours to get here.
When you think of the size of our tiny solar system--of which Ultima Thule is a member, compared to the staggering size of our home galaxy, the Milky Way, and the ineffable "size" of the universe, the speed of light seems like a real slow poke.
Shine a really expensive flashlight at Ultima Thule, and the light takes 10 hours to get there--at the speed of light! That's long enough to sit back on your front porch for a long summer day, with a large pitcher or two of iced tea and a handful of large cigars, and smoke every one of them, in the time for a light beam to make it to Ultima Thule.
Bob